Bill,
I have experienced several such cases of fellow hams blowing crud all
over a band, and "not hearing" those who report the problem. But most of
the offenders I have heard are operating factory-made equipment! Very
often they use a 100W radio to drive an amp that needs 50W or less of
drive, and don't connect the ALC line. Radios with slow-acting ALC are
also famous for causing IMD blasts and key clicks without even needing
an amp, and there are many. But the most usual way of producing lousy
signals is by intentionally defeating the ALC of the transceivers. In my
environment they call it "liberating" the radio, because the poor radio
was tied down to just 100W by the evil manufacturer, and by defeating
that "brake" it can produce 150W or so, when turning the mic gain to
full and then screaming into the mike, right?
I try to gently educate such fellows whenever I have an opportunity, but
many simply don't want to listen.
Sometimes radios develop faults that make the transmission dirty. I
remember a case of one station running a factory-made radio with a bad
PLL. It had an extremely high phase noise, and would transmit modulated
noise over a wide part of the band. That guy did reply to my report, and
told me that he had the same very high noise on RX, so he thought that I
was hearing what he thought was his local noise floor! I tried to
explain to him that probably his radio was faulty, and I went on to
explain about phase noise in frequency synthesizers and how that can
affect both TX and RX, but he totally rejected my suggestion that his
radio was faulty. He replied that his radio was putting out "the full
100 watts and some more", and thus couldn't possibly be faulty...
There is a ham a few hundred km from my place who runs a homebrew PWM AM
transmitter, with the pulse width modulator running at 20kHz. Apparently
his transmitter doesn't have enough filtering after the PWM stage, and
the result is that I can hear him loud and clear every 20kHz, all across
the band and beyond... And he has never replied to any of my reports
about it.
Lids are everywhere, and also new hams who try to do things right but
just do beginner's mistakes. Personally I'm very apt to forgive someone
who is testing a homebrew rig that turned out to be dirty, while I have
some trouble forgiving those who defeat the ALC of their radios. But of
course any ham who gets a report of causing interference should listen
to it, acknowledge, and do his best to fix the problem.
Manfred
This privilege is a double edged sword. About ten years ago I was
operating during a RTTY contest on 40 meters when I noticed a fairly
strong blast of white noise all across the band. The noise came and
went with a rhythm that suggested someone calling CQ. Long story
short, it turned out to be a fellow on the east coast of the US who
was using a homebrew class E amplifier. He would not answer me on the
air so I sent him an email after the contest was over. Never heard him
again.
Such transgressions are rare but they do happen.
73, Bill W6WRT
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