My Acratone radio

This radio is pretty much a mystery set. I found it cheaply at a local antiques store. It is a bad quality radio, cheaply built, and severely damaged by improper repairs. So far I have not devoted much efforts into it, but I will let you know about it on this page when I do finally restore it.

As far as I know, Acratone was a brand name of Federated Purchasers, and from what I have heard, these radios were sold in department stores and supermarkets more than in specialized stores. That explains why they were made as cheaply as possible.

This radio uses a variation of the famed all-american-five circuit. A 6A7 tube is used as converter, a 6D6 as IF amplifier, followed by a 6SQ7 detector, AGC and audio preamplifier, and a 43 output stage. It has a 6G5 magic eye, and the rectifier is a 25Z6. What a mess! There are octals, old-style bases, top-cap tubes and single ended ones, glass and metal, all mixed. According to this mix of tubes, the radio must have been made around 1936, 1937 or so.

The filaments are series connected and need 300 mA, and they are fed without any transformer, using a huge octal-base dropping resistor. As this radio is powered from 220V, and the filament string needs just about 70V, the other 150V are dropped in the resistor, making for a hefty 45W of power dissipation in that resistor alone! The result: The radio's top is badly scorched. Total power drain is about 100W, quite a lot for a simple small radio like this!

But there are good things too: The radio has a beautiful golden airplane dial. The three bands are marked "Broadcast", "Foreign shortwave", and "Amateur and police". This latter band covers right up to 50MHz!

I repaired the radio to a functional state. This involved, among other things, finding out that the 6A7 tube had a bad connection at the base! I unsoldered the base pins, removed the base from the bulb, cleaned everything, glued the base back on and resoldered the connection wires to the pins. The tube is now as good as new!

I had no choice but drawing the schematic myself. I needed it in order to understand what else was wrong. The set had several misplaced connections, obviously from previous repair attempts by people who failed to discover the bad tube!

The dropping resistor was open too. I patched it, but some more definitive repair, or replacement, is needed. 

Here is the underside of the chassis. It's easy to see the cheap build of this radio. Even after all my efforts, it's not possible to really use the highest frequency band. The oscillator just stops above 30MHz or so. I wonder how it is supposed to work up to 50! The 6A7 tube was not known to be a VHF device...  Maybe replacing some leaky capacitor gets it running even up there, but I would not bet on it.

What discourages me from restoring this radio is the fact that the cabinet is covered in what used to be called "paper veneer". In fact it's not even paper, it looks more like if a pattern mimicking expensive wood was printed onto the cheap base wood and lacquered over. Wherever it is scratched (and it is in many places!), the cheap yellow-white base wood shows through. And on the top, there is the large, black scar left by the heat from the resistor! I cannot repair that. I could only glue some real veneer, or some wood-grained paper over it all, but this would be grossly non-original. Any ideas, anyone of you?

The plastic dial window is cracked. It has a quite special shape, and I have no idea how to fix or replace it.
All four knobs are different, and obviously non-original. Anyone has an idea how the original knobs looked?

I was tempted to buy this radio only because Acratone radios are uncommon here. But now I don't know how to get it in shape!

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