James's Aetna 502 Repair/Restoration Project

Note: this radio is no longer in my collection. This page will be removed in late 2024.

My Charlie-Brown-Christmas-Tree radio. Found it sitting forlorn in the back of a Deseret thrift shop. Normally the oldest thing you see in these places is from the mid-1960s, unless it's a Kodak camera.

But as I got a look at it I could see why nobody had already bought it. The glue in the joints of the cabinet was almost gone and it was coming apart no matter how gingerly you handled it. The glass shell on the 76 tube was rotating freely on the base. Something had punched through the grill cloth and the speaker cone. The cabinet laminate was missing or peeling away. It's hard to see from this flat angle, but even the cabinet wood base is buckling in the front.

On the plus side, the dial, the bezel and escucheon all looked good. It had three of four knobs. The chassis hardware (the tuner, IF can, etc.) looked decent. It didn't look like it was burned or submerged in a flood. For the $10 asking price, I figured I could take a chance.

Tube Compliment

6A7 - Converter
6D6 - IF
76 - 2nd Detector
42 - Audio out
80 - Rectifier

Aetna was the house brand for Walgreen, the drug-store chain. Like all retailers, they bought their radios from another manufacturer. I haven't been able to determine who made this one. Possible suspects (according to posts on Antique Radio Forum) include Belmont, Detrola, and Warwick.

I picked it up while visiting the Old Man so we both looked it over. The tear in the speaker cone was clean so we were able to glue it back down and it seems to hold pretty well. The voice coil is iffy. He gave me his tube tester so we couldn't test them there, but we pulled the chassis and looked underneath. The line cord had been cut (probably just as well). Someone had already replaced one of the 8uF filter caps, but two were floating free. Most of the rest of the components look original. The wiring is brittle and disintegrating. There's a fair layer of crud all over it.

It survived the ride back home, through the cabinet continues to lose another piece very time I touch it. The Old Man had drizzled a little super glue on the envelope of the broken 76 tube on the off-chance that it was just loose, but it failed the shorts test on my Hickok, and the 6A7 converter tested weak. The others tested okay. All except the 80 were Aristocrat brand, which I'd not seen before. The 80 was a Tung-sol and tested strong; I assume it probably replaced the original Aristocrat 80.

My shopping list so far:

A two-section filter can. The original filter is two 8uF at 450V. JustRadios.com has a two-section 10uF @500V can that will do the trick. Arrived and ready to go in.
I had a better 6A7, so I need one for the shelf. I don't have a 76 (I probably do but I'd have to rob my Packard-Bell to get it). Received from the National Radio & TV Museum.
I need a knob. Considering all the other things to be done, I'm leaving this until much later.
Grill cloth (looking).
A plastic tuning dial disc (described below). No earthly idea.
A new cabinet (good luck with that.)

Making a Hash Out of Everything. This thing's been sitting on my bench now for nearly a year. The chassis is out, figuring I'd at least get it to play, and figure out the cabinet later. I'd start with the big filter cap. Cut them out, wired in replacements, did it wrong, and noticed when the transformer started to smoke. I yanked it out, and realized I'd gotten it all wrong.

Every so often I'd get up the nerve to look at it again, but didn't do it for whatever reason, some good, some bad. I refused to move it off the bench because I didn't want it to be come yet another project that's started but never finished. Finally, in November (I bought this last Xmas), I traced the wires and identified how the capacitors should go. I identified the wires (harder than it seemed it should be). Ready to go.

I took a tip from Mr. Carlson's Lab, and soldered the new two-section 10uF can onto a terminal lug strip. I then proceeded to connect the wires wrong again, but this time differently, so that I blew up one of the caps (not according to Carlson's lab). Of course, these were the last two 10 uF high-E capacitors in stock. I ordered more to destroy and they're on the way.

Meanwhile, there's a thin plastic disc behind the dial face that's as brittle as a centenarian's hip. Every time I look at it another piece breaks off. That's another thing I'm going to have to replace, but I don't yet know with what. The plastic disc is bolted onto the tuning condenser, and it's edge-driven by the shaft of the tuning knob. That's going to be tough to replace.