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Old February 7th 04, 11:31 AM
Crazy George
 
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Joel:

Avoid adjacent channels, your n=1, n-1; and then have no two channels spaced
by the same separation. Starting with 39 and 43, have no other pair 4
channels apart. So, you are already in trouble with off air signals (47 -
43 = 4). And so on for the rest of the channels. The n+5 or 9 is for IF
beats which will depend on the image rejection of your particular equipment.
Difficult to predict exactly without performance data. There has been
published an algorithm for most effective use of channels, but you don't
have enough channels to need that sophistication.
"Joel Dorfan" wrote in message
...
We have a number of UHF television channels as well as
VCR's, Satellite decoders etc. all with UHF modulators.
One needs to carefuly choose which UHF channel to modulate on when setting
up the VCR, decoder etc. so that they dont interfere with each other or

the
off air UHF signals.

Some time ago I came across a table that assisted with the choosing of
various UHF channels (taking into account the off air channels) to avoid
multiples and adjacent channel interference. I can not seem to find this
table anymore.

Do you know of an algorithm to use to assist with the above? The UHF
spectrum for TV video is from 21(471.25 Mhz) to 68 (847.25Mhz) with audio
being 6Mz higher in frequency.

If for example we have UHF signals on channels 39, 43, 37 and 47 which of
the remaining channels would be acceptable to use for the modulation of

the
other devices.

It has been suggested to avoid n-1,n+1,n+5 and n+9 where n is a UHF

channel
currently in use. Is this correct?

Thanks

Joel

ZS6CBA