COM7 keeps disappearing

[prpr]

I wasn't talking about your COM7, I was talking about COM7 generally

You said "with COM7 everything is right on the edge of working". Why isn't my particular COM7 included in your general case then? You said "everything". Clearly it's not "everything" and your sweeping statement is therefore wrong.

do you really think with differencies of 200kWatts down to 6kWatts for COM7 that it isn't going harder to get a useable signal.

Of course it's going to be "harder", but it will affect the people most in the fringe areas, not the vast majority of users served by the TX who will be well within the service area.

A lot of users who can easily receive the main MUXs are going to have difficulty receiving COM7

"A lot"? That's a vague and thus subjective and meaningless term. Percentage wise it is going to be a lot lower than the percentage of people who have absolutely no problem whatsoever. That doesn't count as "a lot" in my book.

 

[hairy_mutley]

Have you looked at the beam pattern? Some of the com groups (especially 7 & 8) are quite directed and may not be aimed at you.

 

[hairy_mutley]

Ok, forget that, Winter Hill COM7 is pretty-much Omni directional. COM8 has a notch in the SE (around 155 to 175).

 

[philbean]

I did add a booster to try and fix it. Should I try replacing that with an attenuator then ?




All this to get Talking Pictures TV !

 

[Trev]

Should I try replacing that with an attenuator then ?

See post #19. Anything is worth a try.
Too large a signal will overload the input stages to your TV and cause an apparent total loss of signal. But my suspicion is that is not the case in your situation as it would likely affect the stronger multiplexes first.
I get a loss of signal on my HD channels sometimes: well the TVs and Hummy T2 all report zero sig and zero quality, but my posh meter says that the actual signal strength does not alter a bit. In the analogue days, we used to get a lot of ghosting from continental stations (co-channel interference) and I have put down the loss of signal to that.

 

[grahamlthompson]

The FEC used on COM 7 to maximise space could well make it a lot less robust than the main MUX. Certainly worth trying a variable attenuator and watching it's effect on indicated signal quality.