Home Theatre picking up signals?

[nick]

Not from aliens but from CB type communications Im assuming. I have a Sansui 5.1 home theatre system I use for my HTPC, nothing fancy but gets the job done. Every now and then it'll be on and a very distorted low voice will start coming out of all the speakers..  First time I heard it and then tried to explain it to the girlfriend she thought I was nuts but now it does it quite regularly. Its definately someone talking, I cant make out a single word as its too distorted but its a conversation between people. The guy about 3 houses down from me has this HUGE antenna thing in his front yard and I blame him 

Any idea on how to get rid of it? I was thinking of buying one of those frequency scanner things and attempting to hear what they are saying.

[Andrew]

I'd lend you my tinfoil hat, but I need it.    That really sounds weird. When do you get it - I assume while watching TV? Antenna-based TV or DStv?

[Macross]

Time to have the house blessed.

[nick]

The TV (Plasma) is mostly used for watching movies from my HTPC which is connected via VGA cable to the TV and a normal 3.5" Stereo to two RCA's into the Sansui active sub (which all the speakers then connect to). If the HTPC and home theatre system is on it'll just randomly happen in the evenings. Doesnt do it (that Ive noticed) with my stereo setup which is a few cm away from all of this equipment...

[LAV]

These things can be VERY tricky to solve.

The answer is one that you might not want to hear. With cheaper equipment shortcuts are often taken, so screening and proper design for immunity against radio frequency interference takes a back seat.

There are ways to minimise this. Keep all input wiring as short as possible. Make sure all earthing and earth connections are good. That would include any cabling connected to any part of the system. On TV antenna systems, any bad/corroded connection could act as a detector for strong RF signals.

You could also try clip-on ferrite cores and thread a loop or two of the cable from the PC through one before it enters the Sansui.

[nick]

These things can be VERY tricky to solve.

The answer is one that you might not want to hear. With cheaper equipment shortcuts are often taken, so screening and proper design for immunity against radio frequency interference takes a back seat.

There are ways to minimise this. Keep all input wiring as short as possible. Make sure all earthing and earth connections are good. That would include any cabling connected to any part of the system. On TV antenna systems, any bad/corroded connection could act as a detector for strong RF signals.

You could also try clip-on ferrite cores and thread a loop or two of the cable from the PC through one before it enters the Sansui.

Next time it happens I'll try unplug input cables and see if it disapears. Currently connected to system is my TV (via RCA), DVD player via component cables (front left, front right, sub etc) the HTPC via RCA and the xbox via RCA.

[LAV]

Lots of cables, and they could all potentially be the source. Unplug them at the Sansui end though, as any long cables left plugged in and open on the other end also make great antennas.

[Ampdog]

The 'huge antenna thing' of the guy-3-houses-down; what exactly is it? A dish? Yagi or other multi-elemented and aimed at you? Was it erected/changed just before your problems started?

If he is a radio ham, he would probably be interested in learning that interference is caused. They are usually very helpful - have a code of conduct to adhere to. Otherwise as mentioned by others above.

[LAV]

If he is a radio ham, he would probably be interested in learning that interference is caused. They are usually very helpful - have a code of conduct to adhere to.

Agreed.

[nick]

The 'huge antenna thing' of the guy-3-houses-down; what exactly is it? A dish? Yagi or other multi-elemented and aimed at you? Was it erected/changed just before your problems started?

If he is a radio ham, he would probably be interested in learning that interference is caused. They are usually very helpful - have a code of conduct to adhere to. Otherwise as mentioned by others above.

This sort of thing just bigger

[surfsup]

This sort of thing just bigger

I can tell you it is definatley RF cutting through on your system. He is probably transmitting on SSB (single side band) which is renowned for spurious RF cutting into everything. You can even light up light bulbs with the RF from those things just by standing next to the antenna or RF cable feeding the antenna with the light bulb in your hand.

As the previous post said, try chatting to the guy and ask if there is anything he can do to "tone" it down a bit. Then earth everything best you can and some ferrite cores might help as well. GOOD LUCK!

P.S. Transmit properties of SSB are very much effected by weather, so it might appear worse on certain days, just depending.

[nick]

Havent really used the Sansui system for a while but was watching a movie with the SO (and its raining..  ) and the weird person was talking to me on my system again. Unplugged all inputs, xbox, tv, HTPC etc made no difference. No difference switching between CD/DVD/AUX etc on the system. I see yebo has a radio you can build as project that can receive SW. Might grab one and see if I can hear what they are saying as it doesnt sound like English..

[windshear]

. You can even light up light bulbs with the RF from those things just by standing next to the antenna or RF cable feeding the antenna with the light bulb in your hand.

Also cause blood clots etc, i remember as a radio appy making flourescent bulbs glow with rf coils and adhering to the warning labels associated with the kits !

[Steerpike]

I see yebo has a radio you can build as project that can receive SW. Might grab one and see if I can hear what they are saying as it doesnt sound like English..

You can't receive SSB transmissions on an ordinary shortwave radio. You've got to have a carrier-regeneration oscillator, which isn't in most 'commercial' receivers.

[Ampdog]

Nick,

Still trying to help. Presuming you can see this antenna thingy from your house, can you possibly take a photo (not too telephoto) from your house and post it here? Those of us fimiliar with this sort of thing might then be better able to advise .