Len,
It would help if you tell us exactly what kind of problem you are having.
There are many models of ChannelPlus (now called Linear) so you may want to start at their web site, http://www.channelplus.com/products_rf.html to find some information.
The most common problem that I seen with DISH receivers and ChannelPlus modulators is when the modulator is set to a channel the same as, or close to, the channel that the satellite receiver (like a ViP receiver) home distribution is using.
It would help if you tell us exactly what kind of problem you are having.
There are many models of ChannelPlus (now called Linear) so you may want to start at their web site, http://www.channelplus.com/products_rf.html to find some information.
The most common problem that I seen with DISH receivers and ChannelPlus modulators is when the modulator is set to a channel the same as, or close to, the channel that the satellite receiver (like a ViP receiver) home distribution is using.