Originally Posted by rabbit73
I found one of the images they show for the 7003 interesting. It might be a way to combine the signals from two antennas aimed in different directions by creating a mini-headend.
Another method, which would work when you desired to insert just one RF UHF channel (with sub-channels) from an antenna pointed in a different direction, would be to use a single channel converter, such as the Pico Macom XUV. This product is discontinued but you can still find used units on ebay. Also, it was sold under other brand names and was aimed at the CATV and MATV market, so units have been pulled from those systems and put up for sale. A UHF channel received from an antenna would be "mapped" to a lower channel for distribution on an analog CATV or MATV system. For the 2 antenna application, we would map the second antenna's UHF channel to, let's say, a channel in the VHF-LO range (rf channels 2-6). I choose VHF-LO because these channels are less desirable for digital OTA TV because of noise problems, so very few are in use, and it should be possible to use a VHF-LO and VHF-HI filtered combiner in your system to insert the converter's output. Channel Master used to make a product called "Join-tenna" which might work.
How it would work: Let's say I use a fringe area antenna to receive (hypothetical) RF channel 39, virtual channels 40.1, 40.2 and 40.3, from a market outside my normal reception range. I would then use my UHF to VHF converter to map RF channel 39 from my antenna to RF channel 3, and a combiner to insert the channel on my system. At each TV set or converter box, I would rescan. The signal on channel 3 is found and becomes associated with virtual channels 40.1, 40.2 and 40.3. To the user, the translation to RF channel 3 is (almost) transparent. They just see it as a new virtual channel, designated 40 with sub-channels 1-3.
I have experimented with this idea, using the Pico Macom XUV to translate a channel with a strong signal, and proven the concept. If you wish to implement, I strongly suggest proving that you can receive the desired channel with a dedicated antenna, TV set, and, if needed, ATSC converter box. Make sure that the signal produces a watchable picture (infrequent pixelation and dropouts).
Having passed that step, I strongly suggest locating a converter that maps a UHF channel to a channel in the range 2-6. Converters were shipped from the factory with specific UHF to VHF mappings, but were field re-assignable within some limitations. The VHF channel needed to stay within the same range (VHF-LO, MID, HIGH or Superband). Lettered channels A-I were MID, higher lettered were Super. For output channels 2-6, there were no restrictions on the input UHF channel.
It will probably be very difficult or impossible to find a converter factory set for the desired pairing. I suggest getting assistance from someone experienced with RF modulators, amplifiers and filters, to perform the adjustments for remapping.
If you live in an area served by 2 clusters of transmitters, and can't find a good compromise direction for your antenna, this method would be useful for adding a small number of desired channels from the second cluster. These added channels might appear on RF channels 2, 4 and 5, which should be spaced far enough apart so adjacent channel interference might not be an issue. (There is a gap between 4 and 5, and 6 is often used as low power analog channel.)