Well that was a fun exercise...
Some 18 years ago I put up a new aerial (group B with some bits hacked
off on Bill's instructions to tune it to act more like a group E).
Decent Proception masthead amp and power supply, 5 way inductive
splitter inside, and then runs off to various TV points. Pointed at
Sudbury some 35 miles away.
It has worked flawlessly ever since, not even phased by the various
bouts of Freeview channel shifting. Art least, that was until a couple
of days ago. Mother's TV was glitching and dropping out on most
channels. So fearing some woe had befallen the aerial or a co-ax, I got
out Terry, my trusty UHF signal meter, and plugged it into the drop wire >from the aerial, turned on the meter's 12V power supply, and low and
behold, six muxes, all at a solid 72 to 84dB, and all showing a "Pass" >quality.
So rejigged to allow the normal PSU to feed the masthead amp and
measured again - same result. Connected the splitter up and looked at
the output. Again a fine display of passes and levels showing 67 - 76
dB. Seemed pretty reasonable after a 5 way split. Then metered the
aerial socket near the TV, again spot on. Plugged it into the TV, glitch >city...
Noise getting in? The flylead was a cheap thin premade jobbie. So I made
up a nice new one with some WF100 double screened co-ax, and no better.
It was beginning to look like it might actually be a tuner fault on the
TV. Fortunately there was a spare one that I had recently pulled out of
an office prior to a re-furb. So I got that, set it up expecting better >results, and nope, exactly the same symptoms. Too much signal? Added a
6dB attenuator inline - nope that was worse.
I was now entering the clutching at straws phase. Could the amp's PSU be >injecting noise (18 year old caps and all that)? So I pulled that out
looked at its output on the DSO - smooth as a baby's bum.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi
access point at the back of the house a few days ago (long way from the
TV), however that also supported mesh operation, so I enabled that, and
then turned on the 5GHz wifi on the main router (previously I had that >turned off since it was tricky to get it to play nice with other 5GHz
access points without a mesh capability). So out of curiosity, I turned
off the 5GHz network on the main router, and tada! Problem sorted.
Odd it could upset two different sets placed about 6m and a couple of
walls away from the router, yet it did not upset the network TV tuner
sat 500mm away from the router (which I only thought to check later!)
Both oldish LG sets, but of different vintage.
In article <118usjp$17ta8$1@dont-email.me>, John Rumm <see.my.signature@ nowhere.null> scribeth thus
Well that was a fun exercise...How close to the TV and or aerial amp is this unit can you say?, as we
Some 18 years ago I put up a new aerial (group B with some bits hacked
off on Bill's instructions to tune it to act more like a group E).
Decent Proception masthead amp and power supply, 5 way inductive
splitter inside, and then runs off to various TV points. Pointed at
Sudbury some 35 miles away.
It has worked flawlessly ever since, not even phased by the various
bouts of Freeview channel shifting. Art least, that was until a couple
of days ago. Mother's TV was glitching and dropping out on most
channels. So fearing some woe had befallen the aerial or a co-ax, I got
out Terry, my trusty UHF signal meter, and plugged it into the drop wire >>from the aerial, turned on the meter's 12V power supply, and low and
behold, six muxes, all at a solid 72 to 84dB, and all showing a "Pass"
quality.
So rejigged to allow the normal PSU to feed the masthead amp and
measured again - same result. Connected the splitter up and looked at
the output. Again a fine display of passes and levels showing 67 - 76
dB. Seemed pretty reasonable after a 5 way split. Then metered the
aerial socket near the TV, again spot on. Plugged it into the TV, glitch
city...
Noise getting in? The flylead was a cheap thin premade jobbie. So I made
up a nice new one with some WF100 double screened co-ax, and no better.
It was beginning to look like it might actually be a tuner fault on the
TV. Fortunately there was a spare one that I had recently pulled out of
an office prior to a re-furb. So I got that, set it up expecting better
results, and nope, exactly the same symptoms. Too much signal? Added a
6dB attenuator inline - nope that was worse.
