| Sysop: | Amessyroom |
|---|---|
| Location: | Fayetteville, NC |
| Users: | 40 |
| Nodes: | 6 (0 / 6) |
| Uptime: | 12:43:58 |
| Calls: | 291 |
| Files: | 910 |
| Messages: | 76,473 |
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably
require a native French speaker to decypher, but who knows? :-)
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are
a set in French. I can't use Google translate because they've used too >>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are >>>> a set in French. I can't use Google translate because they've used too >>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort >>> out some technical instructions in French If you want to send them to >>> me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some
of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are >> >>>> a set in French. I can't use Google translate because they've used too >> >>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort >> >>> out some technical instructions in French If you want to send them to >> >>> me, I'll have a go (you should be able to work out my e-mail address). >> >>
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some
of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >819-line high-definition television service which had been translated
from French by someone who knew nothing about television or radio >terminologyy. It was hilarious nonsense but I eventually managed to >translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably
Do we have any French speakers on the Panel? I have a radio that's >>>>>>> badly in need of realignment and the only instructions I can find are >>>>>>> a set in French. I can't use Google translate because they've used too >>>>>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort >>>>>> out some technical instructions in French If you want to send them to >>>>>> me, I'll have a go (you should be able to work out my e-mail address). >>>>>
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some
of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French
819-line high-definition television service which had been translated
from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably >>>>>> require a native French speaker to decypher, but who knows? :-)
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>> badly in need of realignment and the only instructions I can find are >>>>>>>> a set in French. I can't use Google translate because they've used too >>>>>>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort >>>>>>> out some technical instructions in French If you want to send them to >>>>>>> me, I'll have a go (you should be able to work out my e-mail address). >>>>>>
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some >>>> of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French
819-line high-definition television service which had been translated >>>from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
Cursitor Doom <cd@notformail.com> wrote:
[...]
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
Here's my version. I couldn't display the tables as tables, so I have >repeated the headers as individual paragraphs. One or two bits didn't
make sense, so I have indicated them with question marks. See the >originalpublication for the diode probe circuit.
Beware, the text is scattered with roman numerals.
INSTRUCTIONS FOR ADJUSTMENT
Agjustment on 9v D.C.,
Adjustment of the final audio Push-Pull stage.
Insert a milliameter in place of the link at the Collector of AC 188 K
(use point -x-). Adjust the quiescent current to 6.5mA by means of R410
(500 0hms). After adjusting the current, resolder the link.
Adjustment of the IF amplifier:
By means of R515, adjust the Collector current of T IV to obtain a
voltage drop of 1.35V across the Emitter resistorR518
-----------------------------
Adjustments FM intermediate frequency 10.7 Mhz Switched to "FM".
Adjustment: F VII
Couple wobbulator output to: MP5
Measuring equipment: Diode probe [as circuit] to F VII point 6
Adjust for: (a) Off tune. ( b) At maximum and symmetrical
Adjustment: F VI & F V
Couple wobbulator output to: MP3
Measuring equipment: Diode probe [as circuit] to F VII point 6
Adjust for: (c) & (d) maximum and symmetrical
Adjustment: F IV & F III
Couple wobbulator output to: MP2
Measuring equipment: Diode probe [as circuit] to F VII point 6
Adjust for: (e) & (f) maximum and symmetrical
Adjustment: FII & FI
Couple wobbulator output to: ?close? to mixer
Measuring equipment: Diode probe [as circuit] to F VII point 6
Adjust for: (g) & (h) maximum and symmetrical
Adjustment: Discriminator
Couple wobbulator output to: MP5
Measuring equipment: Across 50 kilohm cable on MP11 (at audio input)
Adjust for: symetricality. During this sdjustment the signal must be
very weak so that FI doesn't limit.
-----------------------------
Adjustments AM intermediate frequency 460 Khz Switched to Medium Wave >["PO".]
Adjustment: F XIII & F XII
Couple wobbulator output to: MP3 F III
Measuring equipment: Test point ?? MP4
Adjust for: (I) & (II) maximum and symmetrical
Adjustment: FXI
Couple wobbulator output to: MP8
Measuring equipment: Test point ?? MP4
Adjust for: (III) maximum and symmetrical
Adjustment: F X & F IX
Couple wobbulator output to: CV AM, MP7
Measuring equipment: Test point ?? MP4
Adjust for: (IV) & (V) maximum and symmetrical
--------------------------
Adjustment of the AM oscillator and input stage.
When aligning Long Wave and Medium Wave, couple to the ferrite rod
aeraial across the frame [????]. Short Wave alignmnet is done with the >telescopic aerial unsoldered. The signal is injected by a 15pf
capacitor into the telescopic aerial terminal.
Medium Wave
Tuning dial set to 560 Khz
Adjust oscillator for (1) maximum
Adjust input circuit for (3) max
Mixer sensitivity 13uV
Oscillator output 60 - 90 mV
Medium Wave
Tuning dial set to 1450 Khz
Adjust oscillator for (2) maximum
Adjust input circuit for (4) max
Mixer sensitivity 14uV
Oscillator output 60 - 90 mV
Long Wave
Tuning dial set to 160 Khz
Adjust oscillator for ---
Adjust input circuit for (6) max
Mixer sensitivity 13uV
Oscillator output 65 - 95 mV
Long Wave
Tuning dial set to 240 Khz
Adjust oscillator for (5) maximum
Adjust input circuit for (7) max
Mixer sensitivity 10 uV
Oscillator output 65 - 95 mV
Short Wave
Tuning dial set to 6.6 Mhz
Adjust oscillator for (8) maximum
Adjust input circuit for (10) max
Mixer sensitivity 5 uV
Oscillator output 35 - 90 mV
Short Wave
Tuning dial set to 15 Mhz
Adjust oscillator for (9) maximum
Adjust input circuit for (11) max
Mixer sensitivity 4.5 uV
Oscillator output 35 - 90 mV
---------------------
Oscillator and IF alignment
Tuning dial set to 88 Mhz
Adjust oscillator for (A) maximum
Adjust IF coil for (C) max
Hiss level around 5 kT0 ... [No idea what that means]
Oscillator voltage on Emitter of T II 75 - 85 mV
Tuning dial set to 106 Mhz
Adjust oscillator for (B) maximum
Adjust IF coil for (D) max
Hiss level around 5 kT0 ... [No idea what that means]
Oscillator voltage on Emitter of T II 75 - 85 mV
Notes:
Inject the signal from an oscillator with an internal impedance of 60
ohms directly into the mixer. After alignment, coupled by 60 ohms, the >fundamental of the oscillator into the input of the mixer must be less
than 2 mV.
