[glyphmon]

Interim test point reached.

I wanted to do this in more granular stages, but I also wasn't going to redo soldering any more than absolutely necessary.

Replacements done so far:
All (3) electrolytic capacitors, C16, C30, C31
1 paper capacitor, C32
Resistor in IF can, R5
Resistors on top of the tuning condenser, R2, R19
Candohm (R14, R15, R16, R17, R18)
6F6 and 6H6 ordered NOS and installed (missing when I acquired the radio)
Any disturbed wire with crumbling insulation has been replaced, more to come, even if I don't otherwise need to disturb it
Put a fuse on the hot side of a new polarized power cord and from there to the switched connection on the power switch

Checked for shorts and resistance on the transformer and those tests showed the expected ohms

Remaining replacements:
7 paper capacitors, C15, C19, C24, C25, C27, C28, C29
1 resistor, R13

One thing I noticed however was when I was testing the connection through the power cord to the back of the power switch (switched connection to transformer) was that no matter what position the switch was in, there was a connection, so "OFF" doesn't seem to actually cut the current.  Varying levels of ohms, but always a low, measurable amount.

So with that said, I did a gentle power-on with radio into dim-bulb into Isotap.  Ramped power up to 120V gradually, with bulb increasing in brightness, but never reached anywhere near full-bright.  No magic smoke, no fireworks, so initial win.  Removed bulb from circuit and again ramped up power to 120V again.

Dial lights came on and made it to full brightness.  Speaker was essentially completely silent, but when on close-to and full power, fiddling with the volume knob led to crackling noise while I was adjusting it, but returned to silent after.  I took this as another win because "speaker can make noise".  But that being said, absolutely silent otherwise - not even any hum.  Tuning in one direction or the other had absolutely no effect, even switching bands was silent.  As expected, the power switch (also tone control, 4 positions) didn't cut power in any position.

So, obviously I will continue on replacing the remaining paper caps that need to be done and the one remaining out-of-spec resistor and I'll test it again after that, but I'm thinking there's probably something else awry.

I've never done much voltage checking, but I suspect that's a next step for diagnostics.  Anything else I should be checking at this point?  Absent a tube tester, should I just order a set of the other tubes that were present in the radio when I got it?  I feel like three of these (6K7, 6A8, 6F5) may be original as they are all RCA Radiotron branded and the 6K7 is even rusted with bubbling paint.  The 5W4 rectifier (National Union) looks to be in good physical shape, but of course they're all metal so the only things visibly glowing in the radio are the dial lamps.

   

As for the power switch, is it likely to be the case that it is salvageable or should I be looking for a replacement?  I'd kinda like to be able to turn it off.

Best wishes,
Roy