> - or else they blame the amp, and it shuttles back and forth >uselessly
>to the manufacturer.
Yes that's correct, since at the exciter power level everything may seem
fine; a tricky situation. I was lucky enough to work a friend not long
after I got back on the air who told me I sounded as if I had a little bit
of rf feedback in my audio when I was operating with 100 watts. An honest
report can be a real favor. Too often I hear hams being told they sound
terrific when in fact, they don't. It's a big help to listen to yourself on
a separate receiver and work someone who can make a digital recording of you
and play it back or send it to you as a file so you can hear yourself.
Fortunately there are more and more stations out there able to do that.
>Part of the difficulty is that RF feedback can be a threshold-type >effect,
>and if the stray currents are below a certain level they may >not be
>noticeable. This makes it very easy to conclude that you >don't "need" any
>precautions. But in some situations it only needs a >few dB increase in the
>power level, and suddenly RF feedback is >running riot.
>>Others operate with fuzzy audio not knowing they have a problem.
>Bob Heil certainly finds that's so. In his business a lot of people >bring
>him their TX audio problems, and he finds that most of them are >due to
>un-diagnosed RF feedback.
Interesting. I did not know that.
Rob Atkinson
K5UJ
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