On 12/21/24 22:07, Cursitor Doom wrote:
On Sat, 21 Dec 2024 21:31:51 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>>>> (Liz Tuddenham) wrote:I'm not a native French speaker, but I may be able to help anyway. >>>>>>> Fire away.
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>>>> badly in need of realignment and the only instructions I can find areI'm not a particularly fluent French speaker, but I could probably sort
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense. >>>>>>>>>
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably >>>>>>>> require a native French speaker to decypher, but who knows? :-) >>>>>>>
Well that's interesing as I had did think you might respond given some >>>>>> of the background you've revealed here in the past. I don't have the >>>>>> relevant page here right now, but will make it available tomorrow. It >>>>>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks >>>>>> ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can >>>>>> speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >>>>> 819-line high-definition television service which had been translated >>>> >from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to >>>>> translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
Thanks, Jeroen. Geez, you just can't win with these bastards. I've got
a 50 ohm signal generator and a 70 ohm one - but that's not good
enough for 'em. No, they want me to splash out on a 60 ohm one and
where am I going to source one of those??
And it doesn't stop there! I thought all my vintage servicing voltage
reading requirements would be met when I bought an old analogue Avo
with 20kohms/volt. But now it seems I need to scratch around for a
500ohms/volt one. It seems they're expecting whoever services these
things to have access to an infinite range of test equipment to
satisfy whatever whim the manual compiler for the equipment had at the
time. <making overly theatrical gesture of despair>
I don't think that matters all that much, really. Your VNA will
do fine as a signal source and a scope will do fine to measure
resulting signals and voltages. If really necessary, put ten ohms
in series with your 50 Ohm source.
On Sat, 21 Dec 2024 21:31:51 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably >>>>>>> require a native French speaker to decypher, but who knows? :-)
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>>> badly in need of realignment and the only instructions I can find are >>>>>>>>> a set in French. I can't use Google translate because they've used tooI'm not a particularly fluent French speaker, but I could probably sort
many abbreviations in the text and they won't parse any sense. >>>>>>>>
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address). >>>>>>>
I'm not a native French speaker, but I may be able to help anyway. >>>>>> Fire away.
Well that's interesing as I had did think you might respond given some >>>>> of the background you've revealed here in the past. I don't have the >>>>> relevant page here right now, but will make it available tomorrow. It >>>>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >>>> 819-line high-definition television service which had been translated
from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
Thanks, Jeroen. Geez, you just can't win with these bastards. I've got
a 50 ohm signal generator and a 70 ohm one - but that's not good
enough for 'em. No, they want me to splash out on a 60 ohm one and
where am I going to source one of those??
And it doesn't stop there! I thought all my vintage servicing voltage
reading requirements would be met when I bought an old analogue Avo
with 20kohms/volt. But now it seems I need to scratch around for a 500ohms/volt one. It seems they're expecting whoever services these
things to have access to an infinite range of test equipment to
satisfy whatever whim the manual compiler for the equipment had at the
time. <making overly theatrical gesture of despair>
On Sat, 21 Dec 2024 21:31:51 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
Thanks, Jeroen. Geez, you just can't win with these bastards. I've got
a 50 ohm signal generator and a 70 ohm one - but that's not good
enough for 'em. No, they want me to splash out on a 60 ohm one and
where am I going to source one of those??
And it doesn't stop there! I thought all my vintage servicing voltage
reading requirements would be met when I bought an old analogue Avo
with 20kohms/volt. But now it seems I need to scratch around for a 500ohms/volt one.
It seems they're expecting whoever services these
things to have access to an infinite range of test equipment to
satisfy whatever whim the manual compiler for the equipment had at the
time. <making overly theatrical gesture of despair>
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10
ohms....
On Sat, 21 Dec 2024 21:37:59 +0000, Cursitor Doom wrote:
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10
ohms....
Maybe just a length of nichrome wire?
Jonesy
On 21 Dec 2024 22:30:23 GMT, Allodoxaphobia <trepidation@example.net>
wrote:
On Sat, 21 Dec 2024 21:37:59 +0000, Cursitor Doom wrote:
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10
ohms....
Maybe just a length of nichrome wire?
Still got parasitics. Avoiding them is a craft in itself.
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably
Do we have any French speakers on the Panel? I have a radio that's
badly in need of realignment and the only instructions I can find are >> >>>> a set in French. I can't use Google translate because they've used too >> >>>> many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort >> >>> out some technical instructions in French If you want to send them to >> >>> me, I'll have a go (you should be able to work out my e-mail address). >> >>
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some
of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >819-line high-definition television service which had been translated
from French by someone who knew nothing about television or radio >terminologyy. It was hilarious nonsense but I eventually managed to >translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Cursitor Doom <cd@notformail.com> wrote:
On 21 Dec 2024 22:30:23 GMT, Allodoxaphobia <trepidation@example.net>
wrote:
On Sat, 21 Dec 2024 21:37:59 +0000, Cursitor Doom wrote:
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10
ohms....
