Radio Bleedthrough on Long Cable Run

[tbradshaw]

TV 2 on my 722k is picking up some sort of radio interference. The cable run is fairly long...from the basement to the 2nd floor. The interference is clearly audible when no satellite signal is present and not affected by the TV volume. I'm assuming the cable is picking it up.

What sort of filter would I want to look at to knock this out of my signal?

Thanks.

 

[RickDee]

I think you should check to ensure the cable shielding is well grounded. If the shield is grounded it should not be picking up stray radio signals.

 

[tbradshaw]

And they would ground through the connector...through the TV? Somewhere else? Should I be looking at the installation of the connector to the cable at the TV end?

 

[boba]

Are you sure the intefering signal is coming from the cable? You can't hear a radio signal it has to be tuned by a tuner to convert it to something you can hear. A radio signal picked up on the coax usually shows up as distortion in the video not audio.

 

[tbradshaw]

Well, it disappears when I disconnect the cable, either at the wall or at the TV. That makes me think it's at least being transmitted by the cable.

I had some suspicion that it might have been a Dish music channel but I just heard commercials which makes me pretty certain it's radio...earlier I'd heard a DJ counting down the week's top 10 hits.

 

[Bobby]

Are you sure the intefering signal is coming from the cable? You can't hear a radio signal it has to be tuned by a tuner to convert it to something you can hear. A radio signal picked up on the coax usually shows up as distortion in the video not audio.

That's not entirely true. If there is a transmitter close by that has a very strong signal it can induce into many things. You don't necessarily need a tuner. As an example, many years ago, when I was a telephone repairman, I went out on a trouble call for radio over the telephone conversation. We had filters for just this purpose. One way was to put capacitors in a particular array at the protector where the line connects from the pole to the house wiring. We also had a special filter that we could use which was a lot more advanced, but quite expensive. None of these fixes worked. I was out on again on a several time repeat call, this time with my boss and his boss. My bosses boss thought I wasn't doing enough to help this lady out. I asked the lady to open her refrigerator door. She did and, BOOM, It was like a loudspeaker. There was religious music coming out of it. The radio station, one of those religious ones, was transmitting way over its assigned power level. A report was made to the FCC and we never heard from this lady again.

 

[Lord_Vader]

I asked the lady to open her refrigerator door. She did and, BOOM, It was like a loudspeaker. There was religious music coming out of it.

LOL

 

[rexlan]

Holly bread and butter Bat Man!