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john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
There some pretty big ones in the nearby substation but I can't get near >enough to read the rating plates.
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
On 17/12/2024 15:44, john larkin wrote:
On Tue, 17 Dec 2024 15:30:30 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
There some pretty big ones in the nearby substation but I can't get near >>> enough to read the rating plates.
They probably wouldn't state the inductance.
One outfit that makes utility transformer test sets say that their
gadgets measure up to 10H. I was hoping to find something outrageous.
Hammond makes a 200H inductor. It is NOT good for 30 amps!
https://www.digikey.com/en/products/detail/hammond-manufacturing/193A/16939893
The superconducting magnets used in MRI machines have a very high
inductance. I have seen values between 50 and 100H quoted.
John
On Tue, 17 Dec 2024 15:30:30 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
There some pretty big ones in the nearby substation but I can't get near
enough to read the rating plates.
They probably wouldn't state the inductance.
One outfit that makes utility transformer test sets say that their
gadgets measure up to 10H. I was hoping to find something outrageous.
Hammond makes a 200H inductor. It is NOT good for 30 amps!
https://www.digikey.com/en/products/detail/hammond-manufacturing/193A/16939893
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
On 12/17/2024 10:44 AM, john larkin wrote:
On Tue, 17 Dec 2024 15:30:30 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
There some pretty big ones in the nearby substation but I can't get near >>> enough to read the rating plates.
They probably wouldn't state the inductance.
One outfit that makes utility transformer test sets say that their
gadgets measure up to 10H. I was hoping to find something outrageous.
Hammond makes a 200H inductor. It is NOT good for 30 amps!
https://www.digikey.com/en/products/detail/hammond-manufacturing/193A/16939893
Someone's still building choke-loaded audio stages I guess. Them
newfangled CCS just aren't trustworthy
On 17/12/2024 14:58, john larkin wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
I think the Fermi Lab's Tevatron magnet at 1000H and 1500A is one of the >largest ever made but some of the latest GW class mains substation >transformers must have similar levels of inductance and stored energy.
See: >https://electronics.stackexchange.com/questions/303320/what-is-the-largest-inductance-value-ever-attained-in-henries
On 17/12/2024 14:58, john larkin wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
I think the Fermi Lab's Tevatron magnet at 1000H and 1500A is one of the >largest ever made but some of the latest GW class mains substation >transformers must have similar levels of inductance and stored energy.
See: >https://electronics.stackexchange.com/questions/303320/what-is-the-largest-inductance-value-ever-attained-in-henries
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
On Sat, 21 Dec 2024 14:28:52 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 17/12/2024 14:58, john larkin wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
I think the Fermi Lab's Tevatron magnet at 1000H and 1500A is one of the >>largest ever made but some of the latest GW class mains substation >>transformers must have similar levels of inductance and stored energy.
See: >>https://electronics.stackexchange.com/questions/303320/what-is-the-largest-inductance-value-ever-attained-in-henries
That's cool.
I guess an old neon sign transformer could have a huge inductance,
ballpark 1000 Henries maybe, assuming that leakage inductance is the
main current limiter.
I had a giant one when I was a kid, 15 KV with insulators on both
ends. The Jacobs Ladder arc must have been almost a foot long. Wish I
still had it.
I'm designing inducor sumulators and am curious about how big real
inductors ever get. My buddies at a big aerospace test outfit say they
don't see anything above 2 H.
On Sat, 21 Dec 2024 00:10:45 -0500, bitrex <user@example.net> wrote:
On 12/17/2024 10:44 AM, john larkin wrote:
On Tue, 17 Dec 2024 15:30:30 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
There some pretty big ones in the nearby substation but I can't get near >>>> enough to read the rating plates.
They probably wouldn't state the inductance.
One outfit that makes utility transformer test sets say that their
gadgets measure up to 10H. I was hoping to find something outrageous.
Hammond makes a 200H inductor. It is NOT good for 30 amps!
https://www.digikey.com/en/products/detail/hammond-manufacturing/193A/16939893
Someone's still building choke-loaded audio stages I guess. Them
newfangled CCS just aren't trustworthy
Inductors are the worst parts that we can buy. I can wave off the >imperfections in my inductor simulators by noting how bad real
inductors are.
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
Transformers don't store energy
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote:
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
On Sat, 21 Dec 2024 14:28:52 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 17/12/2024 14:58, john larkin wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
I think the Fermi Lab's Tevatron magnet at 1000H and 1500A is one of the >>largest ever made but some of the latest GW class mains substation >>transformers must have similar levels of inductance and stored energy.
See: >>https://electronics.stackexchange.com/questions/303320/what-is-the-largest-inductance-value-ever-attained-in-henries
Transformers don't store energy - large L has no particular benefit
in their design, save limiting magnetizing current to below a
certain acceptable level.
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote:
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
On Sat, 21 Dec 2024 11:35:54 -0800, john larkin <JL@gct.com> wrote:
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com> >wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote:
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I >>>>seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 11:35:54 -0800, john larkin <JL@gct.com> wrote:
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote:
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Have a look at:
<http://www.poppyrecords.co.uk/httpdocs/other/AMC5.pdf>
as an example of incredibly efficient design. It took the output from a >ribbon mic and raised it to 0dBm line level. By using a mixture of
current and voltage feedback, it terminated the mic correctly without
the need for a terminating resistor, which would have wasted signal
power and generated Johnson noise.