Maybe just a length of nichrome wire?
Still got parasitics. Avoiding them is a craft in itself.
I wouldn't worry about the inductance of an ordianry 1/4 -Watt resistor
at the frequencies involved. The only point where it might make any >difference is the VHF input and oscillator tuning - and I can't think
you need a great level of accuracy to align a domestic portable radio.
It is even possible that they specified a 60-ohm sig gen because they
knew that most of the available ones would be near enough at either 50
or 75 0hms. Another possibility would be to try to make you think you
had to return the radio to their specialised service department for
repair. The avarage radio shop (if there are any left) simply wouldn't
care and would use whatever they had on the shelf above the workbench
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:Many thanks indeed for your kind offer. I suspect it will probably >>>>> require a native French speaker to decypher, but who knows? :-)
Do we have any French speakers on the Panel? I have a radio that's >>>>>>> badly in need of realignment and the only instructions I can find are >>>>>>> a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address). >>>>>
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some >>> of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French
819-line high-definition television service which had been translated >>from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >> >>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's >> >>>>>>> badly in need of realignment and the only instructions I can find are
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense.
I'm not a particularly fluent French speaker, but I could probably sort
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably
require a native French speaker to decypher, but who knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some >> >>> of the background you've revealed here in the past. I don't have the
relevant page here right now, but will make it available tomorrow. It
is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >> >> 819-line high-definition television service which had been translated
from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have >taken. Although we began with exactly the same source material, we have >produced two markedly different ways of saying the same thing.
On Sun, 22 Dec 2024 12:37:37 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >> >>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio
that's badly in need of realignment and the only instructions I
can find are a set in French. I can't use Google translate
because they've used too many abbreviations in the text and
they won't parse any sense.
I'm not a particularly fluent French speaker, but I could
probably sort out some technical instructions in French If you
want to send them to me, I'll have a go (you should be able to
work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will
probably require a native French speaker to decypher, but who
knows? :-)
I'm not a native French speaker, but I may be able to help anyway.
Fire away.
Well that's interesing as I had did think you might respond given some >> >>> of the background you've revealed here in the past. I don't have the >> >>> relevant page here right now, but will make it available tomorrow. It >> >>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks
ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >> >> 819-line high-definition television service which had been translated >> >>from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to
translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have >taken. Although we began with exactly the same source material, we have >produced two markedly different ways of saying the same thing.
Well, the important thing is that you agree on the key points.
Now it just so happens I have a vintage wobbulator (made by Knight
IIRC) which would be ideal for this job. It hasn't been used for about
20 years so it'll probably explode at switch-on, but that's nothing
unusual around here as my neighbours will attest.
On Sun, 22 Dec 2024 12:37:37 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>>>> (Liz Tuddenham) wrote:I'm not a native French speaker, but I may be able to help anyway. >>>>>>> Fire away.
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>>>> badly in need of realignment and the only instructions I can find areI'm not a particularly fluent French speaker, but I could probably sort
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense. >>>>>>>>>
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably >>>>>>>> require a native French speaker to decypher, but who knows? :-) >>>>>>>
Well that's interesing as I had did think you might respond given some >>>>>> of the background you've revealed here in the past. I don't have the >>>>>> relevant page here right now, but will make it available tomorrow. It >>>>>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks >>>>>> ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can >>>>>> speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >>>>> 819-line high-definition television service which had been translated >>>> >from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to >>>>> translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have
taken. Although we began with exactly the same source material, we have
produced two markedly different ways of saying the same thing.
Well, the important thing is that you agree on the key points.
Now it just so happens I have a vintage wobbulator (made by Knight
IIRC) which would be ideal for this job. It hasn't been used for about
20 years so it'll probably explode at switch-on, but that's nothing
unusual around here as my neighbours will attest.
Cursitor Doom <cd@notformail.com> wrote:
On Sun, 22 Dec 2024 12:37:37 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio
that's badly in need of realignment and the only instructions I >> >> >>>>>>> can find are a set in French. I can't use Google translate
because they've used too many abbreviations in the text and
they won't parse any sense.
I'm not a particularly fluent French speaker, but I could
probably sort out some technical instructions in French If you >> >> >>>>>> want to send them to me, I'll have a go (you should be able to
work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will
probably require a native French speaker to decypher, but who
knows? :-)
I'm not a native French speaker, but I may be able to help anyway. >> >> >>>> Fire away.
Well that's interesing as I had did think you might respond given some
of the background you've revealed here in the past. I don't have the >> >> >>> relevant page here right now, but will make it available tomorrow. It >> >> >>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks >> >> >>> ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can
speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French
819-line high-definition television service which had been translated >> >> >>from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to >> >> >> translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in >> >> > school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have
taken. Although we began with exactly the same source material, we have
produced two markedly different ways of saying the same thing.
Well, the important thing is that you agree on the key points.
Now it just so happens I have a vintage wobbulator (made by Knight
IIRC) which would be ideal for this job. It hasn't been used for about
20 years so it'll probably explode at switch-on, but that's nothing
unusual around here as my neighbours will attest.
Just to reinforce the point that Jeroen made, the adjustments interact,
so you will have to hop back and forth until the error becomes
negligible. As far as I know. nobody has ever found a way around this
and it takes up a lot of time at the end of a production line.
A piece of equipment, which was a great help when I had that unenviable
job, was a signal generator with push buttons to rapidly and reliably
switch between the end-of-band spot frequencies. I still had to wind
the dial drive from one end to the other each time - the reduction ratio
was 110:1. (See <https://eddystoneusergroup.org.uk/Data Sheets/EC10 Oct >1967.pdf>.)
On Sun, 22 Dec 2024 12:37:37 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>>>> (Liz Tuddenham) wrote:I'm not a native French speaker, but I may be able to help anyway. >>>>>>> Fire away.
