[Johnson] Viking Thunderbolt

Steve H teknoskillz at comcast.net
Thu Feb 4 12:43:05 EST 2021


Making more progress today.

Rewired the terminal strip and now all the
heaters in the amp come up when you throw the toggle switch...as well as the
cooling fan in the final tube area. I didnt run it for long as I was told
that fan needs to have the bottom cover on at all times for air flow design,
as even at idle, the filaments need that cooling going on.

I wired in a seperate switch to the plate relay in the KS-1 in lieu of the
soft start circuit for now. Also plugged the 220V recepticle into the wall
for the first time ever since they put the wiring in the wall, and I threw
the switch to the plate relay with my HV probe on the DC output line. The
relay banged into operation and the meter read 3486 volts dc. I did not have 
it
hooked to the Thunderbolt. When I opened the switch, the meter gradually
went down to 0, so I know the bleeder array in it is working ok.

Also started wiring up a ground wire from the KS-1 which will go to the
chassis of the Thunderbolt, and also eventually to my station ground.
I am told if I left them seperate, it would be a "death trap" so I want to 
avoid that
for sure.

One question regarding the output tank of the Tbolt, I was told its got an 
ample
tuning network and an external tuner may not be needed. I have a Dentron 
MT-3000A
antenna tuner that can handle I think 3KW. My antennas are already on that 
as its got the selector
switch. I think if I leave that in line, I will be tuning the radio, then 
the amp, then the tuner, which is
redundant. Is there a better way?

--
Steve Hearns
KA2PTE





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