Thanks to the help here, the set is done and playing very well.
I did transfer the transformer over to this chassis, as this one had a fire in it, that probably was a electrolytic gone bad, and set left plugged in. I know it was a decoration for many years in a dead state. Interesting to me that the junk chassis had much more rubber wiring than this one. This one has more cloth than rubber in it, and appeared unmolested, save for the burnt xformer and wires to it.
I learned how to replace caps and the electrolytics, but confess there are 3 caps left I just cant quite get to near the antenna. One is under the tuning switchboard. I'm not that desparate to move it off. I did so on my junk chassis to see what it would take. It is at least 7 connections and you have to extract the switch assy out. Not for me at this time. Interesting aside, on the front of the switchbutton bar to the front where it cannot be seen is a build date of the set itself. The junk one was June 2, 1941. You could only see this, if you pulled it out of the chassis.
It did get an inline fuse, and a repro escutcheon. Much better than a shrunk original.
So here it is, and the pushbutton tuners work, and hold the station nicely. No funky noises, hum or crackling.
Thanks again folks!!
Mike
(This post was last modified: 09-02-2014, 07:52 PM by standardtwin.)
More often then not you can gain access to the capacitors and resistors mounted above the pushbutton assembly without removing the assembly. In some cases you can remove just enough wires to allow you to loosen the assembly and flip it out of the way. I will have to examine the circuit to see if any of the capacitors in that section may cause a catastrophic failure, like a bypass capacitor between a plate or screen grid and ground.
Regards
Arran
Thanks all for the encouraging words, much apppreciated!!
The caps are #24, 27 and 30. The drawing is misleading, as #24 is much farther under the board than shown. It is not possible to get to, unless you completely undo the pushbutton assy. I took apart the junk chassis I have to verify how its done. It's at least 13 connections, plus the wires up to the tuner assy through the chassis. Looks like its part of the XXL and 7B7 tubes. 27 and 30 are a probable to do, although 27 is really tight. There is one under the oscillator coils, that I was able to do, as that can be lifted carefully out of the way without undoing anything.
I just wasn't real keen on removing that assy. As all looked physically OK, I didn't go there......
(This post was last modified: 09-06-2014, 10:09 AM by standardtwin.)