I recently found this pair @ a very nice price ($45 at a garage sale) and
threw it in the car more on the upcoming hernia operation later. I
checked the tubes in the receiver (all good) and found that the caps had
been replaced in the not too distant past. So I hooked it up and began to
bring it up on a variac. No smoke, no fires..but no sound other than
scratchiness when I turned the volume. Haven't had much time for
troubleshooting but I did open the power supply. Seems all
original..removed the tubes and checked 'em. They check fine on my cheap
tester (Heathkit IT-17). Found some info on the net about this unit. The
RA-84-A callls for a Jan 5Z3 and a Jan 80 tube. I've got a 5Y3WGTA in the
5Z3 socket and a 5U4GB in the other. Is there a reason why someone would
swap these tubes out?? Other than the fact that they didn't have the
proper ones, of course. From the limited info I've found on the net, these
tubes don't seem to be interchangable.
Anyone able to point me in a direction that might help?? Would the present
tubes prohibit the radio from coming to life? Could the previous owner
have altered the PS so as to use these tubes?? And if so, what should I
look for in the way of alterations. It looks to be untouched, but I
haven't compared everything to a schematic--just ordered a manual today.
I'm pretty new at this and any help would be great!!