Run the tube at RF at half the arc over voltage and it may last a long time
and even improve.
Thats still a decent signal.
Carl
KM1H
----- Original Message -----
From: "Mike Waters" <mikewate@gmail.com>
To: "nemo zilch" <nemozilch@gmail.com>
Cc: <amps@contesting.com>
Sent: Thursday, February 26, 2015 3:30 PM
Subject: Re: [Amps] GS35B Gassy, or Arcing?
I went back and read more of that page after I got more fully awake. Forget
what I said about the 3800 volts for now.
Sometimes, high voltage applied to a tube, BUT with more current behind it
than you've applied, causes a one-time arc that clears a tiny bit of
debris
that got in during manufacture. I've personally seen that happen with some
572Bs in my SB-200.
In my case, I added a 10-20 ohm glitch resistor and AGC 1 glass fuse in
series with the HV anode supply. The first time (IIRC) that I powered up
the amp, the fuse blew. When I replaced the fuse, the amp could be used.
That fuse blew two other times, but has never blown since (in over two
years.)
You never know unless you try, :-)
73, Mike
www.w0btu.com
On Thu, Feb 26, 2015 at 2:04 PM, Mike Waters <mikewate@gmail.com> wrote:
Sounds like you received some other info off the list.
I have a wild hunch. What happens if you don't leave the grid floating?
Try the hi-pot test with the grid connected to the cathode.
And did you try this again with the filament lit?
In your OP you said you wanted to run it at 3800 volts. It's been awhile
since I researched that tube, but isn't that kind of high for the GS-35B?
http://www.gs35b.com/gs35b/
73, Mike
www.w0btu.com
On Thu, Feb 26, 2015 at 1:34 PM, nemo zilch <nemozilch@gmail.com> wrote:
OK gang. I think the collective wisdom of the group is that my tube has
more than average gas and that operating it with plate power is not
likely
to help due to the location of the getter. So, guess I just lost out in
the Russian tube sweepstakes. Well, I went in with my eyes open, so
I'll
take my medicine.
I am going to run it with plate voltage and current, probably can get
nearly 1500 Watts into it. If that makes any improvement, I'll let you
all know.
Thanks everyone for the advice, I really appreciate it.
Bob W4AOS
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2015.0.5751 / Virus Database: 4299/9184 - Release Date: 02/26/15
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|