BIG PROBLEM..radio signal during sermon and worship

[[Admin] osborn4]

Awesome. I love simple solutions.

[waynehoskins]

Could also be SWBC. I think we have some of those stateside still.

Since it affects some loudspeaker systems more than others, and we're pretty sure it's coming in the speaker leads, you could also make note of the lengths of speaker cable involved where the signal is strongest; this might be close to a quarter wavelength on their transmitting frequency -- but since it's showing up everywhere at different amplitudes, I have my doubts that you actually have a magic 1/4WL speaker lead, possibly closer to it, but you probably won't be able to translate that directly to the frequency.

However, that might help narrow down what kind of station it is. Do you have approximate speaker cable lengths for where it's strongest and one where it's weaker?

[cmchamp]

If you happen to be in the saturation zone, there may be nothing that can help.
I have a client in the saturation zone (less than 1/2 mile) and I've checked speaker cable length, all the 'regular' solutions and irregular. This church is a late 1800's church with multiple earth grounds and a gold leafed organ loft.
My unorthodox solution . . . . I have 1 mic line from the chancel that has the local AM/FM station on it. As long as I keep it plugged in to a mic input with the channel muted, no RFI interference occurs anywhere else in the system. When I disconnect that RFI impregnated line, RFI saturates the entire system.
They're a traditional church, so loosing 1 channel to keep the RFI out isn't a big sacrifice.
C.

[avsoundguy]

well we checked all cable is shielded cable, and we were listenin and its a korean station so what im gonna do is figure out wat station it is and try to contact them. and also we added length to our speaker cable and it was still the same..and now i figured out another problem during worship practice..my condenser mics give off radio signal as well why is that..
and thanks to everyone that replied u are all very helpful!!

[pdc]

You can check that your cable is a "shielded" type, but you have no assurance that the shielding is 100% throughout the run. There is also a difference between a shield and a ground.

Assuming that all of your gear is balanced (properly), I would also rewire the whole place with balanced Star Quad cable. This will offer superior rejection of RF, EMF, noise, etc.

RF can come in anywhere. However, condenser mics are typically not suspect.
Are you getting RF when your condensers are plugged in with NO phantom power applied or is it WITH phantom applied?

Do you have power cables, speaker cables or low-voltage signal cables coiled? This should not be. You can even have parallel cables causing you problems.

What mixer are you using. Some mixers have better RF rejection than others. Some older first and second gen Mackies, Yamahas, Behringers, Phonics, Soundcrafts, etc have BIG RF issues.

If you have RF coming through unpowered speakers with no cables attached, you will likely all have brain tumors and cancer (kidding, it's not that bad). But you will never shake it. If it is coming through with your speaker cable attached, you might think of using shielded speaker cables. You might also think of reducing the speaker cable run length, locating the amps directly behind the speakers.