It's true that a mistuned amp can generate plenty of harmonic energy
content. Many years ago I was running a 76PA into a resonant but extremely
narrow banded 160m antenna. There was a contest going and so I was bumping
around the band. You get tired of tweaking the knobs in that case so I just
backed off on the power and ran around the bands roaming a frequency that
covered roughly 3:1 or less SWR match. Over the following week I collected
an OO card and a few FYI email from guys nice enough to mention that my CW
2nd harmonic was being copied in the low end of the SSB 80m band.
I've moved since then and have better antennas. But a feature of all the
new stuff is a notch on the 2nd harmonic if it's in a ham band.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message-----
From: Steve Wright
Sent: Tuesday, November 07, 2017 12:03 PM
To: amps@contesting.com
Subject: Re: [Amps] Alpha 87 (not 87A)
On 08/11/17 07:00, Jim Brown wrote:
On 11/7/2017 9:44 AM, Steve Wright wrote:
People seem to visualise all this heinous crap coming out of their
antenna and taking away everyones' rights, but I challenge any person to
furnish any sort of valid complaint regarding any harmonic. And I mean a
COMPLAINT, not someone three doors down being able to detect your 3F.
It is a serious mistake to view harmonics as the only product of
distortion. Any mechanism that produces harmonics will also produce
intermodulation, which shows up as clicks on CW and splatter on SSB. They
are two heads of the same snake. We can kill harmonics by filtering them,
but we can't do that with IMD.
It's an even more serious mistake to overtly self-police when there are
no issues to fix.
FURNISH THE COMPLAINT.
S
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