[time-nuts] Re: 5061A HV Supply, et al. {External}

[Jim Muehlberg]

Update:Â  After tearing into the A18 and finding nothing obvious, poking 
prodding and testing, it decided to start working.  I hate it / love it 
when that happens.  I suspect a clearance issue as when I reassembled it 
I could hear it snap.  So I left the cover off.

Voltage at pin 4 is 4.4 unloaded and about 4 connected to the tube.  In 
"CS Off", pump current is 1 on the scale.  Switching to "loop open" or 
"operate" causes the meter to peg and pin 4 goes to 0 or less.  Return 
to CS off, and the power supply recovers in about 20 seconds to about 4 
volts.

I'll leave it on over the weekend and sort through the embers on Monday.

Jim

On 2022-11-09 11:07 AM, Jim Muehlberg via time-nuts wrote:
> I've recently come into possession of a 5061A.  It is claimed that the 
> tube is exhausted, but I'm unwilling to scrap it (horrors!) yet. I'm 
> not well equipped for HV measurements, but it appears the +3500 V 
> supply is not working.  So, I'm hoping the tube just needs to be 
> pumped since it hasn't been powered for years.  Also missing the A3 
> assembly, but I'll worry about that later...
>
> Anyone willing to part with their A18 or loan it to me?
>
> Thanks!
>
-- 

Jim Muehlberg
Senior Engineer

National Radio Astronomy Observatory
ngVLA Local Oscillator Lead

1180 Boxwood Estates Rd B-111
Charlottesville, VA 22903-4602
P 434.296.0270
C 434.422.2017