Carl - another possibility I encountered using a
solid-state amp in a mobile application -
You might be getting harmonics on the coaxial line when the
amp is working. The harmonic content will not see a match
at the antenna, and will ALWAYS give you the mysterious SWR.
Now comes the question about what to do about the
situation.....
73, John K0KHZ
To: <amps@contesting.com>
> Date: Sat, 17 Mar 2001 05:24:05 -0500
> From: wb8jkr@juno.com
> Subject: Re: [AMPS] swr
>
> Carl,
>
> I think what you're seeing here is the poor forward-
> reverse isolation of the bridge circuitry. Its simply
> rearing its ugly head under higher power conditions.
> It probably gets worse as the frequency increases as
> well.
> I would suggest the readings are more meaningful using
> just the driver and leaving the amp off for any swr reading.
>
> 73, Mark WB8JKR
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