RE GS 35 B Possible choice for Homebrew Amp:
Thanks Bill for your comment on the GS-35B The efficiency may become
important, if it means that you cannot get 1.5KW out of the GS 35B with 100
watts drive. Whether the efficiency sucks more watts out of the wall
socket/power supply is less important than if we can get full output with a
solid state 100 watt TX exciter.
Some more questions about the GS35.
Are all about the same reliability, independent of source? what percentage
random DOA? Best purchase source? USA dealers? Eastern Europe hams? New?
Used? NOS? I have seen suggestions for conditioning which recommended all
newly acquired GS 35bs be operated at reduced B+ and heated for some time to
Getter out any residual gas.
before applying full B+ for operations.
One of the first GS 35B Amps I looked at some years back used very simple
clamps of the grid ring directly to the chassis, with a hole punched for access
to the cathode/filiment power. Almost no "Socket" per say. And simple
drilled holes around the base to allow cooling air to be chimnied. or ducted up
through the anode cooler fins.
Also I recell a lot of backpressure, and flow reqts to the tube. Is a GS 35B
amp properly cooled, noisy, esp when compared to a typical 3-500Z pair which
requires far less pressure to get the flow?
Also on a more practical level, I plan to ship various KW RF components, for
this project, to Uruguay, proabaly only the lighter ones...chokes, tubes, band
switches, meters, etc. What is the best (Cheapest) choice for an
international shipping company between USA and Uruguay?
Thanks to those who have replied to earlier queries about sourcing the QRO
power supply pieces. I am hoping to find a sympathetic Radio Station engineer
in Montevideo, or Salto, that may source a suitable, surplus to their use,
B+ transformer.
Thanks guys,
Best Regards,
73, de Pat Barthelow AA6EG
> From: dezrat1242@yahoo.com
> To: amps@contesting.com
> Date: Tue, 27 Apr 2010 09:20:46 -0700
> Subject: Re: [Amps] Helping a Uruguayan Ham build an Amp.
>
> ORIGINAL MESSAGE:
>
> On Sun, 25 Apr 2010 10:15:47 -0700, Patrick Barthelow
> <apolloeme@live.com> wrote:
Then even the possibility of choosing a GS 35B tube as as the basis of the amp.
>
> REPLY:
>
> I would recommend against using a GS-35b. Their efficiency is low
> compared to other types. I and several others have obtained
> efficiencies in the range of about 50%, compared to about 60% for an
> 8877 and other comparable tubes.
>
> Aside from poor efficiency they do seem to work well so that is not
> necessarily a show-stopper, just something to consider.
>
> 73, Bill W6WRT
_________________________________________________________________
Hotmail is redefining busy with tools for the New Busy. Get more from your
inbox.
http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_2
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|