Electrical circuit noise filters?

JerryMungo

JerryMungo

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Probably not the right forum, but here goes...

Is there anything that I can stick on my power line just before the HDMI switch I use to prevent noisy electronic gadgets from occasionally disrupting the HDMI signal? Whenever my tumble drier changes it's cycle ans turns the heater / motor on or off the screen goes blank for a second. Really annoying.
 
Drying your hears and surfing net simultenously? ;)

Not, but you can do couple things:

- using mains filters on each equipment, starting from tumble drier
- powering tumble drier from another mains outlet
- powering PC and screen from the same mains outlet
- using quality schielded and short HDMI cables (not longer than neccessary)

Hope it helps. :)
 
Replace the tumble drier?
Look for an active line filter or use a better PSU for the HDMI switch.
 
sajunky said:
Drying your hears and surfing net simultenously? ;)

Not, but you can do couple things:

- using mains filters on each equipment, starting from tumble drier
- powering tumble drier from another mains outlet- powering PC and screen from the same mains outlet
- using quality schielded and short HDMI cables (not longer than neccessary)

Hope it helps. :)
Click to expand...

Could be a power surge rather than noise --- hence why the bold option is important. Next make sure the switch , the TVs connected to it and any other devices all get their power from the same DB board socket circuit. Use a UPS to feed these units with power and not just plugged into the mains.
 
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Uh, I'm worried about the fact that there is any interference at all - sounds to me like a dodgy PSU in your desktop not regulating voltages properly.

This assumes of course you are using a desktop plugged into the TV. Is your setup something different like a laptop or HTPC plugged into the TV?
 
A normal cheapy UPS will not help!!!
You would have to get a on-line or double conversion unit, which does not come cheap.
 
That sounds like an earthing issue to me and definitely isn't normal.
 
SauRoNZA said:
That sounds like an earthing issue to me and definitely isn't normal.
Click to expand...

Could be certainly.

Recently saw some very strange issues that we traced to a poor earth on a complete power circuit. Ironically, what had transpired was a home changed hands. The CoC process identified an overloaded plug circuit which required some power sockets to be moved onto a new circuit on a separate breaker. The new circuit was installed but the earth was never connected to the common earth in the DB board. ........ Yet the owner produced a signed off CoC ! Makes one think does it not. The system went from a slightly overloaded circuit with proper earthing to an even more dangerous situation.
 
Geoff.D said:
Could be a power surge rather than noise --- hence why the bold option is important. Next make sure the switch , the TVs connected to it and any other devices all get their power from the same DB board socket circuit. Use a UPS to feed these units with power and not just plugged into the mains.
Click to expand...
Tumble drier heater and motor, as with most heating appliances and AC motors will be almost a dead short when it kicks in. That said, no doubt the motor may be drawing more than it should and perhaps the condenser is not functioning 100%. Possibly creating induction noise.
https://www.dslreports.com/forum/r29387296-Powerline-AV-not-affected-by-fans-but-a-vacuum-cleaner

agentrfr said:
Uh, I'm worried about the fact that there is any interference at all - sounds to me like a dodgy PSU in your desktop not regulating voltages properly.

This assumes of course you are using a desktop plugged into the TV. Is your setup something different like a laptop or HTPC plugged into the TV?
Click to expand...
It's not a desktop - I have DSTV, Wii U and Raspberry Pi plugged into a 4x2 HDMI switch that outputs to two TVs. It's only the HDMI switch that's sensitive to these issues. No flickering whatsoever when connected directly to the TV/s.

Some line noise is quite normal but I also suspect a bit of noise around the hdmi switch through multiple gadgets creating multiple ground paths via HDMI cables. Perhaps a combination of that and the tumble drier motor. I may try eliminating ground from all but one of the HDMI cables to see if I can sort it.
 
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10 internet points says you're using a under spec'd cell charger to drive your rasp.
 
Heavyonthemagick said:
Tumble drier heater and motor, as with most heating appliances and AC motors will be almost a dead short when it kicks in. That said, no doubt the motor may be drawing more than it should and perhaps the condenser is not functioning 100%. Possibly creating induction noise.
https://www.dslreports.com/forum/r29387296-Powerline-AV-not-affected-by-fans-but-a-vacuum-cleaner

It's not a desktop - I have DSTV, Wii U and Raspberry Pi plugged into a 4x2 HDMI switch that outputs to two TVs. It's only the HDMI switch that's sensitive to these issues. No flickering whatsoever when connected directly to the TV/s.

Some line noise is quite normal but I also suspect a bit of noise around the hdmi switch through multiple gadgets creating multiple ground paths via HDMI cables. Perhaps a combination of that and the tumble drier motor. I may try eliminating ground from all but one of the HDMI cables to see if I can sort it.
Click to expand...

Ferrite beads on the HDMI cable maybe?

Should only need it on the final cable going into the TV, but if you can trace the source that might also help.
 
