Cable TV Grainy

[DrJAG]

After owning our Legacy for almost 2 yrs, I finally hooked up to cable TV. Got great picture on main TV, but picture on the other TVs was grainy, especially the bedroom TV. Picture using antenna is fine on all three TVs. Any ideas what to do to fix this. I did make sure the coax connections are tight. Also, I noticed two coax cables behind the video switch box that are not connected. One is gray and the other is black. What are each of these cables used for? Thanks!

[SeaDog]

the first thing I would check is to ensure your antenna booster is not on.

[formerFR]

I can't see how it would be the coach coax wiring or connections if the Antenna signal works well on all the TVs... if you have a BOMB(Coax/HDMI switch box) generally the coax from the outside connection comes into it, then out to all the TVs - the same with the Antenna signal.

Is the box pressed for 'CABLE' for each of the TVs?

with the switch box, it probably doesn't matter if the 'ON' button is pressed, as Cable doesn't require it, but it probably would not interfere with the Cable signal even if it is.

[bob213]

Did you switch the input from antenna to cable on the other tv's before doing a channel scan?

[DrJAG]

I did make sure antenna booster was off, although there was no difference when it was on. Tried pushing all buttons on video box. Also selected cable on each TV and did new channel scan. I'm thinking it could be weak input signal or bad video switch box. Guess I could switch output cables and see if bedroom tv remains grainy or clears up.

[Bama Rambler]

I could be a bad F connection at one end or the other of the cable.

[captnrick3]

I've been fiddling with ours to try to duplicate that problem, so far I have not been able to. All TV's are the same.

[DrJAG]

Update.... finally at campground with cable. Hooked up and good picture on all three TVs. Guess I had weak cable signal previously.