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Old July 15th 05, 09:27 PM
xpyttl
 
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"Roy Lewallen" wrote in message
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Joeseph wrote:
, , ,
Assuming you are correct my next problem will stopping the extra
frequencies from getting out of the amp in the first place.


No, your problem should be figuring out how to prevent them from getting
generated in the first place. If the harmonic or spurious content is that
high, there's something seriously wrong.


Nice answer, Roy. That was my knee-jerk, too.

Joseph, remember, the problem isn't only "stopping them from getting out of
the amp...". Those other frequencies are some sort of parasitic in the
amplifier. Besides being stuff you don't want going to the antenna, they
are robbing your amp of the ability to amplify the frequencies you DO want
amplified, and they are unnecessarily heating up your transistors and
sapping their life.

So first, keep them from being generated, then stiffen up that low pass
filter so anything that does get created is way, way down. Far lower than
what will show up as an apparent SWR problem.

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