[Findm-Keepm]

Motorola might have - I've got a non-working, AM only label-less Motorola table model that is AC powered. The transistors (TO-5 case except for one in the RF section, a TO-1) all have 185 and 43X (x being either 1, 3, or 5) date codes. The speaker code is 6438, making it a 1964 produced radio, perhaps. (Christmas model??) Motorola's address on the radio is Franklin Park, IL.

The output transistor is an aluminum Motorola TO-3 device, but I can't decipher the part number, R1B or RIB. No relevant ECG/NTE/SK cross. Raw AC gets rectified by a top hat rectifier, sent through a sand-ohm resistor (5 watter), capacitor (known good!) and then straight to the emitter of the output (PNP!) through the output transformer (good) and then to the amp/radio stages through either a 6.8K or 68K resistor (it's been hot, and the multiplier color code looks orangish red, but read over 100K out of circuit)

It's the size of a tube-clock radio, 13" long but very vanilla, with a 4" square speaker (plastic speaker grille) and two knobs - tune (direct drive, with aplastic tip on the shaft for AC isolation) and on-off/volume, pressboard back with evidence of two missing labels. Power consumption is a whopping 13 watts, IF it worked. My problem is that the B+ resistor gets extremely hot, but little B+. It has been worked on before, and with no schematic, component values are tough to figure. My guess is the something is biasing the output on all the time. All of the transistors check good in circuit - I need them to check them, as the amp stages are all directly coupled, and I could be reading other junctions in-circuit.

The radio is in my "wish pile" - the above is from some notes I had on it for my schematic search. An eBay saved search for "Motorola AM radio" has turned up nothing yet.

Hope this helps. Cheers,