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Old May 2nd 13, 07:02 PM posted to rec.radio.amateur.boatanchors
Richard Knoppow Richard Knoppow is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 527
Default DX-100 or Apache?


"Scott Dorsey" wrote in message
...
Roger wrote:
Another possible choice is the Johnson Viking I and II.
Both 100 watt
rigs that cover 160m but require an external VFO.


There are literally hundreds of different transmitters out
there that will
fit the bill, and to be honest a lot of them are much
better made than the
Heathkits which always seemed kind of marginal to me.

Everybody from Hallicrafters and Globe King on up to
Collins made something
like that.

I have to say, though, that the Vikings are really hard to
beat. They are
steady as a rock, the power supply is seriously
overdesigned, and they are
well-cooled. There are hundreds of small shortwave
broadcasters in South
America using the things with the key down 24 hours a day
with no rest, and
they just run and run. Audio quality is superb. You can
add a modern
synthesized VFO or the original Johnson VFO (which is
pretty stable) or
a crystal.
--scott


The complaint about some of the Johnson transmitters is
mainly from people who want hi-fi AM broadcast quality.
Most of them have clippers built-in and filtering for the
clipper and to tailor the frequency response for best
intelligibility. This IMO is actually a plus. Without a
clipper or some other form of amplitude limiting the average
modulation level for speech must be quite low. One other
problem evidently is that if too much clipping is used its
hard on the modulation transformer. Valiants are reported to
have this problem more than the 500. In any case it doesn't
take much clipping to increase average modulation
significantly without excessive distortion. Not too many AM
rigs had clippers in them, Collins did in the 30K and KW-1
but not the 32A series.



--
Richard Knoppow
Los Angeles
WB6KBL