01-10-2015, 08:58 PM
As long as the 2 uF you used has a high enough working voltage, then it will be OK.
Here's some notes.
If you were to use an electrolytic for the 2 uF section, the positive goes to the junction of the two 70K resistors, (27) and (28 ). Negative to the bottom of resistor (30) and on to B-.
Positive of the 8 uF section goes to the right side of resistor (49) (on the schematic) and on to the screen grid of the 42 output tube. Negative to B- (terminal 8 of the power transformer).
Now here's where it gets tricky. Chassis ground is positive in relation to B- in this set. Therefore, the positive of the 10 uF section (which only needs to be 50 WVDC) goes to chassis ground. Negative of the 10 uF section goes to B-.
One more thing. The voltage readings taken by the Philco factory in 1933 were done with voltmeters having an input impedance of 1000 ohms per volt. These crude old voltmeters loaded down the circuits under test, and all of those readings are actually inaccurate! Using today's modern DMMs, which have an input impedance of several megohms per volt, do not load down the circuit under test nearly as much, and provide much more accurate readings. All of this means that many (if not most) of the readings you take with your DMM will be higher than the published data.
Here's some notes.
If you were to use an electrolytic for the 2 uF section, the positive goes to the junction of the two 70K resistors, (27) and (28 ). Negative to the bottom of resistor (30) and on to B-.
Positive of the 8 uF section goes to the right side of resistor (49) (on the schematic) and on to the screen grid of the 42 output tube. Negative to B- (terminal 8 of the power transformer).
Now here's where it gets tricky. Chassis ground is positive in relation to B- in this set. Therefore, the positive of the 10 uF section (which only needs to be 50 WVDC) goes to chassis ground. Negative of the 10 uF section goes to B-.
One more thing. The voltage readings taken by the Philco factory in 1933 were done with voltmeters having an input impedance of 1000 ohms per volt. These crude old voltmeters loaded down the circuits under test, and all of those readings are actually inaccurate! Using today's modern DMMs, which have an input impedance of several megohms per volt, do not load down the circuit under test nearly as much, and provide much more accurate readings. All of this means that many (if not most) of the readings you take with your DMM will be higher than the published data.
--
Ron Ramirez
Ferdinand IN
