[Amps] GS-35b

[MIKE DURKIN]

Well -- she went BANG!!!! today .... and frankly its about time !!!!

Another lesson remembered - never work on equipment when your tired. I for some reason (tired) used a insulating washer on the tube side of the plate blocking CAP. I really don't know why it even worked in the first place, since there was no large area contact from the Anode strip to the blocking cap ..... luckily i saw where the flash was and when i peered behind the blocking cap on the tube side i could see the problem and felt a numbing sensation of "how could i do something so stupid" HI HI !!!!

Time for some more testing but she's putting out 1kw on 10M right now (1.5Kw on 20) ... having an odd change in input SWR (on 10 it look like) now at first key ... low then goes to about a 2 then drops back down .... odd.

KC7NOA
From: 
To: patriot121 at msn.com
Subject: RE: GS-35b
Date: Wed, 8 Sep 2010 23:35:55 +0000
















Only
ever had one fail on me, the tube flashed over and kept flashing over, taking
out the HV fuse.

 

Problems
with low power, but high anode current were a sign of a control problem. I use
the GM3SEK control board and initially, there were problem with the TIP147
device failing, and when it did, I had high anode current and about 500w out,
but zero drive and zero PTT.

 

Even
after such a failure, once the TIP147 device was replaced, the tube performed
OK again.

 

Are
you sure it’s the tube that’s failed?

 

Another
idea is that with reduced power out, yet drive is OK and anode current ok, it’s
possible that the amp is now ‘off tune’ some how. Maybe something
has failed?

 

Further
investigation is required by the sounds of it…

 



73,

Andy

http://gd0tep.com



 





From: MIKE DURKIN [mailto:patriot121 at msn.com] 

Sent: 08 September 2010 22:53

To: andy at gd0tep.com

Subject: RE: [Amps] GS-35b





 

Yes
.. did you ever have a GS-35B fail on you .... ??? what were the signs ??
sudden power drop off but still dawing current with drive ??



Mike

KC7NOA



> From: andy at gd0tep.com

> To: patriot121 at msn.com

> Subject: RE: [Amps] GS-35b

> Date: Wed, 8 Sep 2010 21:40:24 +0000

> 

> Hi Mike,

> 

> Are you talking about the copper anode cooler?

> 

> 73,

> Andy

> http://gd0tep.com

> 

> -----Original Message-----

> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On

> Behalf Of MIKE DURKIN

> Sent: 08 September 2010 21:07

> To: amps fourm

> Subject: [Amps] GS-35b

> 

> 

> Any one know how to remove the heat spreader from the triode (gs35b) ??

> 

> Mike

> KC7NOA

> 

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