[CQ-Contest] Bandpass filter

Tom W8JI w8ji at w8ji.com
Tue Jul 3 11:28:09 PDT 2012

> Correct for fully functioning and tuned amplifier.

40 milliwatts or so is a correct worse case for any amp, in or reasonably 
out-of-tune, unless someone homebrewed something terrible.

Very few radios are damaged by 200 milliwatts, or 23 dBm.

The damage problem is always fundamental energy damage of a receiver.

The only harmonic issue is interference.

> Regarding a far-away receiver, correct.
> An immediate next property neighbor might get a frying shot into the front 
> end.

>From fundamental, which takes a receiver filter at his end to stop, but 
never from a transmitter harmonic. It may help sell transmitter filters to 
worry about harmonic damage to a receiver, but it is an imaginary worry, not 
a reality. A transmitter filter is really only to lessen interference 
problems operating near harmonic frequencies, not at all required to prevent 
equipment damage.


73 Tom

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