The CGC Communicator Newsletter Web Posting

A NEIGHBOR'S ANTENNA CAN AFFECT YOUR DTV RECEPTION

Here's a little something to be aware of that I've observed at my home:

I just installed a DTV converter box (after all, why rush into these things).  I get about 62 channels of various stuffs with no problems.  When I first installed the box I was able to get KDOC's DTV fine.  My house antenna is a combination VHF/UHF Winegard model PR-7010.  I don't need a lot of gain since I'm in Glendale and line-of-sight to Mt. Wilson.

The next day I was having problems with poor lock-up and continuous dropouts, particularly on KDOC-DT.  I traced this to reflections caused by the orientation of my VHF and UHF [professional] measuring antennas, which are obviously re-radiating signals.  Rotating the measuring antennas a few degrees immediately cleared the problems and I regained a fast and stable lockup.  What's interesting is that the two antennas are approximately 50 feet apart at approximately the same height.  In the past I'd been aware of a slight ghosting of the analog signals on the house TVs depending on the orientation of the measuring antennas.

The bottom line here is that it's quite possible for a neighbor's rooftop TV antenna to cause multipath into your own TV antenna resulting in severe problems with your DTV reception.


Burt Weiner/K6OQK

Burt I. Weiner Associates, Broadcast Technical Services
Glendale, California  U.S.A.  --  biwa (at) att.net

February 20, 2009

Posted by Steve Blodgett
Earthsignals.com