[AMRadio] COLLINS KWS 1 power supply questions

Bernie Doran qedconsultants at embarqmail.com
Tue Nov 3 06:19:35 EST 2009

Hi Greg:  nothing wrong with the solid state replacements, and they DO NOT 
raise the voltage. The rectified DC is taken from the fil trans center tap, 
so you will have to rewire that lead to the socket base if you  disconnect 
the fil trans.   I would suggest that you also disconnect the primary side 
of the trans as well as the secondary side.  However, 3b28s are an excellent 
replacement and do not require any changes, maybe hold the solid state 
diodes for spares if the fil trans ever fails.  ( not likely)  There is also 
nothing wrong with the KWS1 on AM!!  only transmits one sideband, so what, 
how many do you listen to?  be prepared for some slight drifting, takes 
about thirty minutes before they stabilize.   drifting has minimal or no 
effect if you use it on AM, just keep the carrier down to less than 200 W. 
I also keep the top compartment open to let some of the heat out of it

I think I will turn on mine tonight for the CCA first Wednesday at 7PM est 
3880 or so. it has not been on for months. will use lower sideband, I always 
found it rather amusing when someone has a selectable sideband rx and they 
check the other side and find nothing.

good info on the fuse, I will get a spare, I knew that there was a run made 
some time back, but did not know they were in production.     Bernie W8RPW 

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