I was now entering the clutching at straws phase. Could the amp's PSU be
injecting noise (18 year old caps and all that)? So I pulled that out
looked at its output on the DSO - smooth as a baby's bum.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi
access point at the back of the house a few days ago (long way from the
TV), however that also supported mesh operation, so I enabled that, and
then turned on the 5GHz wifi on the main router (previously I had that
turned off since it was tricky to get it to play nice with other 5GHz
access points without a mesh capability). So out of curiosity, I turned
off the 5GHz network on the main router, and tada! Problem sorted.
Odd it could upset two different sets placed about 6m and a couple of
walls away from the router, yet it did not upset the network TV tuner
sat 500mm away from the router (which I only thought to check later!)
Both oldish LG sets, but of different vintage.
have higher powered 5.8 G links up on our TV aerial with no adverse u
issues it does seem rather odd I'd normally suspect that overloading the aerial amp and causing intermod ..
Mind you 35 miles away from that TX is likely to be a weak "ish" input signal, its not the most powerful one in the country!.
You sure you didn't mean Kilometres or by road?..
http://tx.mb21.co.uk/mapsys/map.php?mapid=95
On 22/09/2026 23:32, tony sayer wrote:
In article <118usjp$17ta8$1@dont-email.me>, John Rumm <see.my.signature@
nowhere.null> scribeth thus
Well that was a fun exercise...How close to the TV and or aerial amp is this unit can you say?, as we
Some 18 years ago I put up a new aerial (group B with some bits hacked
off on Bill's instructions to tune it to act more like a group E).
Decent Proception masthead amp and power supply, 5 way inductive
splitter inside, and then runs off to various TV points. Pointed at
Sudbury some 35 miles away.
It has worked flawlessly ever since, not even phased by the various
bouts of Freeview channel shifting. Art least, that was until a couple
of days ago. Mother's TV was glitching and dropping out on most
channels. So fearing some woe had befallen the aerial or a co-ax, I got
out Terry, my trusty UHF signal meter, and plugged it into the drop wire >>> from the aerial, turned on the meter's 12V power supply, and low and
behold, six muxes, all at a solid 72 to 84dB, and all showing a "Pass"
quality.
So rejigged to allow the normal PSU to feed the masthead amp and
measured again - same result. Connected the splitter up and looked at
the output. Again a fine display of passes and levels showing 67 - 76
dB. Seemed pretty reasonable after a 5 way split. Then metered the
aerial socket near the TV, again spot on. Plugged it into the TV, glitch >>> city...
Noise getting in? The flylead was a cheap thin premade jobbie. So I made >>> up a nice new one with some WF100 double screened co-ax, and no better.
It was beginning to look like it might actually be a tuner fault on the
TV. Fortunately there was a spare one that I had recently pulled out of
an office prior to a re-furb. So I got that, set it up expecting better
results, and nope, exactly the same symptoms. Too much signal? Added a
6dB attenuator inline - nope that was worse.
I was now entering the clutching at straws phase. Could the amp's PSU be >>> injecting noise (18 year old caps and all that)? So I pulled that out
looked at its output on the DSO - smooth as a baby's bum.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi
access point at the back of the house a few days ago (long way from the
TV), however that also supported mesh operation, so I enabled that, and
then turned on the 5GHz wifi on the main router (previously I had that
turned off since it was tricky to get it to play nice with other 5GHz
access points without a mesh capability). So out of curiosity, I turned
off the 5GHz network on the main router, and tada! Problem sorted.
Odd it could upset two different sets placed about 6m and a couple of
walls away from the router, yet it did not upset the network TV tuner
sat 500mm away from the router (which I only thought to check later!)
Both oldish LG sets, but of different vintage.
The amp is level with the top of the chimney - mounted on the mast near
the lashing kits. So probably straight line distance from the WiFi
aerials is say 6m. However that will be through at least 5 layers of
foil lined plasterboard...
have higher powered 5.8 G links up on our TV aerial with no adverse u
issues it does seem rather odd I'd normally suspect that overloading the
aerial amp and causing intermod ..
I did wonder that at the time when I realised what the cause was (the
amp PSU and the splitter is probably only 1.5m from the wifi source).
However with hindsight I am somewhat sceptical. Partly because the
aerial install is fairly well screened - all dual screen foiled coax, F connectors, metal clad splitter, and the internal construction of the
PSU itself is impressive with the RF elements fully enclosed in a metal screening box. (although obs the aerial itself is not screened!)
