RCA BTA1S conversion to 80M?

[Ed-VA3ES]

Hello all.     
I have moved my RCA BTA1S over to Mike, VA3MPM’s  station where he  will operate it.  He has the real-estate to run a   1 KW rig,  where I, living in a congested urban location, cannot. 

So, I’m appealing to those who know this transmitter,   if you can  give me  some pointers on conversion to 80M?   I know  I need to swap out some big micas in the output  but what else is involved?

[Ed-VA3ES]

This  is  actually more of a generic request  about RCA transmitters in general, particularly the BTA1 series, (both R and S). 

Specifically, I need to know not only which micas to swap but also the technique to resonate the final tank, without high voltage present.

[KB2WIG]

"Specifically, I need to know not only which micas to swap but also the technique to resonate the final tank, without high voltage present."

For a quick check, i'd try using a GDO. It would put you in the ball park hockey rink.

klc

[VE3AJM]

Check you email Ed. Sent you some information on this.

Al VE3AJM

[Ed-VA3ES]

Check you email Ed. Sent you some information on this.   Al VE3AJM

Got it all, Al.  Thanks!

[Ed-VA3ES]

"Specifically, I need to know not only which micas to swap but also the technique to resonate the final tank, without high voltage present."
For a quick check, i'd try using a GDO. It would put you in the ball park hockey rink.   klc

That will ballpark it, certainly.  The  usual technique is to  disconnect the B+,  then  replace the PA tubes with a resistor equal to the plate load and run an antenna analyzer ‘backwards’ into the tank and then tweak pi-net  for lowest SWR.   Remove the resistor, replace the finals,  run B+  then  do  a final dip.

I will   experiment with different  (smaller) values of C until I can resonate the tank on 80.