jakdedert wrote:
Ray L. Volts wrote:

"Michael Kennedy" wrote in message
...

Channel 2 NBC? Are you in Central Florida?



Houston (KPRC).


I have all kinds of weird problems with channel 2.. doesn't matter
what tv vcr or tuner I use. There is always sort of a double picture.
I've experienced at friends houses also. Some times it seperates so
bad you can't stand to watch it. It is very odd because the audio
will be perfect but the video is awful..



Sounds like ghosting. You might try a variable attenuator; hook it up
to an A-B switch box so you won't have to readjust it everytime you
change from channel 2. Yes, every device you put in the line,
including switch boxes, causes signal loss (exception being in-line
amps) and most introduce noise. But if your ghosting problem is due to
too great a signal strength, perhaps the device-induced losses won't
affect the other channels.

Alternatively, maybe there are nearby objects (e.g., tall, metal
warehouse or shed) which could be delivering a reflected signal,
resulting in the ghosting.


In case the OP is not familiar with ghosting (or Google, he could look
it up); it's a function of a reflected TV signal arriving at the
antenna, some number of milliseconds after the direct signal. IOW, the
exact signal arriving at the antenna, slightly delayed in time from the
direct signal. The 'ghost' is that signal dispayed on your TV screen.
You can actually measure the exact interval of reflected to direct
signal by the percentage of screen real estate between the two, although
that's only of academic interest. What's important is that the display
scans the reflection slightly later than the direct one, causing it to
appear at some distance to the right. In more severe cases, the sound
is also affected, especially on various scenes.

What he needs is some way to either eliminate the reflected (or direct?)
signal...or to make one or the other so much stronger that it is no
longer a problem. A highly directional antenna is usually the only way
to do so (aim the antenna so that the ghost disapears), but in many
applications is still not do-able.

I had a bad ghost on local channels last week which turned out to be
caused by an unterminated output on my distribution system.

jak

The problem with the Sony was not ghosting. The Sony was generating so
much self interference (probably from its switching supply) that with an
indoor antenna (not cable) every station showed swirly lines AND NEARBY
TV's SHOWED THE SAME INTERFERENCE WHENEVER THE SONY WAS ON!

-Al