Originally Posted by Jimsathome
My question: Can the OTA input be from a cable supplier as I've read elsewhere? The Cable supplier uses all Digital Cable boxes with no analogue channels or FM signals at all. If so this would certainly tidy up an install having both sources on one cable until diplexed at the Reciever / Cable Box.
YES, you can Jim.
I do it and it works just fine.
The reason it does is all about frequencies.
Cable and OTA broadcast will always fall within the 50-860MHz range, where as the LNB output starts at 950MHz and can go up to 2.15GHz.
The diplexer really acts like a frequency filter/combiner.
In the 5x8 multiswitch, the lower 50-860 signal get combined on the coax with the much higher satellite signals.
Then you use a small single diplexer on any number of lines that need to filer/tap off the cable/OTA TV signal to be used.
In my case I had 2 coaxes running to the top of the bedroom closet where I have a SD and an FTA box.
I added the local cable feed onto the SD feed and ran the TV line from the diplexer to the TV and the SAT line to the 505.
The diplexer doesn't care if the signal is NTSC, ATSC, QAM, clear or encrypted. All it knows about if simple RF frequencies.
It's a great way to send Cable/Antenna signal + satellite on a single coax.
This technique was common a while ago when TV antennas had separate VHF and UHF and were combined in a similar fashion on a single feedline.