Just to prove I really am still working on this I thought I would post and update. I have all but two of the caps that I am planning to replace done. I also replaced the output tube grid leaks and a coupe of cathode resistors along with the PS filter resistor. One of the wires to the dial lights was disintegrating so I replaced that as well.
I disconnected the can cap and cut off the soldering lugs. I used an existing hole in the chassis to mount a new ground lug for the PS caps and a plastic mounting strap that I put underneath. Then I drilled out one of the rivets on the old can cap and replaced with a screw and lock nut to mount a terminal strip for the PS cap connections.
The lock nuts that I got (integral star washers) for mounting the loose sockets would not fit underneath as there was not enough room between the screws and the socket body so I put the screw heads underneath and the nuts on top. I figured that shouldn't be a problem since nobody sees the chassis. I did notice that the plastic base of the tube hits them before it is fully seated. It only holds the tube up about a mm or so. I am hoping that this is not a problem. If it is maybe I can grind the nuts down thinner.
There is a grid resistor (R51 below) on the first audio stage tube that is supposed to be 10M but it measured 11M. I had C14 removed at the time that I took the measurement. At first I thought that the series combination of R41 and R42 should have shown up in parallel with it but as I look clooser at the schematic the top of the "22" just makes it look like there is a connection there. I left that resistor in place as it was a little hard to get to. Do you think its being about 10% high like that will be a problem? My 7B6 data sheet does not give a max grid leak value.
Thanks for your interest.
mike
09-26-2009, 06:13 AM
Hybrid Mode