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>>>> badly in need of realignment and the only instructions I can find areI'm not a particularly fluent French speaker, but I could probably sort
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense. >>>>>>>>>
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably >>>>>>>> require a native French speaker to decypher, but who knows? :-) >>>>>>>
Well that's interesing as I had did think you might respond given some >>>>>> of the background you've revealed here in the past. I don't have the >>>>>> relevant page here right now, but will make it available tomorrow. It >>>>>> is only the one page and only one column of that, so nothing too
onerous. I did show it to a genuine French chum of mine a few weeks >>>>>> ago, but he was stumped by the technical side of it and couldn't
assist much, unfortunately. So it appears it needs someone who can >>>>>> speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >>>>> 819-line high-definition television service which had been translated >>>> >from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to >>>>> translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in
school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII
for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have
taken. Although we began with exactly the same source material, we have
produced two markedly different ways of saying the same thing.
Well, the important thing is that you agree on the key points.
Now it just so happens I have a vintage wobbulator (made by Knight
IIRC) which would be ideal for this job. It hasn't been used for about
20 years so it'll probably explode at switch-on, but that's nothing
unusual around here as my neighbours will attest.
On 12/22/24 14:27, Cursitor Doom wrote:
On Sun, 22 Dec 2024 12:37:37 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Jeroen Belleman <jeroen@nospam.please> wrote:
On 12/21/24 14:57, Cursitor Doom wrote:
On Sat, 21 Dec 2024 08:57:51 +0000, liz@poppyrecords.invalid.invalid >>>>> (Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 00:05:08 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/20/24 22:16, Cursitor Doom wrote:
On Fri, 20 Dec 2024 19:32:14 +0000, liz@poppyrecords.invalid.invalid >>>>>>>>> (Liz Tuddenham) wrote:I'm not a native French speaker, but I may be able to help anyway. >>>>>>>> Fire away.
Cursitor Doom <cd@notformail.com> wrote:
Do we have any French speakers on the Panel? I have a radio that's >>>>>>>>>>> badly in need of realignment and the only instructions I can find areI'm not a particularly fluent French speaker, but I could probably sort
a set in French. I can't use Google translate because they've used too
many abbreviations in the text and they won't parse any sense. >>>>>>>>>>
out some technical instructions in French If you want to send them to
me, I'll have a go (you should be able to work out my e-mail address).
Many thanks indeed for your kind offer. I suspect it will probably >>>>>>>>> require a native French speaker to decypher, but who knows? :-) >>>>>>>>
Well that's interesing as I had did think you might respond given some >>>>>>> of the background you've revealed here in the past. I don't have the >>>>>>> relevant page here right now, but will make it available tomorrow. It >>>>>>> is only the one page and only one column of that, so nothing too >>>>>>> onerous. I did show it to a genuine French chum of mine a few weeks >>>>>>> ago, but he was stumped by the technical side of it and couldn't >>>>>>> assist much, unfortunately. So it appears it needs someone who can >>>>>>> speak French fluently *and* understands the process of radio
alignment. I kind of guessed that might be you....
Many years ago Practical Wireless published an article about the French >>>>>> 819-line high-definition television service which had been translated >>>>> >from French by someone who knew nothing about television or radio
terminologyy. It was hilarious nonsense but I eventually managed to >>>>>> translate it back into French so that I could understand it.
If you post your text here, we can all have a go at it.
Sorry for the delay; took a bit of tracking down but I have it now:
https://disk.yandex.com/i/3SiZ6rN_k-fP4w
It's only page 1 that needs the translation - and of that, in
particular the abbreviated bits. I haven't read French since I was in >>>>> school about a hundred years ago, so it's all Dutch to me. :-)
This was translated from German into French by someone who also
did not know clearly what it all meant. Not everything makes
perfect sense.
Also, while it doesn't say so, many of the adjustments interact,
so you may have to go back and forth a few times. Anyway, here
goes.
Jeroen Belleman
===============================================================
-- DC current adjustments (for 9V supply)
- Adjustment of the push-pull audio stage:
Cut the solder bridge marked -x- in the collector trace of the
AC188 T11 and insert a current meter. Adjust R410 for 6.5mA.
Restore the bridge.
- Adjustment of the IF amplifier:
Set R515 to obtain 1.35V across T4's emitter resistor R518.
-- Adjustment of the FM-IF stages. The radio should be set to "FM".
Connect a wobbulator centered on 10.7MHz at MP5 and the diode
detector shown at ZF VII (I think...) MP6. Detune ZF VIII (a).
Then tune ZFVII (b) for a symmetrical maximum response.
- Inject signal at MP3 and tune ZF VI (c) and ZF V (d) for
symmetrical maximum response.
- Inject signal on MP2 and adjust ZF IV (e) and ZF III (f) for
symmetrical maximum response.
- Inject a weakly coupled signal at the mixer (MP1?) and adjust
ZF II (g) and ZF I (h) for symmetrical maximum response.
- Discriminator: Inject signal at MP5, with a level low
enough that no limiting occurs in the IF strip. Observe the
signal at MP11 (audio amplifier input) with load impedance 50k.
Adjust ZF VIII (a) for symmetrical response.
-- Adjustment of the AM IF (460kHz) stages. The radio should be
set to "PO" (AM, 560-1450kHz). Connect a measurement instrument
at MP4 (Weakly coupled).
- Inject a wobbulator signal at MP3 and adjust ZF XIII and ZF XII >>>> for symmetrical maximum response.
- Inject signal at MP8 and adjust ZF XI for symmetrical maximum
response.
- Inject signal at MP7 and adjust ZF X and ZF IX for symmetrical
maximum response.
-- Adjustment of local oscillator and AM input. For short and
medium wave, couple signal into the ferrite rod antenna using
the frame. For short wave, remove the rod antenna and couple
signal at the antenna connection through 15pF.