However the more conclusive evidence is the fact that the-a TV in our bedroom was still working fine, as was my network connected TV tuner,
and that is in the same comms cabinet as the router (although the wifi aerials are on mag bases on top of the cabinet). Both fed from outputs
on the same splitter. I suspect it is a weakness in the LG tuner design. (the bedroom HiSense is only about 1.5m from the exterior wifi AP, and
that still has 5GHz enabled at about 60% max power). Might be worth experimenting a bit since I can control the maximum wifi output power.
Mind you 35 miles away from that TX is likely to be a weak "ish" input
signal, its not the most powerful one in the country!.
You sure you didn't mean Kilometres or by road?..
http://tx.mb21.co.uk/mapsys/map.php?mapid=95
Yup 35 was an over estimate, I just measured it on google earth - it is
just over 27 miles line of sight to Sudbury. When I installed the system
I was balancing analogue and digital channels at the time, and not all
the digital channels were being transmitted at full power, so used a
decent quality 18 element Yagi and a variable gain amp so I could set a suitable level that would work for all.
Although I note that the local relay station (which only carried the
public service muxes at the time I designed the system), now carries all six, and also operates as a SFN mirroring the Sudbury channels (29, 32,
37, 41, 44, 47). Only 4 kW ERP (compared to Sudbury's 100kW), but it is
only 2 miles away, although 90 degrees off axis for the aerial.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi
access point at the back of the house a few days ago (long way from the
TV), however that also supported mesh operation, so I enabled that, and
then turned on the 5GHz wifi on the main router (previously I had that turned off since it was tricky to get it to play nice with other 5GHz
access points without a mesh capability). So out of curiosity, I turned
off the 5GHz network on the main router, and tada! Problem sorted.
On 23/09/2026 02:34, John Rumm wrote:
On 22/09/2026 23:32, tony sayer wrote:
In article <118usjp$17ta8$1@dont-email.me>, John Rumm <see.my.signature@ >>> nowhere.null> scribeth thus
Well that was a fun exercise...How close to the TV and or aerial amp is this unit can you say?, as we
Some 18 years ago I put up a new aerial (group B with some bits hacked >>>> off on Bill's instructions to tune it to act more like a group E).
Decent Proception masthead amp and power supply, 5 way inductive
splitter inside, and then runs off to various TV points. Pointed at
Sudbury some 35 miles away.
It has worked flawlessly ever since, not even phased by the various
bouts of Freeview channel shifting. Art least, that was until a couple >>>> of days ago. Mother's TV was glitching and dropping out on most
channels. So fearing some woe had befallen the aerial or a co-ax, I got >>>> out Terry, my trusty UHF signal meter, and plugged it into the drop
wire
from the aerial, turned on the meter's 12V power supply, and low and
behold, six muxes, all at a solid 72 to 84dB, and all showing a "Pass" >>>> quality.
So rejigged to allow the normal PSU to feed the masthead amp and
measured again - same result. Connected the splitter up and looked at
the output. Again a fine display of passes and levels showing 67 - 76
dB. Seemed pretty reasonable after a 5 way split. Then metered the
aerial socket near the TV, again spot on. Plugged it into the TV,
glitch
city...
Noise getting in? The flylead was a cheap thin premade jobbie. So I
made
up a nice new one with some WF100 double screened co-ax, and no better. >>>> It was beginning to look like it might actually be a tuner fault on the >>>> TV. Fortunately there was a spare one that I had recently pulled out of >>>> an office prior to a re-furb. So I got that, set it up expecting better >>>> results, and nope, exactly the same symptoms. Too much signal? Added a >>>> 6dB attenuator inline - nope that was worse.
I was now entering the clutching at straws phase. Could the amp's
PSU be
injecting noise (18 year old caps and all that)? So I pulled that out
looked at its output on the DSO - smooth as a baby's bum.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi
access point at the back of the house a few days ago (long way from the >>>> TV), however that also supported mesh operation, so I enabled that, and >>>> then turned on the 5GHz wifi on the main router (previously I had that >>>> turned off since it was tricky to get it to play nice with other 5GHz
access points without a mesh capability). So out of curiosity, I turned >>>> off the 5GHz network on the main router, and tada! Problem sorted.
