Radiola 25


I was trying to figue out on what to tackle next. I have a Radiola 25 sitting here that the seller said had a bad "catacomb" I assumed the "catacomb" was a sealed tar coil box. As this is a fairly early radio, I haven't found any schematics in Riders. The info I have seen so far, requested that the servicing radio tech sent the failing "catacomb" back to RCA for repair. Does anybody have the particulars (schematics) of this catacomb?

I can mail you a redrawn schematic for the box with all the parts values; it was published in the MAARC bulletin a few years ago.

Originally the box was divided into shielded partitions so they called it a catacomb (Roman tombs). It's potted in wax and is not hard to disassemble if you take your time. Put it in a slow oven for a few hours and lift the works out of the melted wax. Pour off the wax and save it for restuffing caps or something; you don't need it again. You'll probably find that the shrinking wax has broken some of the coil leads, and repair is obvious. Audio transformers go bad, and I once had a mica cap that leaked and was noisy.

Just don't try to hurry the melting process: wait for all the wax to melt out of the RF coils.

I e-mailed some info on your 25 also.

D Augustine KC8RKC