This has been a issue since the first synthesized TX hit the band.
>From all indicators "it aint getting better".
Take a serious look at the TX waveform picture in QST....most all of our
rigs have been pictured over the past 12 years or so....at least back to
the TS930 era.
Now, look at that picture of the transmitted composite phase noise.
Next, look at those spikes on either side of the carrier. Yep, most
Riceboxes have them and they are typicallly 1.5 to 5 KHz from the
carrier. Some worse than others, some have multiple peaks. What you see
is what you hear.
Those spurs meet FCC specs and are over 50dB down, most decent rigs are
-80dB or better. But now define 50 to 80dB down from someone who is
40-60dB over S9 on your meter. Never mind that the meter lies
anyway....you will still hear that spur loud and clear from any LOUD
station and even from the not so loud guy given the wide range of
possibilities (all legal). At this juncture I wont even get into bad
phase noise rigs in general....some should be banned. Or reciprocal
issues.
What to do? Besides everyone going back to the old Collins or Drake rigs
or buying a TenTec OMNI 6...absolutely nothing. The disease is inherent
in your Ricebox along with the desire to have at least 1000 bells and
whistles that are not really needed. All that high tech garbage and
general coverage adds not only crap to your TX signal but also degrades
the RX side. Yeah, I know, its hard to degrade anything on 160M, but
many of us have a life outside of the band! ( Im now QRV up to 3.3GHz)
and synthesizer crud is a big issue.
Ask yourself....why do so many of the serious 160M ops (serious defined
as over 250 countries) use rigs or slaved receivers designed for very low
phase noise, spurs. etc.
Got to keep this short, time to gas the generator. Now 2 1/2 days
without utility company AC
73......Carl KM1H
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