Odd it could upset two different sets placed about 6m and a couple of
walls away from the router, yet it did not upset the network TV tuner
sat 500mm away from the router (which I only thought to check later!)
Both oldish LG sets, but of different vintage.
The amp is level with the top of the chimney - mounted on the mast
near the lashing kits. So probably straight line distance from the
WiFi aerials is say 6m. However that will be through at least 5 layers
of foil lined plasterboard...
have higher powered 5.8 G links up on our TV aerial with no adverse u
issues it does seem rather odd I'd normally suspect that overloading the >>> aerial amp and causing intermod ..
I did wonder that at the time when I realised what the cause was (the
amp PSU and the splitter is probably only 1.5m from the wifi source).
However with hindsight I am somewhat sceptical. Partly because the
aerial install is fairly well screened - all dual screen foiled coax,
F connectors, metal clad splitter, and the internal construction of
the PSU itself is impressive with the RF elements fully enclosed in a
metal screening box. (although obs the aerial itself is not screened!)
However the more conclusive evidence is the fact that the-a TV in our
bedroom was still working fine, as was my network connected TV tuner,
and that is in the same comms cabinet as the router (although the wifi
aerials are on mag bases on top of the cabinet). Both fed from outputs
on the same splitter. I suspect it is a weakness in the LG tuner
design. (the bedroom HiSense is only about 1.5m from the exterior wifi
AP, and that still has 5GHz enabled at about 60% max power). Might be
worth experimenting a bit since I can control the maximum wifi output
power.
Mind you 35 miles away from that TX is likely to be a weak "ish" input
signal, its not the most powerful one in the country!.
You sure you didn't mean Kilometres or by road?..
http://tx.mb21.co.uk/mapsys/map.php?mapid=95
Yup 35 was an over estimate, I just measured it on google earth - it
is just over 27 miles line of sight to Sudbury. When I installed the
system I was balancing analogue and digital channels at the time, and
not all the digital channels were being transmitted at full power, so
used a decent quality 18 element Yagi and a variable gain amp so I
could set a suitable level that would work for all.
Although I note that the local relay station (which only carried the
public service muxes at the time I designed the system), now carries
all six, and also operates as a SFN mirroring the Sudbury channels
(29, 32, 37, 41, 44, 47). Only 4 kW ERP (compared to Sudbury's 100kW),
but it is only 2 miles away, although 90 degrees off axis for the aerial.
So after all that, it was back to glitchy reception again today on all
but the HD channels. The plot thickens... (still seeing 60+ dB on the
text meter at the end of the co-ax going into the TV)
Yup 35 was an over estimate, I just measured it on google earth - it
is just over 27 miles line of sight to Sudbury. When I installed the
system I was balancing analogue and digital channels at the time, and
not all the digital channels were being transmitted at full power, so
used a decent quality 18 element Yagi and a variable gain amp so I
could set a suitable level that would work for all.
Although I note that the local relay station (which only carried the
public service muxes at the time I designed the system), now carries
all six, and also operates as a SFN mirroring the Sudbury channels
(29, 32, 37, 41, 44, 47). Only 4 kW ERP (compared to Sudbury's
100kW), but it is only 2 miles away, although 90 degrees off axis for
the aerial.
Was it windy?So after all that, it was back to glitchy reception again today on all
but the HD channels. The plot thickens... (still seeing 60+ dB on the
text meter at the end of the co-ax going into the TV)
Unscreened wall plates?
On 23/09/2026 22:05, John Rumm wrote:
On 23/09/2026 02:34, John Rumm wrote:
On 22/09/2026 23:32, tony sayer wrote:
In article <118usjp$17ta8$1@dont-email.me>, John Rumm
<see.my.signature@
nowhere.null> scribeth thus
Well that was a fun exercise...How close to the TV and or aerial amp is this unit can you say?, as we
Some 18 years ago I put up a new aerial (group B with some bits hacked >>>>> off on Bill's instructions to tune it to act more like a group E).
Decent Proception masthead amp and power supply, 5 way inductive
splitter inside, and then runs off to various TV points. Pointed at
Sudbury some 35 miles away.
