[lasurveyor]

Thank you so much for your post. You've given me some new things  to look at and a new way of looking at others. Just what I need. Like I said, this isn't uncommon to have a problem at power up but it gets found and that's fun. But this one's driving me nuts. You're right that I need a better schematic. I'm going to go through your post carefully, give me a few days and I'll get back.
Thank you!
Alan

[jcassity]

one thing to keep in mind,, and this may not make any sense.............

on that shielded pair of wires you have,,,
on my set i had no continuity at all, yet when i bypassed one of them with a wire, the set came back to life.

so...... the idea was that the insulation on the wire that is passing through that shield, there must be a crack somewhere and its arc flashing to the shield and grounding out when the set is powered on. over a short period of time the reception would go away.. in your case though, reception is not present but there is noise so..............

[jcassity]

on another set i just finished up, when i put the chassis back into its bakalite cabinet and screw it down on the bottom, the set crackles and pops. i found out yesterday that the bakealite chassis is slightly warped and by adding the bottom mounting screws this "twists the chassis" and apparently has an affect on some connection somewhere. ,,, like a cold solder joint or whatever. my fix is to just snug down only the mounting screws.

good luck

[lasurveyor]

    I took another look at the IF transformers. The first one has continuity and 15 ohms on both sides, the second one has continuity and 15 ohms on one side, open on the secondary. So I had a Pac Bell parts radio with an IF transformer, 20 ohms on both sides. I jumpered this in after removing the original and for the first time I received a broadcast signal, the strongest station locally. Very, very distorted, not so much that I can't make out the words, and there is a background buzz, maybe the same one I've had all along. Getting the broadcast signal has me excited though.

Before I solder it in, this transformer should be just fine, right? The 48D is IF 460, the loaner model 651 is IF 455. Could be interesting to see what I get if I bypass the open transformer.

Alan

[David]

After you get the replacement installed you have a great project to start 2019 rewinding the old IF can.

[lasurveyor]

Maybe I'll get started on Christmas Day, really annoy the wife.
Alan

[OldRestorer]

Maybe I'll get started on Christmas Day, really annoy the wife.
Alan

[jcassity]

my math says a 60ohm resistor across the pri and sec on that replacement IF will get you in the 15ohm area which for some reason i feel compelled to think it would be better for the radio's original design.
the next thing is to find out if the cap on each side is going to give you problems.
meaning,,, is this a tuned slug or tuned cap??????

i would get the old IF under a magnefying glass and find out if you can "see" the open and repair.,, tiny wire there like what,, 60awg?????