[Elecraft] Solid State Amps

[G. Beat]

Lee -

Just a couple of additional points - that Jim, N2EY did not mention in his 
very good reply.

1. Glass RF tubes ( 811 / 572B, 3-500Z) are no longer manufactured in the US 
in large quantities. Eimac and other mfg. moved to ceramic RF tubes and sold 
off their glass tube production.
Russia, Eastern Europe and China have the majority of the glass RF tube 
production -- which you can see at RF Parts.
The quality of glass tubes has also become a concern -- I regularly read 
stories of 'bad Chinese tubes' , Svetlana 572B with smaller plate areas than 
other 572B tube mfg., etc.

2. Sweep tubes are at End of Life (EOL).  There are conversions to EL509 or 
EL519 Eastern European TV sweep tubes --- but it is still a sweep tube!

Due to these 2 points many previous amplifier owners are looking for 
something that is "easy of operate" and "works"  --- without having to worry 
about parasitic suppressors, and religious debates since 1990 about problems 
with some glass tube amplifiers.

Lastly, the new 8877 designs, such as the new Alpha are not cheap and have 
exceeded the pocketbook ($$) of many hobbyists.

w9gb

----- Original Message ----- 
From: "Lee Buller" <k0wa at swbell.net>
To: "Elecraft Reflector" <elecraft at mailman.qth.net>
Sent: Friday, June 01, 2007 9:01 AM
Subject: [Elecraft] Solid State Amps


>
>
>
> When I attended Dayton this year and reading the magazines, I see there is 
> now a great interest in solid state amps.
>
> I thought that these amps were...well...not as efficient as tube amps thus 
> not being attractive to hams.  I guess we wanted BIG iron for an amp.
>
> Ameritron has two amps out for quite some time...the 500 and 600 with the 
> 600 now coming with a switching PS.  It seems people who own the 600 watt 
> model like them very much.
>
> Even "E" has the contesters contest amp and it is solid state.  So, what 
> has changed?  Have the SS Amps gotten more efficient?  Higher voltages? 
> What effects the efficiency of these amps where now there seems to be a 
> market for the Japanese and the Italians.
>
> Now most radios provide 100 watts output using transistors and the tube 
> finals in rigs have long been gone.  So, is this just a natural evolution 
> of amplifiers or is some new technological breakthrough happened in high 
> powered solid state amplifiers?
>
> Lee - K0WA
>
>
>
> In our day and age it seems that Common Sense is in short supply.  If you 
> don't have any Common Sense - get some Common Sense and use it.  If you 
> can't find any Common Sense, ask for help from somebody who has some 
> Common Sense.  Is Common Sense devine?
>