We have a triple light switch by the door- 1 switches on the 2 outside lights and the other 2 are for internal lights. All lights have LED globes. But last night when we turned on the outside lights we lost the TV reception as did the 5th wheeler next door. Tried it again tonight and it happens every time the outside lights are switched on - turn the light off and TV reception returns.
This has never happened before - anybody got any clues please
blaze said
09:38 PM Dec 8, 2018
led globes causing interference
cheers
blaze
villatranquilla said
09:47 PM Dec 8, 2018
blaze wrote:
led globes causing interference cheers blaze
but its been Ok for a couple of years - nothing has been changed so is this likely
aussie_paul said
09:52 PM Dec 8, 2018
Bad earth?
Aussie Paul.
kgarnett said
02:50 PM Dec 9, 2018
When you say it has been OK for a couple of years, were you parked in the same location with same antenna orientation as you are now.
If you are in a different location the tv signal from the transmitter may be low so that the radiated interference from the LEDs may overwhelm the TV signal.
In a higher TV signal location the LED interference may be less of a problem.
Ken
iana said
04:36 PM Dec 9, 2018
We have exactly the same problem, the two outside lights turn off the TV, no other lights effect the TV. Just haven't had the time to check it out.
oldtrack123 said
07:15 PM Dec 9, 2018
Pretty obvious that it is a radiated interference problem from the leds with a weak tv signal. try repositioning /redirecting the tv areal ,if possible .
Mike Harding said
08:31 PM Dec 9, 2018
oldtrack123 wrote:
Pretty obvious that it is a radiated interference problem from the leds with a weak tv signal. try repositioning /redirecting the tv areal ,if possible .
Why do you suggest it's radiated rather than conducted?
oldtrack123 said
09:31 PM Dec 9, 2018
Mike Harding wrote:
oldtrack123 wrote:
Pretty obvious that it is a radiated interference problem from the leds with a weak tv signal. try repositioning /redirecting the tv areal ,if possible .
Why do you suggest it's radiated rather than conducted?
From this" as did the fifth wheeller next door"
Unlikely that it would be line conducted interference all that way back through the 240V wiring
villatranquilla said
09:57 PM Dec 9, 2018
kgarnett wrote:
When you say it has been OK for a couple of years, were you parked in the same location with same antenna orientation as you are now.
If you are in a different location the tv signal from the transmitter may be low so that the radiated interference from the LEDs may overwhelm the TV signal. In a higher TV signal location the LED interference may be less of a problem.
Ken
hopefully this is the answer. The TV reception was poor in this location when we set up on Friday. Will try it out when we get home tomorrow as we have not had problems when parked at home.
Mike Harding said
12:08 PM Dec 10, 2018
oldtrack123 wrote:
Mike Harding wrote:
oldtrack123 wrote:
Pretty obvious that it is a radiated interference problem from the leds with a weak tv signal. try repositioning /redirecting the tv areal ,if possible .
Why do you suggest it's radiated rather than conducted?
From this" as did the fifth wheeller next door"
Unlikely that it would be line conducted interference all that way back through the 240V wiring
It's quite likely it would.
villatranquilla said
02:10 PM Dec 10, 2018
seems as though Ken (kgarnett) was on the money. Tried it all at home today and all is working perfectly - no interference at all.
Thanks Ken
PeterD said
03:33 PM Dec 10, 2018
villatranquilla wrote:
We have a triple light switch by the door- 1 switches on the 2 outside lights and the other 2 are for internal lights. All lights have LED globes. But last night when we turned on the outside lights we lost the TV reception as did the 5th wheeler next door. Tried it again tonight and it happens every time the outside lights are switched on - turn the light off and TV reception returns.
This has never happened before - anybody got any clues please
If it is affecting the van next door it certainly NOT conducted.
You did not say if you lost all the channels or just the one you prefer to watch. Where were you at the time and what channels were affected?
The switched regulator in the globes is likely to produce a range of rough signals and not necessarily an across the spectrum white noise. It is possible you have not been in areas where the current channels being affected now were being used.
Do you have a spare globe you can swap for the one in use? If so give it a try, the replacement may interfere with different frequency signals. If so you may have to swap the globes as you travel if you can not find a quiet one.
Mike Harding said
04:32 PM Dec 10, 2018
PeterD wrote: If it is affecting the van next door it certainly NOT conducted.
Perhaps you will provide a technical rationale for your certainty?
PeterD said
06:35 PM Dec 10, 2018
Mike Harding wrote:
PeterD wrote: If it is affecting the van next door it certainly NOT conducted.
Perhaps you will provide a technical rationale for your certainty?
Perhaps you could explain how interference in a 12 V system in one van can conduct to the next van. It will not conduct back past the battery and battery charger.
markf said
06:56 PM Dec 10, 2018
PeterD wrote:
Mike Harding wrote:
PeterD wrote: If it is affecting the van next door it certainly NOT conducted.
Perhaps you will provide a technical rationale for your certainty?
Perhaps you could explain how interference in a 12 V system in one van can conduct to the next van. It will not conduct back past the battery and battery charger.
Via the caravan parks earthing system is only one possible route.
Conducted interference can follow amazingly convoluted and seemingly isolated routes.
PeterD said
07:01 PM Dec 10, 2018
markf wrote:
PeterD wrote:
Mike Harding wrote:
PeterD wrote: If it is affecting the van next door it certainly NOT conducted.
Perhaps you will provide a technical rationale for your certainty?
Perhaps you could explain how interference in a 12 V system in one van can conduct to the next van. It will not conduct back past the battery and battery charger.
Via the caravan parks earthing system is only one possible route.
Conducted interference can follow amazingly convoluted and seemingly isolated routes.
It may conduct that far at audio or AM radio frequencies but not TV frequencies.
Mike Harding said
07:04 PM Dec 10, 2018
PeterD wrote:
Mike Harding wrote:
PeterD wrote: If it is affecting the van next door it certainly NOT conducted.
Perhaps you will provide a technical rationale for your certainty?
Perhaps you could explain how interference in a 12 V system in one van can conduct to the next van. It will not conduct back past the battery and battery charger.
I certainly will.
We are discussing frequencies in the hundreds of megahertz region and they do not behave in the same way as the low frequencies you may be more familiar with. Parasitic effects have a far greater impact at such frequencies and a battery simply looks like a capacitor with built in transmission lines at 200MHz or the like.
For the past 25+ years I have been designing electronics systems which are required to comply with both emissions and immunity EMC standards and for the past six years I have specialised in EMC consulting and if I have learned nothing else over that time I have learned never to say "It can't do that" with EMC it's is far, far too complicated in its behaviour and will find coupling paths you never dreamt of.
In this case I suspect the issue was radiated but *never* assume with EMC.
oldtrack123 said
04:35 PM Dec 11, 2018
Mike Harding wrote:
I certainly will.
We are discussing frequencies in the hundreds of megahertz region and they do not behave in the same way as the low frequencies you may be more familiar with. Parasitic effects have a far greater impact at such frequencies and a battery simply looks like a capacitor with built in transmission lines at 200MHz or the like.
For the past 25+ years I have been designing electronics systems which are required to comply with both emissions and immunity EMC standards and for the past six years I have specialised in EMC consulting and if I have learned nothing else over that time I have learned never to say "It can't do that" with EMC it's is far, far too complicated in its behaviour and will find coupling paths you never dreamt of.
In this case I suspect the issue was radiated but *never* assume with EMC.
And what:
[a]does a capacitor do very well@ very high frequencies?
what does any inductance even self inductance in the cable do at very high frequencies?? especially any form of coil or iron ......Are you suggesting that such could get back through a long run of cable two battery chargers & @ least two batteries all of which would either act as chokes or bypass capacitors
-- Edited by oldtrack123 on Tuesday 11th of December 2018 04:45:54 PM
Whenarewethere said
05:12 PM Dec 11, 2018
I once had a switch affecting an AM radio. It turned out to be build up of carbon from arcing in the switch which gave a slightly poor contact. I was a really old light switch. Got in a new switch & the problem was fixed.
Mike Harding said
05:26 PM Dec 11, 2018
oldtrack123 wrote:
Mike Harding wrote:
I certainly will.
We are discussing frequencies in the hundreds of megahertz region and they do not behave in the same way as the low frequencies you may be more familiar with. Parasitic effects have a far greater impact at such frequencies and a battery simply looks like a capacitor with built in transmission lines at 200MHz or the like.
For the past 25+ years I have been designing electronics systems which are required to comply with both emissions and immunity EMC standards and for the past six years I have specialised in EMC consulting and if I have learned nothing else over that time I have learned never to say "It can't do that" with EMC it's is far, far too complicated in its behaviour and will find coupling paths you never dreamt of.
In this case I suspect the issue was radiated but *never* assume with EMC.
And what:
[a]does a capacitor do very well@ very high frequencies?
what does any inductance even self inductance in the cable do at very high frequencies?? especially any form of coil or iron ......Are you suggesting that such could get back through a long run of cable two battery chargers & @ least two batteries all of which would either act as chokes or bypass capacitors
Oh Gawd! Don't tell me you're an expert on EMC too (a PhD perhaps?) in addition to all your other wisdom.
