I am refurbishing a beautiful Philco 40-190 for a friend of mine. I've replaced all the resistors and caps after checking the service bulletins. However there is one resistor that I cannot find: The 10K resistor (1B) that is supposed to be in parallel with a 250 pf cap (1A). There is no sign of it every being there; the solder joints are obviously old. Could this be the result of another service bulletin?
(1A) and (1B) are inside the loop antenna. There is usually no need to worry about these components as they are not exposed to any significant voltage.
(05-31-2016, 09:11 PM)Ron Ramirez Wrote: (1A) and (1B) are inside the loop antenna. There is usually no need to worry about these components as they are not exposed to any significant voltage.
Thanks for the info. Probably never would have looked there.....Tom
It's best to not unwrap the loop antenna covering as it has wires embedded in it which serves as an electrostatic shield to reduce noise. Cut the covering open, and you destroy the shield. The loop will still work okay, but I would rather leave it alone.
(06-01-2016, 02:07 PM)Ron Ramirez Wrote: It's best to not unwrap the loop antenna covering as it has wires embedded in it which serves as an electrostatic shield to reduce noise. Cut the covering open, and you destroy the shield. The loop will still work okay, but I would rather leave it alone.