It has worked flawlessly ever since, not even phased by the various
bouts of Freeview channel shifting. Art least, that was until a couple >>>>> of days ago. Mother's TV was glitching and dropping out on most
channels. So fearing some woe had befallen the aerial or a co-ax, I >>>>> got
out Terry, my trusty UHF signal meter, and plugged it into the drop >>>>> wire
from the aerial, turned on the meter's 12V power supply, and low
and behold, six muxes, all at a solid 72 to 84dB, and all showing a >>>>> "Pass"
quality.
So rejigged to allow the normal PSU to feed the masthead amp and
measured again - same result. Connected the splitter up and looked at >>>>> the output. Again a fine display of passes and levels showing 67 - 76 >>>>> dB. Seemed pretty reasonable after a 5 way split. Then metered the
aerial socket near the TV, again spot on. Plugged it into the TV,
glitch
city...
Noise getting in? The flylead was a cheap thin premade jobbie. So I >>>>> made
up a nice new one with some WF100 double screened co-ax, and no
better.
It was beginning to look like it might actually be a tuner fault on >>>>> the
TV. Fortunately there was a spare one that I had recently pulled
out of
an office prior to a re-furb. So I got that, set it up expecting
better
results, and nope, exactly the same symptoms. Too much signal? Added a >>>>> 6dB attenuator inline - nope that was worse.
I was now entering the clutching at straws phase. Could the amp's
PSU be
injecting noise (18 year old caps and all that)? So I pulled that out >>>>> looked at its output on the DSO - smooth as a baby's bum.
Scratching my head trying to think what has changed in the last few
days? Then it dawned on me that I had finished installing a new wifi >>>>> access point at the back of the house a few days ago (long way from >>>>> the
TV), however that also supported mesh operation, so I enabled that, >>>>> and
then turned on the 5GHz wifi on the main router (previously I had that >>>>> turned off since it was tricky to get it to play nice with other 5GHz >>>>> access points without a mesh capability). So out of curiosity, I
turned
off the 5GHz network on the main router, and tada! Problem sorted.
Odd it could upset two different sets placed about 6m and a couple of >>>>> walls away from the router, yet it did not upset the network TV tuner >>>>> sat 500mm away from the router (which I only thought to check later!) >>>>> Both oldish LG sets, but of different vintage.
The amp is level with the top of the chimney - mounted on the mast
near the lashing kits. So probably straight line distance from the
WiFi aerials is say 6m. However that will be through at least 5
layers of foil lined plasterboard...
have higher powered 5.8 G links up on our TV aerial with no adverse u
issues it does seem rather odd I'd normally suspect that overloading
the
aerial amp and causing intermod ..
I did wonder that at the time when I realised what the cause was (the
amp PSU and the splitter is probably only 1.5m from the wifi source).
However with hindsight I am somewhat sceptical. Partly because the
aerial install is fairly well screened - all dual screen foiled coax,
F connectors, metal clad splitter, and the internal construction of
the PSU itself is impressive with the RF elements fully enclosed in a
metal screening box. (although obs the aerial itself is not screened!)
However the more conclusive evidence is the fact that the-a TV in our
bedroom was still working fine, as was my network connected TV tuner,
and that is in the same comms cabinet as the router (although the
wifi aerials are on mag bases on top of the cabinet). Both fed from
outputs on the same splitter. I suspect it is a weakness in the LG
tuner design. (the bedroom HiSense is only about 1.5m from the
exterior wifi AP, and that still has 5GHz enabled at about 60% max
power). Might be worth experimenting a bit since I can control the
maximum wifi output power.
Mind you 35 miles away from that TX is likely to be a weak "ish" input >>>> signal, its not the most powerful one in the country!.
You sure you didn't mean Kilometres or by road?..
http://tx.mb21.co.uk/mapsys/map.php?mapid=95
Yup 35 was an over estimate, I just measured it on google earth - it
is just over 27 miles line of sight to Sudbury. When I installed the
system I was balancing analogue and digital channels at the time, and
not all the digital channels were being transmitted at full power, so
used a decent quality 18 element Yagi and a variable gain amp so I
could set a suitable level that would work for all.
