Hi Bill and all,
> The key clicks seem to be getting worse and worse. This year in the
> CQ 160 contest, there was one station who could be heard most of 5KC
> with his FT1000D. Several others using Yaesu radios were also
> producing really poor signals. The same thing this weekend, although
> I'm not as familiar with the radios that most Europeans are using.
I've been watching this for a while and keeping a list, and it isn't
just the MP's that are problematic. The 775DSP's are particularly
bad for spurious signals, thumps, and clicks.
It also could be amplifier turn-around-time at work with any rig. The
TX relay might not be closing fast enough. Some QSK amps
actually use regular mechanical relays (not even vacuum relays) in
TR switching. Vacuum relays are marginal enough for QSK, but
conventional mechanical relays (even small enclosed relays) are
pathetic for QSK. You can be sure they are closing while the RF is
applied.
Amplifier loading is likely not a problem. If it is, it is a self-
eliminating problem because the HV in the tank will be so high
(from underloading) that eventually the op will arc a bandswitch or
some other major component.
Another problem is alignment and other defects. N7DD had this
problem with his MP, as did W8LRL and others. The 1000MP can
make a buzzing hissing clicking signal (and even have spurious
signals) if the synthesizer is aligned to factory specs according to
N7DD in a recent post to topband.
(The only saving grace is if it is far enough out of alignment, it
bothers the receive also.)
Listen on DX pileups, and you'll hear a few IC-775DSP's thumping
on the DX station's frequency even if the split is ten kHz!!! I'm
seeing more and more people complaining on DX clusters about
this, so I think the problem is getting worse (probably because
more older radios are getting replaced).
The real solution is probably just to tell the offending station.
Certainly some of the time it can be the receiver at fault, but if
many people hear and report the same problem the odds increase
dramatically it is the TX. There seems to be a mind-set today that
if you give an honest report you are being a "cop". I think that idea
carries over from Democrats on CB...where people have learned to
accept poor signals as a way of life, and saying anything negative
(even if true) is forbidden.
Measuring on commercial test equipment, I've seen plenty of rigs
that have junk up or down two kHz or more. I've never said much to
anyone, because of the "cop" retort that usually happens.
73, Tom
(W8JI@akorn.net)
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