Digital TV

Bob DeMattia
Wed Nov 11 13:55:23 EST 2009

Although the roads from Needham to Brookline aren't very direct, the
radio waves don't
see things that way.  Parts of Brookline are on 2 or 3 miles from the
antennas.  The RF
fields are very strong there.  The ingress could be right through the
back of the TV itself
if the TV is poorly designed.

I have an RF site in Brookline that was suffering overload from
analog-channel-7's transmitter
a while back.  At least the transition to DTV solved one problem for me!


On Wed, Nov 11, 2009 at 1:45 PM, Mike Fitzpatrick
<> wrote:
> Sounds like you are suffering from bad ingress. It's the same as what would
> happen with leaky cable tv wiring on channels, 2, 4, 5, and 7.
> Where you would see the cable's signal and the over the air signal
> simultaneously. Because the cable system's signal was different than the
> over the air.
> (RF Phase, RF frequency shift, etc), the signal would look bad. With your
> situation where you have a master antenna system, you have a cable driven RF
> signal on channel 19 (WGBH-DT) and over the air leakage. The two digital
> signals being entered into the box could cause all kinds of problems, such
> as the one you're describing (Because the master antenna system will
> "adjust" the RF slightly, to put it non technically). I come to this
> conclusion for two reasons. 1) you say playing with the connector helps., if
> the connectors were seated properly and spliced correctly, touching them
> would make absolutely no difference at all. And 2) you said shifting your
> body changes things, well your body affects over the air RF. If it is a
> closed master antenna system, yet shifting your body changes the effect,
> then you have ingress getting into it somewhere. You should be able to move
> all over your room and never see an effect on the signal. Have you tried
> disconnecting the master antenna system and just putting in a passive set
> top antenna? In Brookline, I would expect you'd get just about everything
> crystal clear.
> --Mike
> -----Original Message-----
> From: On Behalf Of Larry Sochrin
> Sent: Monday, November 09, 2009 12:04
> To:
> Subject: Re: Digital TV
> Might as well ring in from Brookline Village...
> are working, the
> image is better than it was prior to digital.

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