[Amps] Henry 2K-2 failure

[Mark - N5OT]

Thanks Vic.

What has me scratching my head - why would it flash with no drive, just 
idling, with the event triggered only by changing the T/R relay from 
transmit to receive...?

(I suspect I am showing my ignorance).

Thanks - Mark N5OT

On 9/6/2024 12:01 PM, Victor Rosenthal wrote:
> Just guessing, but you may have had a plate-grid flashover, which blew 
> the plate meter and then damaged something in the grid/biasing circuit. 
> Zener or capacitor perhaps?
> 
> Victor 4X6GP
> 
> On Fri, Sep 6, 2024, 15:49 Mark - N5OT <r-emails at n5ot.com 
> <mailto:r-emails at n5ot.com>> wrote:
> 
>     Greetings.
> 
>     Today I have a 2K-2 that has developed a problem.  For grins / out of
>     curiosity, I thought I would see what I could get out of a pair of used
>     Eimac Y-826s that had tested good some years ago.  After I tested
>     them I
>     wrapped those tubes up and put them on the shelf waiting for the right
>     moment.
> 
>     The amp ran fine for maybe 2 hours on CW at probably 25-50% duty cycle.
>     I was surprised how much drive was needed - really the tubes performed
>     no better than the 3-400Zs I took out and set to the side.  Oh well.
> 
>     When I was doing some additional testing the following happened:
> 
>     1. The little red breaker popped when I let up on the footswitch. 
>     So it
>     happened during a non-key-down moment.  I let up on the footswitch,
>     heard the click, amp now did not transmit.  Checked breaker - it was
>     popped so I reset it.  Amp now worked again but plate current meter no
>     longer works.  Yes, I know I should have protected it.  I am
>     assuming it
>     was not protected.  Oh well.
> 
>     2. Amp transmits just as it did, however, now the tubes glow orange
>     100%
>     of the time, even while idling at key-up.
> 
>     I am assuming this is not a sustainable condition, something changed or
>     broke, and I need to not run it like this.
> 
>     I am also assuming there are multiple smart guys reading this who know
>     from the description above what has happened and can guide me toward
>     restoring the amp to operation.
> 
>     Learning by experience,
>     73 - Mark N5OT
> 
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