[Amps] SS vs. Tubes (was "I gotta tell this")

[Vic K2VCO]

Peter Chadwick wrote:

> The mechanics of the cooling of the SS amp, plus the low voltage, 
> high current  wiring and PSU, make the kW SS amp a bit more 
> complicated than the tube amp, at least to my mind. The overall 
> efficiency is no better, the flexibility to handle high (up to 3:1) 
> SWR requires a built in tuner, which at low impedance can lead to 
> awkwardly higher capacitances on variables unless the impedance is 
> stepped up, all suggest that for home brewing, tubes are easier. 
> Forgetting, for the moment, costs, of course.......

Everything that you say is true, but given that one wants near-instant 
band-change, it's much less expensive to match your antennas to less 
than 2:1 and go solid state (no built-in tuner needed) than it is to 
build or buy an automatically tuned tube amplifier.  And I submit that 
it's probably less expensive to build a solid state amplifier *with* a 
built-in tuner than an automatically tuned tube amplifier.  We'll see 
about this if and when the Elecraft solid-state amplifiers are finally 
released.

> And we don't frequency hop that fast - not even in the SS contests!

Well, I do.  There's one particular contest that I'm interested in where
this is useful.  And in these days of telnet clusters, you have only a
few seconds to work a DX station before the pileup develops.

I've owned both a fine, legal-limit, manually tuned amplifier (with a
3-minute warmup time) and an unstable, fragile, 750-watt solid-state 
amplifier.  My operating style caused me to favor the solid-state 
amplifier.  I probably would have been happier with an Alpha 87 or Acom 
2000, but then, who wouldn't?
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco