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Old April 8th 07, 03:37 PM posted to rec.radio.amateur.homebrew
Dave Dave is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 108
Default simple(?) question...


"Bob Liesenfeld" wrote in message
...

"Dave" wrote in message
...
Hmmm. Okay, well, could the problem be the monolithic ceramic caps I
used? Something is creating a boatload of harmonics, and that's the only
other component besides the transistors themselves.

Thanks much for the input...

Dave



Hi Dave,
This post mentions something that I did not perceive from your first
post. You mention a 'boatload of harmonics". As I understand it, the
MFJ-1020A is an active antenna circuit, but I don't have any details.
How are you noticing these "harmonics"? If you are hearing them from the
receiver this circuit is feeding, my guess is that either the active
antenna or the receiver front end is being overloaded and driven into
non-linearity. I would suspect the active antenna.
Can you provide more information? Where are you located, urban or rural?
What kind of system is this circuit a part of?

Bob


Hey Bob,

I am feeding a signal from my RF signal generator to the circuit on my
workbench. I mention harmonics because the sinewave goes from nice and
clean to "blurry" and looking "smeared" across the screen of my O-scope. I
may *be* overloading it, but I thought that would result in clipping of the
waveform. I have the signal generator set to attenuate the signal severely,
and *thought* that would prevent overloading. Maybe not...

Back to work on it some more, and try to make sure I am not overloading the
device.

Thanks,

Dave