Although I note that the local relay station (which only carried the
public service muxes at the time I designed the system), now carries
all six, and also operates as a SFN mirroring the Sudbury channels
(29, 32, 37, 41, 44, 47). Only 4 kW ERP (compared to Sudbury's
100kW), but it is only 2 miles away, although 90 degrees off axis for
the aerial.
So after all that, it was back to glitchy reception again today on all
but the HD channels. The plot thickens... (still seeing 60+ dB on the
text meter at the end of the co-ax going into the TV)
Unscreened wall plates?
On 24/09/2026 00:40, alan_m wrote:
Yup 35 was an over estimate, I just measured it on google earth - it
is just over 27 miles line of sight to Sudbury. When I installed the
system I was balancing analogue and digital channels at the time,
and not all the digital channels were being transmitted at full
power, so used a decent quality 18 element Yagi and a variable gain
amp so I could set a suitable level that would work for all.
Although I note that the local relay station (which only carried the
public service muxes at the time I designed the system), now carries
all six, and also operates as a SFN mirroring the Sudbury channels
(29, 32, 37, 41, 44, 47). Only 4 kW ERP (compared to Sudbury's
100kW), but it is only 2 miles away, although 90 degrees off axis
for the aerial.
Odd - I am close to Sudbury. Maybe 34 miles.
Ive got a log periodic in the roof feed a distribution amp.
Mostly its flawless.
Trying to run off Sandy heath which is 35 miles away and the other side
of hills, its very dubious, but the other side of those hills i'ts the preferred transmitter
Was it windy?So after all that, it was back to glitchy reception again today on
all but the HD channels. The plot thickens... (still seeing 60+ dB on
the text meter at the end of the co-ax going into the TV)
High signal level is no guarantee of quality if you are getting multiple *and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses
the terrain in between you and the nearest transmitter
Unscreened wall plates?
QAM is pretty good at dealing with reflections off fixed items - its designed for that. I've generally found that aircraft, waving trees or
long distance tropsheric skip is the major problems
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury transmissions
In the analogue days I could even see the pictures from these transmitters.
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Very little air traffic beyond the odd warbird from Cambridge is ever
over here, so again I don't have problems with that.
I dunno if your TV displays it, but there is often a 'signal quality'
meter of some sort. Sometimes you can use that in conjunction with
changing aerial position to optimise signal levels
I had to change aerials to one better suited to Sudbury digital. I've
got a log periodic in the loft now that works very well.
I could see some variation in signal level on Terry, but even at its
lowest, still well above what I would have expected to be required.
(although worth noting when I was reading 60dB+ at the set back, while
it was glitchy. Adding a 6dB inline attenuator was enough to get the TV
to report "no signal")
It looks like it is a quality rather than quantity issue.
High signal level is no guarantee of quality if you are getting multiple
*and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses
the terrain in between you and the nearest transmitter
I expect there is static multipath since there is a relay about 2 miles
away that runs SFN with Sudbury. Its ERP is only 4kW, and is 90 degrees
off axis, but I would be surprised if some of that is not finding its
way in. (I did not use that Tx originally because at the time it did not >carry all the muxes)
Unscreened wall plates?
QAM is pretty good at dealing with reflections off fixed items - its
designed for that. I've generally found that aircraft, waving trees or
long distance tropsheric skip is the major problems
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury transmissions
In the analogue days I could even see the pictures from these transmitters.
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Very little air traffic beyond the odd warbird from Cambridge is ever
over here, so again I don't have problems with that.
I dunno if your TV displays it, but there is often a 'signal quality'
meter of some sort. Sometimes you can use that in conjunction with
changing aerial position to optimise signal levels
I had to change aerials to one better suited to Sudbury digital. I've
got a log periodic in the loft now that works very well.
Can't say exactly were this was but the channel numbers and hence
frequencies were at the top end of the band 5 and on windy nights the picture would come and go a bit I think in the end they used a satellite
they could see the right bit of sky there, which was fortunate..
As long as the right sort of tiles aren't in use, all aerials ought toVery little air traffic beyond the odd warbird from Cambridge is ever
over here, so again I don't have problems with that.
