Radiola 60 Power Supply Rebuild

[Rob Uthe]

I picked up this radio (the Brunswick version of the Radiola 60 superhet) about 8 months ago. It was in terrible shape when I got it; the cabinet was smashed and the power transformer was burnt out. I restored the cabinet several months ago and jerry-rigged a power supply using three replacement transformers. I’ve rewired and tested the radio itself, and it works fine using the replacements. However, I wanted to make the radio safe and usable in the house, so I recently decided to re-pot the new inductors into the old cans.

This is a very difficult job; the old cans are filled with tar. The old paper-wax capacitors in the filter block were bad (possibly the cause of the bad transformer), so that had to be emptied as well. The radio has 7-type 27 tubes, which draw 12.25 amps of current for the heaters at 2.5 V. I couldn’t find any 2.5 V transformers that could handle that current draw, so I paralleled two 2.5 V 10 Amp Hammond transformers. This took up additional space, so I decided to put them in the can that originally held the old capacitors. I decided to replace the output choke at the same time.

I removed the old transformers by putting them in the freezer overnight. The tar shattered like glass, and the old components could be pulled out.

I am most of the way through this; I will update when all of the caps are installed and the power supply is working again. I also still intend on cleaning and repainting again before it is “finished”.

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[Rob Uthe]

Here are photos of the new power transformer (Hammond with 5V and 6.3 V windings, the latter dropped to 5V with resistors for the 171A tube), the choke & heater transformers to be stuffed in the capacitor filter can, a rough paint job before final cleaning and rewiring.

• This reply was modified 2 years, 7 months ago by Rob Uthe.

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[Rob Uthe]

Putting it all back together; both chassis completely rewired. Voltages are good, and the radio plays better than ever. I did add a three-wire cord with AC line filter.

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[Rob Uthe]

Finishing up; power supply wired into radio chassis. Most of the wiring has been replaced in the radio with new cloth-covered wired (not original colors) after a previous owner tried to hookup a power cord to the antenna & ground wires and destroyed the antenna grid resistor. This caused some of the wire to be charred and brittle.

The radio is shown with Arcturus Blue type 27s

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[Rob Uthe]

Mostly reassembled; I only need to add the back as the plate over the tuning dial.

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[Rob Uthe]

A few “before” photos

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[paolo1960]

Good morning Rob, I need your help.
I saw this interesting post of yours, and since I too would like to restore the power supply of a Radiola 60, found at the home of an elderly aunt, I have some questions to ask you.
First of all I would like to know if it is possible to choose transformers with the primary at 220Vac, in order to make it usable with the current mains voltage. Second question I would like to know the type of power transformer you used. Sorry but I’m not much of a radio expert and my electronics degree dates back more than 35 years, so I’m very knowledgeable on the subject. Thank you in advance for any information. Best regards. Paul

[Author]

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