> The only way to tell what the high-order IMD levels are is to tune out
> there and look for them.
......and you must have a reasonable S/N ratio to start with and know how to
use a receiver to do a proper test.
I can think of a specific example...
A KB3 on 160m who is about 20 over 9 here has trash from 1850 down to about
1840 and lower. I mentioned something to him, and one of his buddies with a
bandscope (and who reported an S9 noise level) checked his bandwidth for
him.
My noise level is S1, the stuff that takes up 20kHz + and - bothers me. He
buddy had S9 noise, and so reports him "clean as a whistle" on a bandscope.
By the way his trash hardly rolls off in level as I tune down or up from his
frequency about 10-15kHZ. If he was only 10kHz wide at the same levels, he
would be little problem. Since the garbage goes out seemingly forever, he
has very unreasonable signal quality.
73 Tom
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