TV coaxial jack not working right

Everytime I try to hook up the cable or vcr to the coaxial jack on this tv the picture has a lot of “snow” in it. The dvd is hooked up to the red/white/yellow (rca jacks??) and works perfect.

Facts: 31 inch Sanyo (bought it at walmart a couple of years ago, but it suits (or did) my needs.) It’s nothing special, but it used to always work great. Has stereo and connections for my dvd/surround system and wide-screen movies look great on it.

I paid $400-500 I think.

How hard will it be for me to try and replace that jack? Would something like that cost very much at a typical repair center?

Dish network is coming by this week to install a dish. Do those boxes have s-video or rca connections that will help me bypass using the coaxial input? If so, then I guess this thread is moot.

Anyone?

I’m no TV techie, but it sounds more like the tuner in the TV is having a problem, not the jack. If it was just a question of a loose connection at the coax jack, jiggling it or squeezing it would probably produce some change in the snow. Try it, and see if it makes any difference.

The red/white/yellow connections, in effect, bypass the tuner, and feed the tube more directly. What happens with rabbit ears (assuming you’re close enough to at least one broadcast station to get a decent signal)?

If the tuner is the problem, it would almost certainly cost more to repair than the TV is worth, or, for that matter, than a new, similar TV.

  1. Are you sure your TV is set to the correct channel for the output of the VCR / Cable box you are attaching? If your VCR output is on Ch 3 and your set is tuned to Ch 2 or 4, you would see the symptoms you are describing.

  2. The Dish Network receiver should have both S-Video and RCA connections.

If the jack is soldered onto the pcb there is a chance the solder broke, just heat it up again if so. Also don’t coil the cords, straight runs are best. Last make sure you are using the correct tuner channel, 3 or 4.

Use the satellite receiver’s RCA video or S-video connection and avoid the RF (coaxial) connector entirely. Aside from your TV’s RF input not working right, it avoids a lot of unnecessary processing and will give a better picture.

What happens internally is the dish box produces a video signal and a stereo audio signal. This is what comes out on the red/white/yellow RCA jacks. For connection to older TVs, the dish box takes the audio and video signals and mixes them together and converts to an RF signal - typically channel 3 or 4. The process is called modulating. In the TV, you’re tuning to that channel 3 or 4 to produce a video signal and an audio signal - this is called demodulating. Aside from a lot of mixing and mashing around, there’s no guarantee that the audio will emerge in stereo.

Ditto everything said so far. Some other things to check:

Quality of the coax cable and connectors. Even if it once worked well, it can literally wear out, been abused, connectors come lose, etc. There are also an unbelievable number of people with “push-on” coax cables which are absolutely horrible.

The connectors can also be dirty. I use “DeoxIT” once a year on all connections to keep corrosion from building up. (Luckily I have a can within arm reach right now so I can check the capitalization.)

You should also check that everything is properly grounded. All the devices connecting to the cable should be plugged in correctly with no funny business. (I also clean my cable ground twice a year.)

If nothing changes when you jiggle the jack, then I’m betting on a crappy cable or corrosion.

What herman_and_bill said is a possibility, otherwise you have almost no hope of fixing it yourself. Today’s sets are very highly integrated and TV manufacturers aren’t exactly forthcoming with troubleshooting information. If you were really determined and had some electronics background (which I’m guessing you don’t) you could try the folks on sci.electronics.repair; this sort of thing would be right up their alley.

But since your Dish set-top box will have a connection for your antenna or cable, you won’t need the TV’s RF input any more, although you may need to invest in a passive switchbox (or switch inputs through your home theater receiver if you have one).

Thank you all. The Dish reciver does have both s-video and rca, so the problem is moot.