Hi guy's, Restoring a Philco 51-931 code 122, the Rider schematic shows a 35Z5GT as the rectifier but this radio has a 35Y4 loctal tube. It should not be an issue for restoration, just thought it was a little odd.
Guy's, after posting this thread I noticed that this radio also has a 50L6 instead of the 35L6 which the schematic shows. It looks as thought this is an original tube.
Got this radio up and working, put the 35L6 in the radio instead of the 50L6, someone must have replaced this tube. The radio has very good reception.........
Does your radio have a 100 ohm resistor (R5) in series with the tube filaments? It looks like it connects between the filament pins of the two 7B7 tubes.
This resistor drops the filament voltage by 15 volts, which is the same amount that would be needed for a 50L6 compared to a 35L6. If there is no R5 series resistor, the circuit requires a 50L6.
(02-14-2017, 10:38 AM)Mondial Wrote: Does your radio have a 100 ohm resistor (R5) in series with the tube filaments? It looks like it connects between the filament pins of the two 7B7 tubes.
This resistor drops the filament voltage by 15 volts, which is the same amount that would be needed for a 50L6 compared to a 35L6. If there is no R5 series resistor, the circuit requires a 50L6.
Thanks for your reply, yes is does have a 100 ohm resistor there in fact it was a dog bone type which I replaced..................
Thanks again.