shreyas1

Hello! I have run into an issue with a customer install using a Channel Plus modulator in a home. All the cable lines are home run, and are distributed. The incoming cable line and the modulated signal are connected together using a combiner, and then fed into an amplifier, then distributed to the home. I have noticed that when the modulator is running without the cable line hooked up, the signal is perfectly clear (running on ch 80). Once the cable line is added to the combiner, the modulated ch (80) shows a great deal of static. I'm unable to figure out what the problem is. Has anyone experienced this? I have tried multiple modulators, but it seems that the same issue occurs once the cable is introduced. Any help would be greatly appreciated!

Actually I was just messing with it on my workbench and managed to figure out the settings. The face comes off and there are 2 roll-selectors for each input. Looks like everything should be good to go form here. Thanks for all the help and advice!

That's what I figured when I started looking around at the different models. There would only be 1 actual channel lost, so that shouldn't be a problem. The modulator that is currently there is an older ChannelPlus, Model:4231. I can't seem to find any buttons on it to program the channels. It is a 2 channel modulator feeding channels 80 and 89. Any advice on where/how to change the channel settings? I'm assuming that it has dip switches inside, but I'd still be at a loss for what combination without the manual. Thanks again!

I think I'm going to go the route with the notch filter. I spoke with the homeowner who said that the issue just started a few months back, so I'm going to assume that either the Cable co has put some digital channels on it, or like you said are amplifying the entire series of channels. Luckily, channels 75-80 are not currently being used on the homeowners TV's, nor do they have programming offered on them. Also, the current modulator is set to run on Ch. 80, which is even better. Thank you for your help. I'm going to order a: Leviton Passive RF Notch Filter 75-80 47690-NFA This seems like it will work. Let me know what you think though. I'm a little confused on what you mean by putting an amp or notch filter on the cable line to prevent distributing the signal outside of the home. Would using the notch on the main cable line, then combining it with the modulated signal and then feeding the amplifier and distributing to the home cause this ffedback? I'm assuming that it wouldn't, but please let me know if I have it wrong. I truly appreciate your help, I was completely stumped, but this seems like the most logical solution.