05-26-2007, 12:52 PM
Thanks Ron for the information. While the service bulletin is indeed different from Riders, it does not match my set. For example, R28 lugs 3 and 4 in Riders shows 1500 ohms for the 46E and a small value for the 46. That matches my set. But you can see from the schematic in the bulletin that the 46 and 46E could not be the same if R28 were indeed 1500 ohms since it is shown to be in series with the filaments! In actual fact, that section of R28 is in parallel with the 3 type 14 tube filaments in my set, which works out. In my set, the B+ for the 1st audio type 17 tube is tapped off of the filament string rather than supplied from the high B+ line.
The underside of my chassis is stamped EXPORT in ink, big letters.
The resistor values for the 46E in Riders are incorrect - the values in the bulletin are closer to my set. The 46E could not work using the values in Riders! But the schematic in the bulletin could not be correct either since for example the plate and screen voltages on the tubes other than the outputs would be too high. In my set, R37 is 32K rather than 13K.
But the difference between the 46 and 46E is more than just resistor values and the ballast: the filament string wiring on the model 46E is very different from the 46, and makes sense voltage and current wise (assuming the voltages listed in Riders are correct, which they may NOT be).
There was a guy that was selling a 46 chassis on eBay, and he stated that that set was designed to get power from the railroad DC in Manhatten for example. I sure would like to know more about how that was done!
Thanks again,
The underside of my chassis is stamped EXPORT in ink, big letters.
The resistor values for the 46E in Riders are incorrect - the values in the bulletin are closer to my set. The 46E could not work using the values in Riders! But the schematic in the bulletin could not be correct either since for example the plate and screen voltages on the tubes other than the outputs would be too high. In my set, R37 is 32K rather than 13K.
But the difference between the 46 and 46E is more than just resistor values and the ballast: the filament string wiring on the model 46E is very different from the 46, and makes sense voltage and current wise (assuming the voltages listed in Riders are correct, which they may NOT be).
There was a guy that was selling a 46 chassis on eBay, and he stated that that set was designed to get power from the railroad DC in Manhatten for example. I sure would like to know more about how that was done!
Thanks again,