Heavyonthemagick said:
Tumble drier heater and motor, as with most heating appliances and AC motors will be almost a dead short when it kicks in. That said, no doubt the motor may be drawing more than it should and perhaps the condenser is not functioning 100%. Possibly creating induction noise.
https://www.dslreports.com/forum/r29387296-Powerline-AV-not-affected-by-fans-but-a-vacuum-cleaner

It's not a desktop - I have DSTV, Wii U and Raspberry Pi plugged into a 4x2 HDMI switch that outputs to two TVs. It's only the HDMI switch that's sensitive to these issues. No flickering whatsoever when connected directly to the TV/s.

Some line noise is quite normal but I also suspect a bit of noise around the hdmi switch through multiple gadgets creating multiple ground paths via HDMI cables. Perhaps a combination of that and the tumble drier motor. I may try eliminating ground from all but one of the HDMI cables to see if I can sort it.
Click to expand...

In that case how about trying a bigger power supply for the HDMI comber?
 
Heavyonthemagick said:
Tumble drier heater and motor, as with most heating appliances and AC motors will be almost a dead short when it kicks in. That said, no doubt the motor may be drawing more than it should and perhaps the condenser is not functioning 100%. Possibly creating induction noise.
https://www.dslreports.com/forum/r29387296-Powerline-AV-not-affected-by-fans-but-a-vacuum-cleaner

It's not a desktop - I have DSTV, Wii U and Raspberry Pi plugged into a 4x2 HDMI switch that outputs to two TVs. It's only the HDMI switch that's sensitive to these issues. No flickering whatsoever when connected directly to the TV/s.

Some line noise is quite normal but I also suspect a bit of noise around the hdmi switch through multiple gadgets creating multiple ground paths via HDMI cables. Perhaps a combination of that and the tumble drier motor. I may try eliminating ground from all but one of the HDMI cables to see if I can sort it.
Click to expand...

Keep us posted on what works and what does not please.

You should not have to resort to fiddling with the cables. Makes for complexity in the future.

Where is the HDMI switch installed? at some or other central point or close to the majority of the sources of HDMI content?
 
SauRoNZA said:
Ferrite beads on the HDMI cable maybe?

Should only need it on the final cable going into the TV, but if you can trace the source that might also help.
Click to expand...
I think the issue is the on-board digital processing in the HDMI switch. I'm guessing the developers didn't think the grounding through.

agentrfr said:
In that case how about trying a bigger power supply for the HDMI comber?
Click to expand...
Not sure how that would help. I don't think it's losing current. Unless of course the design of the PSU or board didn't take into account sufficient capacitors.

Geoff.D said:
Keep us posted on what works and what does not please.

You should not have to resort to fiddling with the cables. Makes for complexity in the future.

Where is the HDMI switch installed? at some or other central point or close to the majority of the sources of HDMI content?
Click to expand...

I agree - though if this is a grounding issue with the HDMI box, I may just need a closer look at the design. With potentially 6 gadgets attached, two of which are earthed, this may actually just be a bit of a ground noise mess. In the old days it was as easy as identifying hum on your analogue audio equipment when something turns on lol... not so easy anymore. I'll keep everyone posted.
 
Heavyonthemagick said:
.....

I agree - though if this is a grounding issue with the HDMI box, I may just need a closer look at the design. With potentially 6 gadgets attached, two of which are earthed, this may actually just be a bit of a ground noise mess. In the old days it was as easy as identifying hum on your analogue audio equipment when something turns on lol... not so easy anymore. I'll keep everyone posted.
Click to expand...

Ja it has got quite complicated to find and isolate a grounding issue!

Reminds me of the 110 Volts that appears on the chassis of DSTV decoders .....
 
Heavyonthemagick said:
It's not a desktop - I have DSTV, Wii U and Raspberry Pi plugged into a 4x2 HDMI switch that outputs to two TVs. It's only the HDMI switch that's sensitive to these issues. No flickering whatsoever when connected directly to the TV/s.

Some line noise is quite normal but I also suspect a bit of noise around the hdmi switch through multiple gadgets creating multiple ground paths via HDMI cables. Perhaps a combination of that and the tumble drier motor. I may try eliminating ground from all but one of the HDMI cables to see if I can sort it.
Click to expand...
^This. And perhaps some of devices are powered on from different mains socket. Use a multiple plug extension to get maximum number of devices powered from the same place. I still advice to try different HDMI cables. There are ferrite modules you can clamp on the cable. It will limit high frequency rush current. Get it from places like Communica. However low frequency multipath current such like from heaters and electric motors is difficult to get rid of. If you ignore it, wait and see what the first lightning storm can bring in...
 
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^^They're all on the same circuit. That said, almost all homes have a single circuit, not? The separate lines from your DB all converge at the mains inlet via circuit breakers, so while you can isolate circuits, while everything is normal, there is only one circuit effectively... or multiple parallel segments of a single circuit, or am I mistaken?

I have some of those cables, though the cable to my TV is not one, I may just replace that with a ferrite magnet based one. As for lightning... spot on I have just recently replaced the Pi and Switch for that reason :)
 
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