08-21-2015, 02:54 PM
I've started work on restoring a 37-611.
I need to locate a schematic for the version I have.
It's setup differently than the common schematics I have found.
It uses the same tubes but the chassis layout is a bit different.
There are 3 bakelite caps instead of 2. Plus the electrolytic caps are marked differently along with a change in the power supply.
There are 2 "flexible" resistors, one is definitely open, according to the schematic I have, I think it's suppose to be 400ohms and feeds the cathode of the output.
This would be a lot easier if I could find the variation of the schematic that applies to this chassis.
Otherwise, it will require a lot of tracing wires. And ignoring component markings.
i also will have to trace the connections on the bakelite to figure out what the caps are suppose to be inside it, assuming it wasn't a change added.
The other flexible or possibly fuse able resistor between the 2 main filters measures 38 ohms, and the only other resistor of it's type listed on the schematic I have is 20 ohms. ( has it changed value or was it changed by the factory?)
Another thing. One of the electrolytic can terminals is marked with paint -RED paint , Yellow paint , and none.
According the the values on the cap- RED is Common? Yellow, and No paint are the cap sections?
This is normal for philco radios of the time?
Anyone out there have variations on the schematic for this model? 37-611
What should be used to at least replace that one flexible resistor (wattage) I know is bad.
I removed the covering on the flexible resistor to verify what it was and that it is open.
See attached picture and drawing on schematic showing that area
I need to locate a schematic for the version I have.
It's setup differently than the common schematics I have found.
It uses the same tubes but the chassis layout is a bit different.
There are 3 bakelite caps instead of 2. Plus the electrolytic caps are marked differently along with a change in the power supply.
There are 2 "flexible" resistors, one is definitely open, according to the schematic I have, I think it's suppose to be 400ohms and feeds the cathode of the output.
This would be a lot easier if I could find the variation of the schematic that applies to this chassis.
Otherwise, it will require a lot of tracing wires. And ignoring component markings.
i also will have to trace the connections on the bakelite to figure out what the caps are suppose to be inside it, assuming it wasn't a change added.
The other flexible or possibly fuse able resistor between the 2 main filters measures 38 ohms, and the only other resistor of it's type listed on the schematic I have is 20 ohms. ( has it changed value or was it changed by the factory?)
Another thing. One of the electrolytic can terminals is marked with paint -RED paint , Yellow paint , and none.
According the the values on the cap- RED is Common? Yellow, and No paint are the cap sections?
This is normal for philco radios of the time?
Anyone out there have variations on the schematic for this model? 37-611
What should be used to at least replace that one flexible resistor (wattage) I know is bad.
I removed the covering on the flexible resistor to verify what it was and that it is open.
See attached picture and drawing on schematic showing that area