I dunno if your TV displays it, but there is often a 'signal quality'
meter of some sort. Sometimes you can use that in conjunction with
changing aerial position to optimise signal levels
I had to change aerials to one better suited to Sudbury digital. I've
got a log periodic in the loft now that works very well.
be outside IMHO..
I could see some variation in signal level on Terry, but even at its
lowest, still well above what I would have expected to be required.
(although worth noting when I was reading 60dB+ at the set back, while
it was glitchy. Adding a 6dB inline attenuator was enough to get the TV
to report "no signal")
It looks like it is a quality rather than quantity issue.
Indeed it may well be.
High signal level is no guarantee of quality if you are getting multiple >>> *and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses
the terrain in between you and the nearest transmitter
I expect there is static multipath since there is a relay about 2 miles
away that runs SFN with Sudbury. Its ERP is only 4kW, and is 90 degrees
off axis, but I would be surprised if some of that is not finding its
way in. (I did not use that Tx originally because at the time it did not
carry all the muxes)
Thats interesting. This you might see with a good speccy analyser!.
Unscreened wall plates?
Shouldn't worry about that this problem isn't in the wall plates..
QAM is pretty good at dealing with reflections off fixed items - its
designed for that. I've generally found that aircraft, waving trees or
long distance tropsheric skip is the major problems
Indeed it is ..
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury transmissions >>> In the analogue days I could even see the pictures from these transmitters.
Not surprising where you are Sir, and the bit of ground your on!..
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate
the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
On 25/09/2026 10:29, tony sayer wrote:
I could see some variation in signal level on Terry, but even at its
lowest, still well above what I would have expected to be required.
(although worth noting when I was reading 60dB+ at the set back, while
it was glitchy. Adding a 6dB inline attenuator was enough to get the TV
to report "no signal")
It looks like it is a quality rather than quantity issue.
Indeed it may well be.
High signal level is no guarantee of quality if you are getting multiple >>>> *and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses
the terrain in between you and the nearest transmitter
I expect there is static multipath since there is a relay about 2 miles
away that runs SFN with Sudbury. Its ERP is only 4kW, and is 90 degrees
off axis, but I would be surprised if some of that is not finding its
way in. (I did not use that Tx originally because at the time it did not >>> carry all the muxes)
Thats interesting. This you might see with a good speccy analyser!.
Unscreened wall plates?
Shouldn't worry about that this problem isn't in the wall plates..
QAM is pretty good at dealing with reflections off fixed items - its
designed for that. I've generally found that aircraft, waving trees or >>>> long distance tropsheric skip is the major problems
Indeed it is ..
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury transmissions >>>> In the analogue days I could even see the pictures from these transmitters.
Not surprising where you are Sir, and the bit of ground your on!..
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate
the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it
performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
Indeed, helped a mate sort his aerial. In theory, not a difficult
location. Stuck a decent log periodic up near the apex of his gable
wall. No need for any extra gain. However the signal was very variable
until we also set about a row of trees on the path just outside his garden!
In my case I would not rule out trees, although it seems odd that it
strikes at the time of year where they are losing leaves and general "lushness".
On 25/09/2026 10:29, tony sayer wrote:
I could see some variation in signal level on Terry, but even at its
lowest, still well above what I would have expected to be required.
(although worth noting when I was reading 60dB+ at the set back, while
it was glitchy. Adding a 6dB inline attenuator was enough to get the TV
to report "no signal")
It looks like it is a quality rather than quantity issue.
Indeed it may well be.
High signal level is no guarantee of quality if you are getting
multiple
*and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses
the terrain in between you and the nearest transmitter
I expect there is static multipath since there is a relay about 2 miles
away that runs SFN with Sudbury. Its ERP is only 4kW, and is 90 degrees
off axis, but I would be surprised if some of that is not finding its
way in. (I did not use that Tx originally because at the time it did not >>> carry all the muxes)
Thats interesting. This you might see with a good speccy analyser!.
Unscreened wall plates?
Shouldn't worry about that this problem isn't in the wall plates..
QAM is pretty good at dealing with reflections off fixed items - its
designed for that. I've generally found that aircraft, waving trees or >>>> long distance tropsheric skip is the major problems
Indeed it is ..
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury
transmissions
In the analogue days I could even see the pictures from these
transmitters.