In article <3faemjtve5hvghau2up1stdid1u3bq84gd@4ax.com>,
Cursitor Doom <cd@notformail.com> wrote:
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
One trick I've seen mentioned in a couple of books, was to use a
single tube section as an amplifier for two entirely different stages
of a radio or TV receiver. The tube's grid was fed a combination of
an incoming IF signal, and audio output from the detector; the output
at the anode was fed to both the detector input, and to the audio
output (or a second, power-amplifier stage). Since the frequencies
were so greatly different it was possible to use not-too-awful filters
to combine and separate them, and they didn't interfere with one another >badly enough to keep the system from working.
Quite a different era from today, when they're talking about single
chips containing a trillion active devices!
In article <3faemjtve5hvghau2up1stdid1u3bq84gd@4ax.com>,
Cursitor Doom <cd@notformail.com> wrote:
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
One trick I've seen mentioned in a couple of books, was to use a
single tube section as an amplifier for two entirely different stages
of a radio or TV receiver. The tube's grid was fed a combination of
an incoming IF signal, and audio output from the detector; the output
at the anode was fed to both the detector input, and to the audio
output (or a second, power-amplifier stage). Since the frequencies
were so greatly different it was possible to use not-too-awful filters
to combine and separate them, and they didn't interfere with one another badly enough to keep the system from working.
Quite a different era from today, when they're talking about single
chips containing a trillion active devices!
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
On 12/22/24 00:03, Dave Platt wrote:
In article <3faemjtve5hvghau2up1stdid1u3bq84gd@4ax.com>,
Cursitor Doom <cd@notformail.com> wrote:
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
One trick I've seen mentioned in a couple of books, was to use a
single tube section as an amplifier for two entirely different stages
of a radio or TV receiver. The tube's grid was fed a combination of
an incoming IF signal, and audio output from the detector; the output
at the anode was fed to both the detector input, and to the audio
output (or a second, power-amplifier stage). Since the frequencies
were so greatly different it was possible to use not-too-awful filters
to combine and separate them, and they didn't interfere with one another
badly enough to keep the system from working.
Quite a different era from today, when they're talking about single
chips containing a trillion active devices!
In my early days as a budding electronics person, I played
with a television set that did that. The same tubes amplified
the video IF and the audio.
I also recall cheap toy walkie-talkies from the 1970s that
used a single transistor as both a super-regenerative
receiver and as a transmit oscillator.
In another thread just these last few days, Cursitor Doom
showed us a 1970s era Grundig radio that used the same
transistors for the 10.7MHz FM IF and the 460kHz AM IF.
I those days, transistors were expensive. Coils and
switches were cheap.
Jeroen Belleman
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 11:35:54 -0800, john larkin <JL@gct.com> wrote:
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote:
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? I
seem to recall some audio transformer that was something like 100 H.
The SAFT/Alcatel plant in Scarborough used to have
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Have a look at:
<http://www.poppyrecords.co.uk/httpdocs/other/AMC5.pdf>
as an example of incredibly efficient design. It took the output from a >ribbon mic and raised it to 0dBm line level. By using a mixture of
current and voltage feedback, it terminated the mic correctly without
the need for a terminating resistor, which would have wasted signal
power and generated Johnson noise.
On Sat, 21 Dec 2024 22:01:36 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 11:35:54 -0800, john larkin <JL@gct.com> wrote:
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote: >> >>
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? IThe SAFT/Alcatel plant in Scarborough used to have
seem to recall some audio transformer that was something like 100 H. >> >>>
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Have a look at:
<http://www.poppyrecords.co.uk/httpdocs/other/AMC5.pdf>
as an example of incredibly efficient design. It took the output from a >ribbon mic and raised it to 0dBm line level. By using a mixture of
current and voltage feedback, it terminated the mic correctly without
the need for a terminating resistor, which would have wasted signal
power and generated Johnson noise.
link not valid from here . . . .
On Sat, 21 Dec 2024 22:01:36 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
Cursitor Doom <cd@notformail.com> wrote:
On Sat, 21 Dec 2024 11:35:54 -0800, john larkin <JL@gct.com> wrote:
On Sat, 21 Dec 2024 16:53:07 +0000, Cursitor Doom <cd@notformail.com>
wrote:
On Sat, 21 Dec 2024 11:16:18 -0500, legg <legg@nospam.magma.ca> wrote: >>> >>
On Tue, 17 Dec 2024 06:58:32 -0800, john larkin <JL@gct.com> wrote:
What's the biggest inductor, the most Henries, that you know of? IThe SAFT/Alcatel plant in Scarborough used to have
seem to recall some audio transformer that was something like 100 H. >>> >>>
largish inductors for loading. Air-cored - ~10ft
on a side.
Your watch would stop, if you were too close.
Large L ? Who needs it?
In the olde days we used to have audio output transformers for
impedance matching purposes, but modern amps don't seem to need 'em.
And long ago tubes were expensive so it made sense to get voltage gain
from interstage transformers.
Indeed. And that's just one aspect of it. The designers in the early
stage of toob development deserve huge respect for the performance
they were able to wring out of a single stage - and all just to save
the hard-pressed consumer back in the day a few sheckles.
Have a look at:
<http://www.poppyrecords.co.uk/httpdocs/other/AMC5.pdf>
as an example of incredibly efficient design. It took the output from a >>ribbon mic and raised it to 0dBm line level. By using a mixture of
current and voltage feedback, it terminated the mic correctly without
the need for a terminating resistor, which would have wasted signal
power and generated Johnson noise.
link not valid from here . . . .
I only ever did commercially impractical valve circuits. Often
using one-off components that couldn't be replaced without
major toil.
One way of separating the hobby from work.
RL
legg <legg@nospam.magma.ca> wrote:
[...]
Transformers don't store energy
That's debatable.