Tune to 560kHz and adjust (1) and (3) for maximum response.
Mixer sensitivity 13uV and oscillator output 60-90mV.
Tune to 1450 kHz and adjust (2) and (4) for maximum response.
- Set the radio to GO (Long wave, 160-240kHz).
Tune to 160kHz and adjust (5) and (6) for maximum response.
Mixer sensitivity 13uV and oscillator output 65-95mV.
- Set the radio to OC (Short wave, 6.5-15MHz)
Tune to 6.5MHz and adjust (8) and (10) for maximum response.
Tune to 15MHz and adjust (9) and (11) for maximum response.
Mixer sensitivity 5uV and oscillator output 35-90mV.
-- Adjustment of the FM LO. Signal from an RF generator with
60 Ohm output impedance injected directly at the mixer (MP1?)
with a loaded signal level <2mV. Set the radio to FM.
- Tune to 88MHz and adjust (A) and (C) for maximum response.
- Tune to 106MHz and adjust (B) and (D) for maximum response,
Noise level is about 5 times kT0. Oscillator output voltage
75-85mV (at T2's emitter).
It is interesting to compare the different approaches Jeroen and I have
taken. Although we began with exactly the same source material, we have >>> produced two markedly different ways of saying the same thing.
Well, the important thing is that you agree on the key points.
Now it just so happens I have a vintage wobbulator (made by Knight
IIRC) which would be ideal for this job. It hasn't been used for about
20 years so it'll probably explode at switch-on, but that's nothing
unusual around here as my neighbours will attest.
I went back and forth between the text and the schematics to
try and clear up some inaccuracies in the text. Comparing with
the original German text, the G->F translator did an honourable
job, in fact.
I believe you have a VNA. I'd use that instead of a wobbulator.
You won't need the diode detector then. You'll need a high-Z
probe though. You'll also need an oscilloscope to observe the
audio amplifier input (to adjust the discriminator).
Jeroen Belleman
Maybe you should first build a dim bulb tester. Among other
things, it would enable you to re-form the power supply caps
it old gear and save an explosion or three. :-)
Many hits on a Google search, here's the first one: >https://antiqueradio.org/dimbulb.htm
Ed
Cursitor Doom <cd@notformail.com> wrote:
On 21 Dec 2024 22:30:23 GMT, Allodoxaphobia <trepidation@example.net>
wrote:
On Sat, 21 Dec 2024 21:37:59 +0000, Cursitor Doom wrote:
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10
ohms....
Maybe just a length of nichrome wire?
Still got parasitics. Avoiding them is a craft in itself.
I wouldn't worry about the inductance of an ordianry 1/4 -Watt resistor
at the frequencies involved. The only point where it might make any difference is the VHF input and oscillator tuning - and I can't think
you need a great level of accuracy to align a domestic portable radio.
It is even possible that they specified a 60-ohm sig gen because they
knew that most of the available ones would be near enough at either 50
or 75 0hms. Another possibility would be to try to make you think you
had to return the radio to their specialised service department for
repair. The avarage radio shop (if there are any left) simply wouldn't
care and would use whatever they had on the shelf above the workbench.
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson >><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>><cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >>>><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>PTFE dielectric in the 75 has been minimised in order to increase (with >>>>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>>>more-uniform structural RLR, so it the better connector at the higher >>>>>frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>>presume it's not practicable to make the pin diameter smaller and retain >>>its robustness, so the only way to increase the Zo is to remove as much >>>of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I >>stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
On 2024-12-25, john larkin <JL@gct.com> wrote:
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson >>><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>>><cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >>>>><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>>PTFE dielectric in the 75 has been minimised in order to increase (with >>>>>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>>>>more-uniform structural RLR, so it the better connector at the higher >>>>>>frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>>conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>>>presume it's not practicable to make the pin diameter smaller and retain >>>>its robustness, so the only way to increase the Zo is to remove as much >>>>of the dielectric as possible. If you compare the 50 and the 75, you >>>>will see what I mean.
I still maintain the principal determinants of the impedance are as I >>>stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
this seems to be something related to their units conversion. If you use >millimeters it gives sensible-looking answers.
On Sun, 22 Dec 2024 12:57:54 -0500, ehsjr <ehsjr@verizon.net> wrote:
Maybe you should first build a dim bulb tester. Among other
things, it would enable you to re-form the power supply caps
it old gear and save an explosion or three. :-)
Many hits on a Google search, here's the first one:
https://antiqueradio.org/dimbulb.htm
Ed
I did actually build one a few years ago with swappable bulbs for
different loads. Two problems, though:
1) I'd have to remember to use it
2) I'd have to somehow find it.
On 22/12/2024 22:50, Cursitor Doom wrote:
On Sun, 22 Dec 2024 12:57:54 -0500, ehsjr <ehsjr@verizon.net> wrote:
Maybe you should first build a dim bulb tester. Among other
things, it would enable you to re-form the power supply caps
it old gear and save an explosion or three. :-)
Many hits on a Google search, here's the first one:
https://antiqueradio.org/dimbulb.htm
Ed
I did actually build one a few years ago with swappable bulbs for
different loads. Two problems, though:
1) I'd have to remember to use it
2) I'd have to somehow find it.
I think that you might have to add a third one in future - finding an >incandescent bulb to use!
Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
Cursitor Doom <cd@notformail.com> wrote:60 ohms was a popular impedance for RF test gear in Europe in the 1950s and >60s
On 21 Dec 2024 22:30:23 GMT, Allodoxaphobia <trepidation@example.net>
wrote:
On Sat, 21 Dec 2024 21:37:59 +0000, Cursitor Doom wrote:
in series with your 50 Ohm source.
Yes, but you know what a *bitch* it is to find a purely resistive 10 >>>>> ohms....
