The backstory on this little clock radio is that it was one that I kept next to by bedside when I was a teenager. I don't think I ever opened it up, I just ran it the way it was with the little bit of hum that it produced. The alarm clock feature provided a soft wake-up as the tubes came alive in the morning when the alarm cam closed its contacts at the appointed hour. The sleep feature provided a way to fall to sleep with music or news and have the radio turn off on its own. It is a pretty clever little device. It came out of the bottom of a box in the basement looking like this. There is a white substance on the knobs, which appeared to be mold?!?! (I have noticed this on the old Magnavox TV that is still in that basement.)
The case opens easily by popping the cardboard back off. That will need some tender loving restoration as it has begun to split. The tag is still legible, but doesn't really contain a year of manufacture. The quality control stamps are still visible. I only gently cleaned the chassis because it has a nice protective layer of waxy cosmoline on it. This protective layer has preserved the chassis and all the components from any oxidation. I've seen this on a few circuit boards in the past, but not as generous an application on a tabletop radio like this.
The knobs pop off and the four screws in the bottom allow the chassis to slide out. The only trick was gently prying off the clear front pieces so that the tuning pointer could be removed. The once bright and shiny gold bezels are faded. I think that some gold leaf paper from the craft store would look grand when properly cut and pasted in. There's no preserving what is there. It looks awful.
The plastic case itself is unbroken, but scratched and marked. Some gentle rubbing with a Mr. Clean magic eraser pad cleared off the marks. Some additional polishing to buff out the case may be needed as final preparation for re-assembly. Overall it looks good for its age, and only one knob is missing.
The cosmoline impregnated a lot of dust on the top of the board over the years and I decided to leave it alone. It ran when parked, remember. All it should need is a few capacitors and maybe an alignment tweak. The capacitors were all common values and quickly replaced. The circuit board itself is strong, but the traces are pretty fragile. Much care was given to keep from destroying the integrity. The main filter cap was easily pulled out with only minor damage to the surrounding traces. A dremel tool easily sliced through the electrolytic body after removing the cardboard cover. Once free the base of the original capacitor is re-usable as a carrier for the new filter capacitors. They are too big to fit in cross-ways, but fit nicely stacked one on top of the other with some lead extensions. The mounting leads had to be drilled through to make contact with the actual contacts since the interior of the rivets and feed wires out of the original capacitor guts are aluminum. The cardboard cover was re-used to hide the capacitor modification.
What is this big mystery component in the middle of the board? It is large and square. Is it a resistor / capacitor network? I didn't pay much attention as long as the radio decides to play.
Which it did after all the paper capacitors and burst bumble-bee cap was replaced. And it plays beautifully with no hum and good station selectivity. To make it safe a new cord is in order.
Directing our attention back to the case, the bezels needed attention to make this piece of atomic age art presentable. I visited the local craft store and found some nice bronze-colored plastic film. It is quite thick and actually challenging to cut with a razor blade. I think it will work just fine hidden behind the plastic bezels.
For a final product, I would say that it turned out really well. It looks the part, it plays, and it keeps time. What more could I want !
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