Peter (SM2CEW) and others have raised some interesting points about "dirty"
SSB signals heard during a contest this weekend. The topical points this
raises are interesting.
I'm certainly personally an adovcate of having a good, clean signal. The
problem is, I don't know how to do that without resorting to asking for
on-the-air signal reports, which, fortunately, I get every day I'm on the
air through guys on the net I check in with. Let me explain why I otherwise
don't fully know what kind of signal I'm putting out.
I'm sitting here with a nice matched exciter, final, and monitor scope.
WOW! What more could a guy want, you say??? Well, believe it or not, I
still don't know of a way to tell the composite quality of my transmitted
signal.
Yes, the exciter and final are hooked through the monitor scope. So what
does this do for me? Well, in one switch position, I can look at Sine Waves
dancing around over the screen of the scope. These fluctuate in width and
amplitude with speech, and vary so fast that I really can't tell if I'm flat
topping or not. The other test I can run is to use the oscillator in the
scope to inject a two tone audio signal into my rig and then look at a
trapezoid screen pattern. This test does indeed tell me if/when my final
isn't behaving in a linear manner. But, it is only useful with the tone
injection, and doesn't tell me anything about transmitted signal width
and/or buckshot/splatter when speech is present. It tells me what the final
is doing in a steady state condition.
So, given the above, is there any simple, practical way of getting a good
idea of what kind of signal my rig is putting out? I have a feeling there
may be a fair number of hams out there who would like to know the answer to
this question. Please keep any answers as non-tech as possible. I'm sure
that by now the 8,000,000 or so hams reading the mail on this reflector have
figured out that I'm not a rocket scientist or brain surgeon by profession
or training.
I don't want to ever put out a bad signal. I'm thankful that I have a
means, through other hams on the net I check into, to give me a reading of
relative signal quality. Is there a better way?
73 de Ron, K5BDJ
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