[Nick3092]

Not even sure you need it. I just put the dial in the way it came from Daze, the paper ring was in pieces.

Yeah, I'm not sure what purpose it serves.  As long as mine is in fairly good shape, I figure I'll keep it in place.  I took a closer look at the material.  It kind of reminds me of speaker material.  So I took some Sobo fabric glue that I use to repair tears in cones, and used it to put this ring back together.

I built a stand (my existing stand wouldn't accommodate this chassis) so I can power the chassis up and run some checks.  The plate on the RF tube had no voltage.  I pulled the RF chassis again (which is still a pain, but it gets easier once you've pulled it once and you know what you are doing) and checked it out.  Turns out when I disassembled the RF chassis, I disconnected that wire and didn't reconnect it to pin 3 on the socket.  That wire carries B+ to the tube.

However, the radio behavior hasn't changed.  I still have a low constant tone when I inject at the antenna terminal for about 3/4 of the volume.  Then it gets louder on the last 1/4 turn of the volume knob.  I noticed that the sound coming out of the speaker when injecting RF into the antenna (and I have the volume up in that last 1/4 turn where it starts getting louder) the tone is warbling/distorted. Which I think is a sign of oscillation, right?

I just got a signal tracer, so I figured out now might be a good time to try it out.  I used the signal tracer, and the tone sounds clear at the antenna terminal, the RF grid cap, the mixer grid cap, and the 1st IF grid cap.  It sounds a little distorted then at the 2nd IF grid cap.  So I went back to the 1st IF plate and it sounds a little distorted there too.  So
I'm guessing the distortion is being introduced around the 1st IF.  But that is as far as I know how to check.   I briefly looked at all the connections to the 1st IF, and everything seems good.  The plate voltage is a little low (188-195, usually a little lower on 2nd than 1st) as it should be around 220.  I know DMM's measure differently due to the input resistance.  So I'm not sure if this is actually relevant.

I also worked backward form the speaker to try and figure out my volume issue by injecting an audio signal at various points:

Radio off, pin 3/plate of both output tubes - I can hear a faint tone in the speaker. For the rest, the radio is on.
Driver pins 3 & 4 (tied together) plate & screen - I get a slightly louder tone than I did with the above test.
Driver pin 5/grid - I get a much louder tone.
1st Audio pin 3/plate - I get about the same tone as the driver grid gave me.
1st audio pin 5/grid - I get a tone that is controlled with the volume knob on the radio. But it seems to be acting funny:

From low to about 1/4 turn, the tone gets louder.
From 1/4 to 1/2, it starts getting quieter.
From 1/2 to 3/4 , it gets louder again.

I'm wondering if something is coming through the volume pot that is stomping on my signal somehow.  To rule out the volume pot being an issue, I did some checks on that.

If I move my audio signal to the "top" of the wiper, I see the same behavior as with the radio - low constant tone for about 3/4 of the volume.  Then it gets louder on the last 1/4 turn of the volume knob.

I ohmed out the the outer terminals on the pot, I get a little over 1.7M.  Then I tested wiper to ground/chassis on the volume control. All the way low I see 22 ohms. as I turn it to the maximum, the resistance steadily climbs. At 1/2 way its about 640k. Although, something odd does happen around 3/4 of the way. The resistance pauses briefly at about 700k or so. It just briefly keeps reading that as you turn it, then it starts increasing again to 1.7M at the max.

After staring at it for a while, I think i figured out that brief pause in resistance changing.  This is a 4 terminal pot. There is a tap on the back that goes to R103 and the tone caps. If I measure that tap to ground, I get 700k. So that pause must be where the wiper is going over the tap. So I'm pretty confident that the pot is good and doing what it should.  But something else seems to be suppressing the signal.

If anyone has any ideas on troubleshooting the distortion and/or the volume issue, I'm all ears.