When you're at the bottom of the hole... stop digging.
oldtrack123 said
06:17 PM Dec 11, 2018
Mike Harding wrote:
oldtrack123 wrote:
Mike Harding wrote:
I certainly will.
We are discussing frequencies in the hundreds of megahertz region and they do not behave in the same way as the low frequencies you may be more familiar with. Parasitic effects have a far greater impact at such frequencies and a battery simply looks like a capacitor with built in transmission lines at 200MHz or the like.
For the past 25+ years I have been designing electronics systems which are required to comply with both emissions and immunity EMC standards and for the past six years I have specialised in EMC consulting and if I have learned nothing else over that time I have learned never to say "It can't do that" with EMC it's is far, far too complicated in its behaviour and will find coupling paths you never dreamt of.
In this case I suspect the issue was radiated but *never* assume with EMC.
And what:
[a]does a capacitor do very well@ very high frequencies?
what does any inductance even self inductance in the cable do at very high frequencies?? especially any form of coil or iron ......Are you suggesting that such could get back through a long run of cable two battery chargers & @ least two batteries all of which would either act as chokes or bypass capacitors
Oh Gawd! Don't tell me you're an expert on EMC too (a PhD perhaps?) in addition to all your other wisdom.
When you're at the bottom of the hole... stop digging.
Not a very good answer or is it you simply cannot answer???
We have a triple light switch by the door- 1 switches on the 2 outside lights and the other 2 are for internal lights. All lights have LED globes. But last night when we turned on the outside lights we lost the TV reception as did the 5th wheeler next door. Tried it again tonight and it happens every time the outside lights are switched on - turn the light off and TV reception returns.
This has never happened before - anybody got any clues please
cheers
blaze
but its been Ok for a couple of years - nothing has been changed so is this likely
Bad earth?
Aussie Paul.
If you are in a different location the tv signal from the transmitter may be low so that the radiated interference from the LEDs may overwhelm the TV signal.
In a higher TV signal location the LED interference may be less of a problem.
Ken
Pretty obvious that it is a radiated interference problem from the leds with a weak tv signal. try repositioning /redirecting the tv areal ,if possible .
Why do you suggest it's radiated rather than conducted?
From this" as did the fifth wheeller next door"
Unlikely that it would be line conducted interference all that way back through the 240V wiring
hopefully this is the answer. The TV reception was poor in this location when we set up on Friday. Will try it out when we get home tomorrow as we have not had problems when parked at home.
It's quite likely it would.
Thanks Ken
If it is affecting the van next door it certainly NOT conducted.
You did not say if you lost all the channels or just the one you prefer to watch. Where were you at the time and what channels were affected?
The switched regulator in the globes is likely to produce a range of rough signals and not necessarily an across the spectrum white noise. It is possible you have not been in areas where the current channels being affected now were being used.
Do you have a spare globe you can swap for the one in use? If so give it a try, the replacement may interfere with different frequency signals. If so you may have to swap the globes as you travel if you can not find a quiet one.
Perhaps you will provide a technical rationale for your certainty?
Perhaps you could explain how interference in a 12 V system in one van can conduct to the next van. It will not conduct back past the battery and battery charger.
Via the caravan parks earthing system is only one possible route.
Conducted interference can follow amazingly convoluted and seemingly isolated routes.
It may conduct that far at audio or AM radio frequencies but not TV frequencies.
I certainly will.
We are discussing frequencies in the hundreds of megahertz region and they do not behave in the same way as the low frequencies you may be more familiar with. Parasitic effects have a far greater impact at such frequencies and a battery simply looks like a capacitor with built in transmission lines at 200MHz or the like.
For the past 25+ years I have been designing electronics systems which are required to comply with both emissions and immunity EMC standards and for the past six years I have specialised in EMC consulting and if I have learned nothing else over that time I have learned never to say "It can't do that" with EMC it's is far, far too complicated in its behaviour and will find coupling paths you never dreamt of.
In this case I suspect the issue was radiated but *never* assume with EMC.
And what:
[a]does a capacitor do very well@ very high frequencies?
what does any inductance even self inductance in the cable do at very high frequencies?? especially any form of coil or iron ......Are you suggesting that such could get back through a long run of cable two battery chargers & @ least two batteries all of which would either act as chokes or bypass capacitors
-- Edited by oldtrack123 on Tuesday 11th of December 2018 04:45:54 PM
I once had a switch affecting an AM radio. It turned out to be build up of carbon from arcing in the switch which gave a slightly poor contact. I was a really old light switch. Got in a new switch & the problem was fixed.
Oh Gawd! Don't tell me you're an expert on EMC too (a PhD perhaps?) in addition to all your other wisdom.
When you're at the bottom of the hole... stop digging.
Not a very good answer or is it you simply cannot answer???