Anyone have any experience with this antenna? I'm getting it today first to pull in a weak station about 40 miles away and I hope to bring in some stations 70 miles away. I also have a question on the CM 7777 preamp. There is a VHF/UHF combine input which I have a large radio shack combo antenna plugged in. There is also that UHF only input which I assume I can just plug in the 91XG. Is this correct? I'm also debating as to if I should put the 91XG on the same mast as the VHF/UHF combo antenna. Will this cause interference? Thank you for your input.
91Xg Antenna and CM 7777 preamp
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Combining antennas is not quite as easy as that. If you had a VHF-only antenna and a UHF-only antenna (the 91XG) you could use the CM7778 (not the CM7777) to combine them. But because one of your antennas is a VHF/UHF combo, you are trying to combine two UHF antennas. Often this will result in worse UHF reception on many stations rather than improving it. This is because a station signal will be picked up by both UHF antennas, but because the antennas are different, and in different locations,and you have different cable lengths between the antennas and the combiner, the two signals will arrive at slightly different times - essentially what you are doing is creating multipath. This effect will vary depending on signal strength, the frequency and direction of the station, and the direction in which your two antennas are pointed.
There are a few people around who seem to have a lot more experience than I do of combining antennas, maybe they will reply. You could try sending a PM to rick0725 who often posts here....
Oh, and the 91XG is one of the best UHF antennas...
I'm looking to pull in channel 26 in NOLA better and the Baton Rouge stations in HD
from Covington. Thanks for the reply. Anyone know of a combo I could use to keep the old radio shack combo antenna and run the new X91 through the UHF plug on the CM7777 preamp?
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You can combine your combo antenna with the 91xg through a cm7777 or cm7778 with the internal switch set to separate. the 2 antennas should be spaced at least 3.5' apart. the ports are isolated by 30db which is adequate. I have tried adding filtering and have found very little improvement.
the combo must be used for vhf/fm and the 91xg for uhf. you should not use a standard 2 way combiner to combine the antennas.
If you do not have a dual input preamp you would install a cm0549 vhf/uhf combiner prior to the preamp.
selection of preamps with the appropriate gain based on your conditions are important in all installs to quard against overload. I do not like to use a high gain amp under 30 miles, stations in yellow, short coax runs and minimal splitting. In the suburbs the winegard hdp 269 preamp is best.
it is a good idea to amplify uhf and pass vhf in cases where the vhf signal is strong. this may alow you to get away with using a high gain amp like a cm7777 or cm7778 for example. attached is a wiring example for this scenario.
included in the example is the winegard ca8800 fm/tv splitter. this is used in place of a standard 2 way splitter to send an fm signal to your receiver off the combo antenna with less insertion loss (.4 db vs 4.0 db) if you are interested in that. the ca8800 is available here.
http://www.summitsource.com/winegar...r-combiner-ac-passive-part-ca8800-p-5703.html
I combine a 91xg with the hd8200p combo with hdp269 preamp, cm0549 combiner,only amplify uhf, and send the fm signal to a few receivers with the ca8800. I was unable to use the cm7777 or cm7778 at my home 19 miles from towers because of overload issues. The setup works great and highly recommend it.
the 91xg tames multipath nicely. I was unable to use the cm4228 here.
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Thank you very much for your advice. So I would have to open up the CM7777 preamp and put the switch to separate? What about the fm trap switch, leave it alone? I've never understood what that means. Thank you very much again.
http://www.solidsignal.com/prod_display.asp?PROD=ANC7777&xzoom=Large-3#xview
the switch inside the amp is set to "separate" in order to utilize the separate vhf and uhf ports on the preamp.
If you desire to receive fm in your setup, the switch is set to "out". if you do not wish to receive fm or if you experience interference due to strong fm signals set the fm switch to "in". switching to "in" will engage the built in fm filter and attenuate the fm signal.
let us know how you make out.
If you desire to receive fm in your setup, the switch is set to "out". if you do not wish to receive fm or if you experience interference due to strong fm signals set the fm switch to "in". switching to "in" will engage the built in fm filter and attenuate the fm signal.
let us know how you make out.
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