Maybe just a length of nichrome wire?
Still got parasitics. Avoiding them is a craft in itself.
I wouldn't worry about the inductance of an ordianry 1/4 -Watt resistor
at the frequencies involved. The only point where it might make any
difference is the VHF input and oscillator tuning - and I can't think
you need a great level of accuracy to align a domestic portable radio.
It is even possible that they specified a 60-ohm sig gen because they
knew that most of the available ones would be near enough at either 50
or 75 0hms. Another possibility would be to try to make you think you
had to return the radio to their specialised service department for
repair. The avarage radio shop (if there are any left) simply wouldn't
care and would use whatever they had on the shelf above the workbench.
For many purposes you can ignore the difference between the 50 and 75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are mutually mechanically mateable (yes - they really are!). I don't know if any others that are.
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and 75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are mutually mechanically mateable (yes - they really are!). I don't know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75 ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV company), the rest is 50.
On Mon, 23 Dec 2024 08:16:15 +0000, Jeff Layman <Jeff@invalid.invalid>
wrote:
On 22/12/2024 22:50, Cursitor Doom wrote:
On Sun, 22 Dec 2024 12:57:54 -0500, ehsjr <ehsjr@verizon.net> wrote:
Maybe you should first build a dim bulb tester. Among other
things, it would enable you to re-form the power supply caps
it old gear and save an explosion or three. :-)
Many hits on a Google search, here's the first one:
https://antiqueradio.org/dimbulb.htm
Ed
I did actually build one a few years ago with swappable bulbs for
different loads. Two problems, though:
1) I'd have to remember to use it
2) I'd have to somehow find it.
I think that you might have to add a third one in future - finding an >>incandescent bulb to use!
Yes, getting harder as time goes by, so I stocked-up in advance and
put a couple of dozen aside while they were still widely available. I
would imagine the oven types will still be around for a few more
years, anyway - and they tend to be more robust.
In article <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, noreply@ademu.nl
says...
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and 75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are mutually mechanically mateable (yes - they really are!). I don't know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75 ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV company), the rest is 50.
It is the N connector the center pin is different. The BNC pin is the
same. It is the ammount of dialectric (insulation) in the BNC that
makes it a 75 or 50 ohm connector.
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and 75
ohm impedances (and 60 if you ever come across any). However, be very
aware only BNC 50 and 75 ohm connectors are mutually mechanically
mateable (yes - they really are!). I don't know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75
ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >company), the rest is 50.
In article <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, noreply@ademu.nl
says...
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and
75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are
mutually mechanically mateable (yes - they really are!). I don't
know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a
75 ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >>company), the rest is 50.
It is the N connector the center pin is different.
The BNC pin is the--
same. It is the ammount of dialectric (insulation) in the BNC that
makes it a 75 or 50 ohm connector.
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with
some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >frequencies.
On 12/23/24 18:58, Ralph Mowery wrote:
In article <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, noreply@ademu.nl
says...
It is the N connector the center pin is different. The BNC pin is
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and
75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are
mutually mechanically mateable (yes - they really are!). I don't
know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a
75 ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >>>company), the rest is 50.
the
same. It is the ammount of dialectric (insulation) in the BNC that
makes it a 75 or 50 ohm connector.
N connectors are good, but the fact that 75 and 50 Ohm connectors
are similar enough to mate, but not nearly enough to do so without
damage or malfunction is perverse. When I took charge of the
electronics lab, it took a while to sort them out and to eliminate
the victims of mismatched matings. (I was always amazed at the
sheer quantity of connectors in a busy lab.)
For BNCs, there *is* a difference, but it doesn't usually matter.
I kept 50 and 75 Ohms separate, but when put to the test, many
75 Ohm connectors turned out to really be 50 Ohm ones in disguise.
In a pinch, BNC and N can even mate between them. I'm not sure if
that's deliberate or accidental.
In message <vkckph$1cvdj$1@dont-email.me>, Jeroen Belleman <jeroen@nospam.please> writes
On 12/23/24 18:58, Ralph Mowery wrote:Yes - the 'innards' are essentially the same. IIRC, the BNC innards also
In article <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, noreply@ademu.nl
says...
It is the N connector the center pin is different. The BNC pin is
On 2024-12-23 16:22, Ian Jackson wrote:
For many purposes you can ignore the difference between the 50 and
75 ohm impedances (and 60 if you ever come across any).
However, be very aware only BNC 50 and 75 ohm connectors are
mutually mechanically mateable (yes - they really are!). I don't
know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a
75 ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV
company), the rest is 50.
the
same. It is the ammount of dialectric (insulation) in the BNC that
makes it a 75 or 50 ohm connector.
N connectors are good, but the fact that 75 and 50 Ohm connectors
are similar enough to mate, but not nearly enough to do so without
damage or malfunction is perverse. When I took charge of the
electronics lab, it took a while to sort them out and to eliminate
the victims of mismatched matings. (I was always amazed at the
sheer quantity of connectors in a busy lab.)
For BNCs, there *is* a difference, but it doesn't usually matter.
I kept 50 and 75 Ohms separate, but when put to the test, many
75 Ohm connectors turned out to really be 50 Ohm ones in disguise.
In a pinch, BNC and N can even mate between them. I'm not sure if
that's deliberate or accidental.
mate with C-connectors. I think it's deliberate. After all, its the
innards that carry the RF.
On Mon, 23 Dec 2024 08:16:15 +0000, Jeff Layman <Jeff@invalid.invalid>
I did actually build one a few years ago with swappable bulbs for
different loads. Two problems, though:
1) I'd have to remember to use it
2) I'd have to somehow find it.
I think that you might have to add a third one in future - finding an
incandescent bulb to use!
Yes, getting harder as time goes by, so I stocked-up in advance and
put a couple of dozen aside while they were still widely available. I
would imagine the oven types will still be around for a few more
years, anyway - and they tend to be more robust.
