You might want to experiment with a preamp for the 751 before going to a larger antenna. Consider the Channel Master 7778, the RCA TVPRAMP1R, or the Antennas Direct Juice. The 7778 and the RCA have an FM filter, but the Juice does not. The Juice, however, is resistant to overload and does have a 4G LTE filter to attenuate cell phone signals that might interfere with TV reception.
The RCA is very inexpensive, and usually does well, but has a history of quality control problems, including a problem with the combined/separate switch. It sometimes doesn't make good contact with a VHF antenna when in the separate position, but you will be using it in the combined position.
If the antenna is outside, the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.
Quote:
Originally Posted by ledude
Gosh, its so unfortunate that there's a strong local FM signals that's affecting the TV reception. I noticed it lately, when I watched the local PBS channel at 9-*. The strange thing is channel 11-* for CW is not affected at all.
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I don't consider your FM signals strong enough to be a serious threat to TV reception, but I did say they
might be a problem. If they are a problem, the FM filter in the preamp should be sufficient. The FM signals are not strong enough to cause fundamental overload. It is, however, possible that the second harmonic of a strong FM signal
might interfere with a VHF-High signal.
http://www.fmfool.com/modeling/tmp/f...9/Radar-FM.png
Channel 9 is 186 to 192 MHz
KMPS-FM is on 94.1 MHz
Its second harmonic is 188.2 MHz, which falls in the middle of Channel 9.
Grounding the coax with a grounding block will reduce the chance of interference.
I hope your TV has a signal strength indicator to tell you if you are making any progress.