Having trouble getting fox (69.1) in San Diego

#1
TV fool:

TV Fool

I cut the cord and clamped a cheap rooftop antenna to my old directv mount, facing roughly 300deg, about 10' off the ground. I used the existing DTV grounded coax cable into a TiVo premier XL. I can't figure out why my fox reception is so spotty; I get PBS just fine, which appears to be coming from the same tower. Any ideas? Giants are playing tomorrow am and I hope to get this fixed soon! I will try reorienting the antenna to 280deg to better line up with fox (am I correct in assuming that 0deg and 180deg are the same for this antenna?)

Here is my antenna:

Amazon.com: Eagle Aspen Dtv2Buhf Directv 2-Bay Uhf Antenna: Electronics

Thanks a lot!
 

dkreichen1968

Moderator
Staff member
#2
Your antenna has a reflector on it that makes it directional. The stations you are receiving from the back are a lot more prone to multi-path interference since a bounced signal may be close to being as strong as the main signal. There are very few bi-directional commercial antennas. The Channel Master CM3010 is one I recommend on a regular basis. Short term, or possibly long term, adjusting your current antenna may be all you need. With multi-path small changes can make a big difference.
 
#3
Thanks - I flipped the orientation so it is facing ~110 deg, and now fox comes in much stronger. Oddly, NBC is now a bit choppy (39.1) even though its from the same tower. Any ideas why that might be?
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#4
:welcome: Socalrider,

Your antenna is directional and (in theory) the screen blocks signal reception from behind the driven 'whiskers' or elements. According to your survey, your closest FOX affiliate is KSWB-19 at 101 degrees: if your antenna is pointing west @ 280-300 degrees, the screen is trying to block signals from the east.

I have a copy of the same antenna you are using and if you want to test it as a bi-directional antenna, the screen can be removed by drilling or grinding off the heads of two rivits. If it doesn't work, the screen can be added back to the antenna using two sheet metal screws, new rivits or machine screws.

Jim
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#5
Thanks - I flipped the orientation so it is facing ~110 deg, and now fox comes in much stronger. Oddly, NBC is now a bit choppy (39.1) even though its from the same tower. Any ideas why that might be?
OTA HDTV signals tend to arrive at receiving antennas in hot and cold layers, something like an ice cream sandwich: if possible, raise your antenna 6" and try it again - then raise it another 6".

I receive one channel here with my antenna located within an 18" height range and being any lower or higher (even 20 feet higher) get me no useable signal.

Jim
 

dkreichen1968

Moderator
Staff member
#6
Thanks - I flipped the orientation so it is facing ~110 deg, and now fox comes in much stronger. Oddly, NBC is now a bit choppy (39.1) even though its from the same tower. Any ideas why that might be?
Multi-path. In analog it caused ghosts. In digital it causes break ups since the tuner gets confused on which data stream it needs to be decoding. It's caused by signals bouncing off objects causing there to be one or more signals that are out of phase with the main signal, and it can be different for different stations broadcasting from the same location. One of my local stations has both a low power and a full power transmitter that broadcasts the same programming (both UHF). My current antenna gets multi-path on the LP and is fine on the FP. It won't be a problem until and unless they reprogram the LP. Antenna adjustment can be a matter of trial and error. Especially since you have signals coming from so many directions.
 
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