09-03-2008, 11:14 PM
Neal:
I opened up the heater circuit resistor, thinking that the wires might be crimped, rather than soldered. But the leads had been soldered at the factory before I was born. The ohm meter showed no open circuits. I ruled out that resistor.
If the receiver died on the table after you reolaced the capacitors, you obviously have to retrace your steps and find the tube socket terminal to which you mistakenly connected the new capacitor. (I've made the same mistake on a 42-327 Philco, only I was replacing crumbling insulated wire in the 2nd-IF and detector circuits. I haven't had time to trace the circuits, but I've gone so far as to purchase a secon working 42-327 in order to measure resistance at each socket terminal and make my own resistance chart for the set to find any deviant resistance.) To help troubleshooting here, draw a component layout sketch for your set. Draw a circle to represent each tube base in your radio and write numbers sequentially from 1 to 8 around the circumference of that circle. The numbers will represent the socket pins as seen from under the radio. Consult the tube data base in Nostalgiair and print out a diagram for every tube in the set; note what each terminal number connects to inside the tube, e.g., plate, grid, heater (the heater terminals in this set are all connected to pins 1 and 8.) Then referring to the set's schematic , draw resistor and capacitor symbols and connect by lines to the numbers on each of your tube base sketches. Compare your sketch to the actual hookups in your set. Eventually you'll find your mistaken connection.
Kevin
I opened up the heater circuit resistor, thinking that the wires might be crimped, rather than soldered. But the leads had been soldered at the factory before I was born. The ohm meter showed no open circuits. I ruled out that resistor.
If the receiver died on the table after you reolaced the capacitors, you obviously have to retrace your steps and find the tube socket terminal to which you mistakenly connected the new capacitor. (I've made the same mistake on a 42-327 Philco, only I was replacing crumbling insulated wire in the 2nd-IF and detector circuits. I haven't had time to trace the circuits, but I've gone so far as to purchase a secon working 42-327 in order to measure resistance at each socket terminal and make my own resistance chart for the set to find any deviant resistance.) To help troubleshooting here, draw a component layout sketch for your set. Draw a circle to represent each tube base in your radio and write numbers sequentially from 1 to 8 around the circumference of that circle. The numbers will represent the socket pins as seen from under the radio. Consult the tube data base in Nostalgiair and print out a diagram for every tube in the set; note what each terminal number connects to inside the tube, e.g., plate, grid, heater (the heater terminals in this set are all connected to pins 1 and 8.) Then referring to the set's schematic , draw resistor and capacitor symbols and connect by lines to the numbers on each of your tube base sketches. Compare your sketch to the actual hookups in your set. Eventually you'll find your mistaken connection.
Kevin
