At 07:55 2000-03-06 -0700, Rich wrote:
>>Checking the web pages out shows these stations run FT1000MP's, FT1000D's,
>>TS-950's, Alpha's, Henry's, you name it.
>>
>Peter - 'This has got to be an amplifier adjustment problem. The radios
>you mentioned are fairly clean.
>
>cheers.
This is what puzzles me, but there is no doubt that "fine" radios can turn
into mean machines if they are improperly adjusted. Many of the signals
heard over the weekend had the sound to them that you get from setting the
bias too low. I suppose this could be in either the exciter or the
amplifier but it must be the easiest thing to check for most amateurs. Then
again, one would have to find out what the ZSAC should be..
I have been making some test with a good friend of mine re the behaviour of
the FT1000D when driven beyond the ALC top level. IMD products 3.5 kc away
from from the ssb carrier frequency rises about 10 db just by letting the
ALC needle swing a little higher than recommended. This test turned out
equal on two FT1000D's, driving different types of amplifiers. There is no
doubt that even the FT1000D needs full attention not to sound bad.
Listening to the microphone freaks on 14178.00000 in the mornings will tell
you that the TS950SDX will splatter, check "Your Friend's" signal out and
you will hear quite a lot of hash down the band. And they think they have
the best audio achievable on SSB. Well they might (if you like the sound
and want to spend 10.000 USD on a mixer/microphone), but out of the
passband there is trash. Trash that their friends who want to operate close
to the frequency will have to listen for NO reason.
So Rich, it could be the amps, it could be the transmitter, but I'd go as
far as to say it is the transmitter that makes the signal sound bad in most
cases. (Or should we say the combination, to be politically correct..)
Ciao,
Peter/SM2CEW
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