Not surprising where you are Sir, and the bit of ground your on!..
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate
the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it
performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
Indeed, helped a mate sort his aerial. In theory, not a difficult
location. Stuck a decent log periodic up near the apex of his gable
wall. No need for any extra gain. However the signal was very variable
until we also set about a row of trees on the path just outside his garden!
In my case I would not rule out trees, although it seems odd that it
strikes at the time of year where they are losing leaves and general "lushness".
On 25/09/2026 15:21, John Rumm wrote:
On 25/09/2026 10:29, tony sayer wrote:
I could see some variation in signal level on Terry, but even at its
lowest, still well above what I would have expected to be required.
(although worth noting when I was reading 60dB+ at the set back, while >>>> it was glitchy. Adding a 6dB inline attenuator was enough to get the TV >>>> to report "no signal")
It looks like it is a quality rather than quantity issue.
Indeed it may well be.
High signal level is no guarantee of quality if you are getting
multiple
*and varying* multipath reflections.
Oh there is somewhere a website that takes your postcode and analyses >>>>> the terrain in between you and the nearest transmitter
I expect there is static multipath since there is a relay about 2 miles >>>> away that runs SFN with Sudbury. Its ERP is only 4kW, and is 90 degrees >>>> off axis, but I would be surprised if some of that is not finding its
way in. (I did not use that Tx originally because at the time it did
not
carry all the muxes)
Thats interesting. This you might see with a good speccy analyser!.
Unscreened wall plates?
Shouldn't worry about that this problem isn't in the wall plates..
QAM is pretty good at dealing with reflections off fixed items - its >>>>> designed for that. I've generally found that aircraft, waving trees or >>>>> long distance tropsheric skip is the major problems
Indeed it is ..
I,e, there are Dutch transmitters directly 'behind' Sudbury from my
location and in very cold weather I get breakup on Sudbury
transmissions
In the analogue days I could even see the pictures from these
transmitters.
Not surprising where you are Sir, and the bit of ground your on!..
I have no trees in line of sight for at least 300 meters, but other
people in this area who do have some issues. Even with good signal
strength,
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate >>> the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it
performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
Indeed, helped a mate sort his aerial. In theory, not a difficult
location. Stuck a decent log periodic up near the apex of his gable
wall. No need for any extra gain. However the signal was very variable
until we also set about a row of trees on the path just outside his
garden!
In my case I would not rule out trees, although it seems odd that it
strikes at the time of year where they are losing leaves and general
"lushness".
It's been a very dry summer.-a Perhaps the problem became evident once enough water could get up into those leaves.
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate >>> the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it
performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
Indeed, helped a mate sort his aerial. In theory, not a difficult
location. Stuck a decent log periodic up near the apex of his gable
wall. No need for any extra gain. However the signal was very variable
until we also set about a row of trees on the path just outside his garden! >>
In my case I would not rule out trees, although it seems odd that it
strikes at the time of year where they are losing leaves and general
"lushness".
It's been a very dry summer. Perhaps the problem became evident once
enough water could get up into those leaves.
Trees can be more bother than you would think ..
Many years ago we had to fix up a TV in a bit of a wooded country estate >>>> the aerial rigger had dome his bit TV delivered and no channels would
work apart from a bit something waving around in the on screen noise.
In those days hand held level meters weren't yet invented, rigger was
certain that the TV was dud. Telly went back to the workshop where it
performed fine. So another TV was sent out and .. Exactly the same.
In the end 3 off 20 foot poles and joiners and stay wires were rigged
and a stack of two Jaybeam 24 or maybe 48 element aerials and a very
good masthead amp the best co-ax we had at the time was in use and we
just about got a usable almost noise free picture!.
Indeed, helped a mate sort his aerial. In theory, not a difficult
location. Stuck a decent log periodic up near the apex of his gable
wall. No need for any extra gain. However the signal was very variable
until we also set about a row of trees on the path just outside his garden! >>>
In my case I would not rule out trees, although it seems odd that it
strikes at the time of year where they are losing leaves and general
"lushness".
It's been a very dry summer. Perhaps the problem became evident once
enough water could get up into those leaves.
Sometimes, theres an airspaced co-ax cable that can fill up with
water;!..
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