Mike,
I sketched what to do to make your Radiola 60 power supply exactly the same as the Theremin power supply. I pulled the power supply out of my Radiola 60 to see exactly what you were dealing with. Refer to the sketch I made at http://members.tde.com/mmckeown/Theremin/rad 60.jpg and figure 7 in the RCA manual. In effect, all that is being done is make the power supply as shown in figure 7. In answer to your questions:
I would cut the pilot light wires at the resistor connections. I would keep the power switch and add enough wire to reach the new switch location.
The Radiola 60 gets the audio from the plate circuit in a different way than the Theremin. Make the changes shown in my sketch and figure 7 and you will be ok. Remember you now have high voltage on one of the output terminals. The Theremin runs the high voltage to terminal 2 through the speaker and the Rad 60 doesn't.
The center tapped resistors were a common way to reduce AC hum in the old days. Remove the black wire between the center taps and the green-red wire going to the output jack. Add a wire from the left, unconnected center tap to terminal 6. This in reality just grounds it. The green-red wire to terminal 5 from the other tap goes to the main Theremin chassis where it is grounded through a 550 ohm resistor bypassed with a 2 mfd capacitor.
Remove the wire going from the other output jack to the lower right terminal (#8) of the choke/capacitor assembly. Add jumpers between #2, 7, and 8 terminals of the assembly. Cut the red wire going from terminal strip number 2 to terminal 1 of the assembly so that you can connect each side of the cut wire to each output jack. Add the capacitor across the output terminals.
Colors are always a problem with these old cloth covered wires. Be very careful not to bend sharply or damage the cloth insulation. I use an ohm meter to be sure of what wire goes where.
The "plastic" ring in the bottom hole of the Rad 60 cabinet is similar to the one in the bottom of the Theremin so you can use that. Also the audio transformer marked GW-42 is the same as the interstage audio transformers in the Theremin.
Sorry about the oversimplification of the power supply comparisons but the changes are minimal and if you make the Rad 60 power suppy look the same as figure 7 you should be ok. When you power the supply up do it without the tube at first and if no smoke, put in the tube and check for smoke again.
It may take me a few days to get to the coils.
Mark
I sketched what to do to make your Radiola 60 power supply exactly the same as the Theremin power supply. I pulled the power supply out of my Radiola 60 to see exactly what you were dealing with. Refer to the sketch I made at http://members.tde.com/mmckeown/Theremin/rad 60.jpg and figure 7 in the RCA manual. In effect, all that is being done is make the power supply as shown in figure 7. In answer to your questions:
I would cut the pilot light wires at the resistor connections. I would keep the power switch and add enough wire to reach the new switch location.
The Radiola 60 gets the audio from the plate circuit in a different way than the Theremin. Make the changes shown in my sketch and figure 7 and you will be ok. Remember you now have high voltage on one of the output terminals. The Theremin runs the high voltage to terminal 2 through the speaker and the Rad 60 doesn't.
The center tapped resistors were a common way to reduce AC hum in the old days. Remove the black wire between the center taps and the green-red wire going to the output jack. Add a wire from the left, unconnected center tap to terminal 6. This in reality just grounds it. The green-red wire to terminal 5 from the other tap goes to the main Theremin chassis where it is grounded through a 550 ohm resistor bypassed with a 2 mfd capacitor.
Remove the wire going from the other output jack to the lower right terminal (#8) of the choke/capacitor assembly. Add jumpers between #2, 7, and 8 terminals of the assembly. Cut the red wire going from terminal strip number 2 to terminal 1 of the assembly so that you can connect each side of the cut wire to each output jack. Add the capacitor across the output terminals.
Colors are always a problem with these old cloth covered wires. Be very careful not to bend sharply or damage the cloth insulation. I use an ohm meter to be sure of what wire goes where.
The "plastic" ring in the bottom hole of the Rad 60 cabinet is similar to the one in the bottom of the Theremin so you can use that. Also the audio transformer marked GW-42 is the same as the interstage audio transformers in the Theremin.
Sorry about the oversimplification of the power supply comparisons but the changes are minimal and if you make the Rad 60 power suppy look the same as figure 7 you should be ok. When you power the supply up do it without the tube at first and if no smoke, put in the tube and check for smoke again.
It may take me a few days to get to the coils.
Mark
