Viking Valant 2

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KE7KPB:
I was doing a tuneup on the old girl and I had the the meter switch on plate. Hit the manual switch and the meter pegged and the front 866 started sparking. I then did a replacement of all of the electrolytic caps. Still have the issue.
i have not changed to 10k resister in the vfo as of yet. Would that be the cause? 

DMOD:
Did you receive this unit recently or have had it for some time and it worked previously?

Remove the 6146's and test them in a conductance tube tester. You may have a shorted 6146 because you are drawing some major current.

Another problem in these rigs is the Clamp tube circuit V8; either the tube goes bad or this stage is misadjusted.

http://bama.edebris.com/manuals/johnson/valiant2/


Phil - AC0OB

KE7KPB:
Thanks, I will check it out. I get to use my Hickok 539c. I will keep you informed.
The transmitter has sat for 50 years so that is why the cap replacement. It did tune up for a short time.

N1BCG:
One safe way to begin the testing is to measure the resistance of the HV supply (but first with the rig off, unplugged, and a shorting wire connected between the plates of the rectifier tubes and chassis for 10 seconds).

After it's been assured that any stored voltages have been removed, check that and the resistance between the RF 6146 plates and the chassis.

The result should indicate if you have a supply failure such as shorted cap, broken insulation, bad transformer winding, etc.  If it looks reasonable, assure that you have proper bias at the RF 6146 grids (-70 VDC). This can be done without turning on the HV supply.

w8khk:
Quote from: N1BCG on October 10, 2017, 11:02:07 PM

One safe way to begin the testing is to measure the resistance of the HV supply (but first with the rig off, unplugged, and a shorting wire connected between the plates of the rectifier tubes and chassis for 10 seconds)

I am not sure it would help to short the plates to ground.  More effective to short the filaments of the 866s to ground.

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