hd7694p vhf problem

[FRENCHPARK43]

I have an hd7694P in my attic with 100 ft of rg6 to my tv - no preamp.
I live in the new york area (07757) andI can receive UHF channels OK
as well as ch13 -VHF( ~211 Mhz ). However I can't receive channel 7 ( ~175 MHz) .

TV shows 0 signal strength on CH7. It seems as if Ch 13 is OK , CH 7 should be too. Any help will be
appreciated.

[winegard]

Good morning frenchpark43,

You correct that if you are receiving a good signal on channels 13 the antenna is working properly. It sounds as tough the issue is the antenna placement. The antenna can pick out one channel not to work on. Try relocating the antenna in a different location in the attic where you can find a stronger channels 7 signal.

[FRENCHPARK43]

Thanks for the info. I will try moving the antenna around. BTW how much does the attic placement cause vs a roof instalation. I have an older antenna already mounted but I don't want to go climbing on the roof to change it out due to old age but I may if it is worth it.

[winegard]

Installing an antenna in an attic can cause a signal loss of 50-90% depending on the materials used in your roof and other obstacles. If possible mounting an antenna outdoors will be your best bet.

[TomV]

What signal strength are you receiving chs 11 and 13 with? I find it hard to believe that 7 has 0 per your TV if the others are working. If so, then it I would consider the TV as a possible culprit as well. Can you receive ch 58 (WNJB) on VHF 8?

[TomV]

Another thread about ch 7 VHF having issues was answered by a Winegard responder. He suggested that a harmonic of an FM station might be overwhelming ch7. Since ch 7 should have a solid signal level at your site it would take a hefty harmonic to do that. The FM signal would be in the 88.5 MHz region.

I looked at FM Fool for the FM stations at 07757 and found 3 with harmonics that would be in the band for ch 7 . Ch 7 is between 174 and 180 MHz. The FM stations with harmonics in this region would be between 87 and 90 MHz. You have 88.9 (strong), 89.3 (10 db weaker) and 88.1 down another 7 dB from 89.3). FM Fool also shows that the FM stations are coming from the south, whereas ch 7 is from the north. This should reduce the power of the FM since your antenna is directional. You may be getting some reflection of the signals that would bypass the directionality of the antenna.

Considering the signal strength at you site, you could try rotating the antenna a bit (30 degrees) and see if that helps with ch 7.

A distribution amp with an FM trap, or just an FM trap itself, could show if the FM stations are culprits.