On Mon, 03 May 2004 17:15:07 GMT, ITM wrote:

On Mon, 03 May 2004 18:02:12 +0100, Andy Hall
wrote:

Although the channels need to be chosen carefully to avoid
interference of the modulator harmonics with the TV signals.

This involves checking the channels in use and avoiding those that are
3,5,7 and 9 channels away from any terrestrial signal.


.andy

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All of my existing channels are in the range 23-50. If I use the twin
RF modulator from CPC, and put the cameras on channels 53 and 56 then
in theory there should be no problems, right?

Sorry, but it isn't as easy as that.

Apart from avoiding being on the TV channels, you also need to avoid
being on (N + 5) and (N + 9) away from them as well or you will get
interference.

This means looking up the exact channels in use by the terrestrial
transmitter(s) and avoiding those that are 5 and 9 channels away, as
well as any that are adjacent.

http://www.wrightsaerials.tv/Resourc...hannel%205.pdf


In this case, would I have any need for channel pass filters or level
adjusters??

Channelising filters will help with adjusting everything to equal
level.

www.teldis.com



..andy

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