[Collins] KWS1 Problem -- No HV Comes on

[Wally Klinger]

Hi All:

 

Trying to get a KWS1 back on the air.  The Plate HV will not come on.  No red indicator light indicating that the HV
is on, nor is there any buzz coming from the transformer. 

Checked all the fuses and the RF cage interlock.  All OK. 
 

So far, I have checked continuity from Pin 3 of TB501
through the interlocks, jumered the interlocks just to prove them okay, through
the plate switch, up to the K501 contactor. 
I get resistance across the coil indicating that the coil is not
open.  But no voltage on the coil.   I
swapped the time delay relay, and even jumpered over pins 5 and 7 to see if it
is the time delay.  I have voltage on
pins 2 and 7 of the time delay and the fan is running.  I have voltage across pins 11 and 12  on TB502. 
I pull the wires off the K501 contactor and I get no voltage. Regardless
of where the emission switch is set. 

In the RF deck I checked continuity from pin 7 on J103 all
the way through the RF cage interlock switch. 
All OK.

 

Is there anything else that would cause the HV circuits not
to come on when the plate toggle switch is on and all normal conditions in the
transmitter are met (interlocks, cabling OK, filaments on, fuses good, etc)? I appreciate any guidence that the list might have to offer. 73--Wally W9BEA