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Old March 17th 14, 07:38 AM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.misc
Jeff[_18_] Jeff[_18_] is offline
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First recorded activity by RadioBanter: Jan 2014
Posts: 250
Default Quad shield coax & dielectric?


No one said the NTSC had to be noiseless. But the 43dB is a bit high,
even for older sets. Input from the cable tv company to our equipment
was 10-20dB; we tried to push 10dB to all of the outputs but never had a
problem even down to 7dB (the lowest we would let it drop to).


That makes no sense; a 7dB CNR would be pretty much unwatchable on
analogue, it would be a very very noisy picture, if it even locked at
all!

Jeff


I'm not talking CNR - I'm talking signal strength. 7dbm is plenty of
signal. Most later TV's would work even at 0dbm.


Well the "43dB"that you were stating "was a bit high" was expressed as
CNR, so it is reasonable to think that your other figures were also CNR
as you did bot state otherwise.

Also 7dBm (5mW) is a very high signal and would cause most sets to
intermod like crazy. Perhaps you meant 7dBmV.

Jeff