Quote:
Originally Posted by KCount
I am curious about the DB8e and their swivel panels and losing possible signal gains by rotating half of the antenna.
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Look at the data sheet for the DB8e here:
DB8e web page Click the Documents tab, and open the Technical Data pdf file. As you scroll down through the pages, you can see the max gain (with both panels aimed in the same direction) go from about 16-17 dBi down to around 9-11 dBi when they're 180 degrees apart (page 8).
9-11 dBi is about the same gain as the dB2e all by itself
(DB2e link - same drill to see the plots), which is literally 1/4 the antenna the DB8e is, and 1/4 the resulting signal strength. When you aim the panels away from each other, some of the signal received by one is reradiated back out the other. That's the problem with combining similar antennas aimed in different directions into a single downlead.
If ~10 dB is enough gain, and that's not chicken feed by the way, then the worst-case aiming (180 degrees apart) at two different antenna farms is a very elegant way (IMO) to accomplish this. Less than 180 degrees and the gain goes up.
Quote:
Originally Posted by KCount
In this setup it looks as if a rotator would certainly be needed.
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Some TVs allow rescanning to add channels. My cheap little Vizio has that feature, as I found this weekend when playing around on a boat. My big Panasonic plasma doesn't. So if using a rotator, and if the TV doesn't allow adding channels, you'd have to rescan every time you rotate the antenna enough that some drop out and others are receivable. That's something to consider if pondering a rotator vs multiple antennas and multiple tuners.
Multiple tuners would be a deluxe solution, using a computer as a media server. My neighbor is running three antennas into three tuner cards in his dedicated media computer system, with a seamless on-screen channel menu that covers all the channels. I haven't gotten that far yet, but it's an interesting solution, and about as integrated as one can get (includes DVR capability).