>> 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.
>
** A too familiar story, Tom. One morning about a week after the
Challenger "anomaly", I ran across an 80m guru by the name of Roy Neal
(the science advisor for NBC). Roy was driving a solid-state amp with
about 70% watts more than the rated drive spec., and I could hear his
splatter up the band 10KHz more than normal. I broke in and told him
what I was hearing. He said it was probably because his radio had more
drive than the amp needed. The other guy Roy had been talking to said
that he had checked Roy's signal and it "completely dissappeared when he
tuned 500Hz higher".
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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