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson ><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with >>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>frequencies.
I don't think that's quite right. The diameter of the inner and outer >conductors has more influence on Zo than the dilectric thickness.
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom ><cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with >>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>more-uniform structural RLR, so it the better connector at the higher >>>frequencies.
I don't think that's quite right. The diameter of the inner and outer >>conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I
presume it's not practicable to make the pin diameter smaller and retain
its robustness, so the only way to increase the Zo is to remove as much
of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
On 23/12/2024 10:31, Cursitor Doom wrote:
On Mon, 23 Dec 2024 08:16:15 +0000, Jeff Layman <Jeff@invalid.invalid>
I did actually build one a few years ago with swappable bulbs for
different loads. Two problems, though:
1) I'd have to remember to use it
2) I'd have to somehow find it.
I think that you might have to add a third one in future - finding an
incandescent bulb to use!
Yes, getting harder as time goes by, so I stocked-up in advance and
put a couple of dozen aside while they were still widely available. I
would imagine the oven types will still be around for a few more
years, anyway - and they tend to be more robust.
I doubt they'll be able to replace the oven illumination easily (unless
they mount the bulb on the outside and use fibreoptics to bring light to
the inside!). I was surprised a few months ago when I bought a new
microwave oven to find it had an LED lamp which illuminated the inside.
I would have thought that with around a kW of microwave energy being >generated that would have been a pretty hostile environment for an LED
lamp. Obviously, though, they had the screening well sorted out. I
suppose that I shouldn't have been surprised as the timing and display >circuitry have been around for years and hasn't been affected by the RF >energy or switching spikes.
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson <ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom
<cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with >>>> some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher
frequencies.
I don't think that's quite right. The diameter of the inner and outer
conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I
presume it's not practicable to make the pin diameter smaller and retain
its robustness, so the only way to increase the Zo is to remove as much
of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
In message <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, Arie de Muijnck ><noreply@ademu.nl> writes
On 2024-12-23 16:22, Ian Jackson wrote:For most of its length, the male BNC 50 ohm pin is actually the same
For many purposes you can ignore the difference between the 50 and 75 >>>ohm impedances (and 60 if you ever come across any). However, be very >>>aware only BNC 50 and 75 ohm connectors are mutually mechanically >>>mateable (yes - they really are!). I don't know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75
ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >>company), the rest is 50.
diameter as the 75. However, the tip of the 50 pin is fairly 'blunt',
while the 75 is more pointed.
I guess that if you are particularly clumsy while you are inserting a 50
male into a female 75, it might just be possible to have the blunter
male pin a bit off-centre, and catch the side of the female receptacle,
and splay it. However, despite 43 years working in the CATV industry, I >failed to achieve this!
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with
some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >frequencies.
In article <8i6omj1vidqoch9421207205iajrb0h5ue@4ax.com>,
cd@notformail.com says...
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
I could not get the calculator to come out for me. Getting negative
numbers and about 10 times what they should be.
In message <l7vomj55u59o3cu753v7de77t0j4n20jtp@4ax.com>, john larkin ><JL@gct.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, Arie de Muijnck >>><noreply@ademu.nl> writes
On 2024-12-23 16:22, Ian Jackson wrote:For most of its length, the male BNC 50 ohm pin is actually the same >>>diameter as the 75. However, the tip of the 50 pin is fairly 'blunt', >>>while the 75 is more pointed.
For many purposes you can ignore the difference between the 50 and 75 >>>>>ohm impedances (and 60 if you ever come across any). However, be very >>>>>aware only BNC 50 and 75 ohm connectors are mutually mechanically >>>>>mateable (yes - they really are!). I don't know if any others that are. >>>>Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75 >>>>ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >>>>company), the rest is 50.
I guess that if you are particularly clumsy while you are inserting a 50 >>>male into a female 75, it might just be possible to have the blunter
male pin a bit off-centre, and catch the side of the female receptacle, >>>and splay it. However, despite 43 years working in the CATV industry, I >>>failed to achieve this!
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with >>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>more-uniform structural RLR, so it the better connector at the higher >>>frequencies.
The critical part of the connector here is a fraction of an inch long,
so none of this stuff matters below a few GHz.
Yes. Obviously.
I've been retired now for many a year but, IIRC, the 50 ohm was
considered 'good' to around 1000 MHz, and the 75 to around 500MHz. [A
Google on the individual manufacturers' specs is recommended.]
Regardless, both are often used to higher frequencies.
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson ><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >><cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >>><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>PTFE dielectric in the 75 has been minimised in order to increase (with >>>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>>more-uniform structural RLR, so it the better connector at the higher >>>>frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>presume it's not practicable to make the pin diameter smaller and retain >>its robustness, so the only way to increase the Zo is to remove as much
of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson ><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >><cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson >>><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>PTFE dielectric in the 75 has been minimised in order to increase (with >>>>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>>more-uniform structural RLR, so it the better connector at the higher >>>>frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>presume it's not practicable to make the pin diameter smaller and retain >>its robustness, so the only way to increase the Zo is to remove as much
of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson ><ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <nnd$23e91f0d$053bf96e@d25fd620e9918bf1>, Arie de Muijnck >><noreply@ademu.nl> writes
On 2024-12-23 16:22, Ian Jackson wrote:For most of its length, the male BNC 50 ohm pin is actually the same >>diameter as the 75. However, the tip of the 50 pin is fairly 'blunt',
For many purposes you can ignore the difference between the 50 and 75 >>>>ohm impedances (and 60 if you ever come across any). However, be very >>>>aware only BNC 50 and 75 ohm connectors are mutually mechanically >>>>mateable (yes - they really are!). I don't know if any others that are.
Not recommended.
The center pin differs, a 50 Ohm BNC pin is thicker and may damage a 75 >>>ohm BNC.
