----- Original Message -----
From: Steve Lawrence <smlx@earthlink.net>
To: <amps@contesting.com>
Sent: 16 November 2002 07:19
Subject: [Amps] LP filter effects
> I have an old Drake 1KW LPF in line running 1500w output from an Alpha 87A
> to a TH7DX. It's worked fine for several years. I've pulled the LPF out of
> the line. At 28000 with 1500W out, the reflected power dropped from 200 to
> 100 watts. There is also an improvement on 20 and 15.
>
> Comments appreciated.
Assuming the power meter is between the LPF and antenna, it's difficult to
see how the LPF could be increasing the harmonic level. Another possible
cause is that your meter has poor directivity and heightened sensitivity to
harmonics. I'd say that's much more likely.
Steve
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