I'm cautious, most of my below 1 GHz equipment is 75 Ohms (from CATV >>>company), the rest is 50.
while the 75 is more pointed.
I guess that if you are particularly clumsy while you are inserting a 50 >>male into a female 75, it might just be possible to have the blunter
male pin a bit off-centre, and catch the side of the female receptacle,
and splay it. However, despite 43 years working in the CATV industry, I >>failed to achieve this!
The real difference between the two impedances is that the amount of
PTFE dielectric in the 75 has been minimised in order to increase (with >>some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>frequencies.
The critical part of the connector here is a fraction of an inch long,
so none of this stuff matters below a few GHz.
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom
<cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>> PTFE dielectric in the 75 has been minimised in order to increase (with >>>>> some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>>>> frequencies.
I don't think that's quite right. The diameter of the inner and outer
conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I
presume it's not practicable to make the pin diameter smaller and retain >>> its robustness, so the only way to increase the Zo is to remove as much
of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
On 12/26/24 00:15, john larkin wrote:
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>Negative values for Z0? That would be surprising, because
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>>> <cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>> PTFE dielectric in the 75 has been minimised in order to increase (with >>>>>> some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>>>>> frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>> conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I
presume it's not practicable to make the pin diameter smaller and retain >>>> its robustness, so the only way to increase the Zo is to remove as much >>>> of the dielectric as possible. If you compare the 50 and the 75, you
will see what I mean.
I still maintain the principal determinants of the impedance are as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
the equation is correct, even though the physics are
obfuscated away into a few magic factors.
Example please?
Jeroen Belleman
On Fri, 27 Dec 2024 16:23:58 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/26/24 00:15, john larkin wrote:
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>Negative values for Z0? That would be surprising, because
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>>>> <cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>>> PTFE dielectric in the 75 has been minimised in order to increase (with >>>>>>> some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>>>>>> frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>>> conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>>>> presume it's not practicable to make the pin diameter smaller and retain >>>>> its robustness, so the only way to increase the Zo is to remove as much >>>>> of the dielectric as possible. If you compare the 50 and the 75, you >>>>> will see what I mean.
I still maintain the principal determinants of the impedance are as I >>>> stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
the equation is correct, even though the physics are
obfuscated away into a few magic factors.
Example please?
Jeroen Belleman
https://www.dropbox.com/scl/fi/aglpygrtir3m9bccil1to/EvRfZcalc.jpg?rlkey=nazlwgbmpvbssz5zv2a92hrqj&raw=1
On Fri, 27 Dec 2024 16:23:58 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/26/24 00:15, john larkin wrote:
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>Negative values for Z0? That would be surprising, because
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>>>> <cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>>> PTFE dielectric in the 75 has been minimised in order to increase (with >>>>>>> some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a
more-uniform structural RLR, so it the better connector at the higher >>>>>>> frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>>> conductors has more influence on Zo than the dilectric thickness.
It's right all right.
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>>>> presume it's not practicable to make the pin diameter smaller and retain >>>>> its robustness, so the only way to increase the Zo is to remove as much >>>>> of the dielectric as possible. If you compare the 50 and the 75, you >>>>> will see what I mean.
I still maintain the principal determinants of the impedance are as I >>>> stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and
a preposterous cutoff frequency.
the equation is correct, even though the physics are
obfuscated away into a few magic factors.
Example please?
Jeroen Belleman
https://www.dropbox.com/scl/fi/aglpygrtir3m9bccil1to/EvRfZcalc.jpg?rlkey=nazlwgbmpvbssz5zv2a92hrqj&raw=1
On Fri, 27 Dec 2024 08:21:55 -0800, john larkin <JL@gct.com> wrote:
On Fri, 27 Dec 2024 16:23:58 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:
On 12/26/24 00:15, john larkin wrote:
On Wed, 25 Dec 2024 14:48:20 +0000, Cursitor Doom <cd@notformail.com>Negative values for Z0? That would be surprising, because
wrote:
On Tue, 24 Dec 2024 22:42:17 +0000, Ian Jackson
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
In message <6ftjmjppf4421dl2ec0ek4mvfht74lmnu2@4ax.com>, Cursitor Doom >>>>>> <cd@notformail.com> writes
On Mon, 23 Dec 2024 23:05:03 +0000, Ian JacksonIt's right all right.
<ianREMOVETHISjackson@g3ohx.co.uk> wrote:
The real difference between the two impedances is that the amount of >>>>>>>> PTFE dielectric in the 75 has been minimised in order to increase (with
some difficulty) the Zo from 50 to 75 ohms. IIRC, the 50 has a >>>>>>>> more-uniform structural RLR, so it the better connector at the higher >>>>>>>> frequencies.
I don't think that's quite right. The diameter of the inner and outer >>>>>>> conductors has more influence on Zo than the dilectric thickness. >>>>>>
The outer diameter is the same for the 50 and 75 ohms. For the 75, I >>>>>> presume it's not practicable to make the pin diameter smaller and retain >>>>>> its robustness, so the only way to increase the Zo is to remove as much >>>>>> of the dielectric as possible. If you compare the 50 and the 75, you >>>>>> will see what I mean.
I still maintain the principal determinants of the impedance are as I >>>>> stated previously. The formulas for line impedance are shown on this >>>>> page and the aforementioned determinants are key.
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
That calc is nonsense. Reasonable entries generate negative values and >>>> a preposterous cutoff frequency.
the equation is correct, even though the physics are
obfuscated away into a few magic factors.
Example please?
Jeroen Belleman
https://www.dropbox.com/scl/fi/aglpygrtir3m9bccil1to/EvRfZcalc.jpg?rlkey=nazlwgbmpvbssz5zv2a92hrqj&raw=1
GIGO. Where on earth did you get those input parameter values from?
Try it again with something more realistic.
