Hi.
I need help to identify one condenser in the Philco 39-116.
The condenser is in the volume control motor circuit and in the schematic, and the parts list, says it’s a electrolytic condenser, but I have doubts, because the capacitor has no polarity and is in an alternating current circuit.
Can you clarify if it is a non-polarized capacitor or not ?
Please see the pictures.
Many thanks in advance.
Carlos
Hi Carlos
I believe it is a 30 uF, 30V electrolytic. It may be constructed to use the case/chassis mount as a neg lead default. How it is constructed can only be installed one way.
I have found Philco has built a lot of circuits that make you go huh, yet they all work. If it is in a motor control circuit, I'd guess it was there to steady out the drive from electrical noise. I am definitely not an expert though.
Cheers, Link
I am not quite sure what an electrolytic polarized cap is doing there.
Is it direction switch?
The current / voltage there is AC and it is bad for a cap.
Back then there were no small size non electrolytic caps of this capacitance so it is probably an electrolytic.
I do not know if by chance it is non-polarized electrolytic.
They did the same in tweeter drive in 38-690, using an electrolytic cap in crossover AC out.
This said, replace it with the same capacitance/voltage film cap.
I would go with a non-polarized electrolytic, I have done a number of RCA motorized sets and that's what they used on the motor. As Morzh stated above standard electrolytic's do not like AC.
Gregb
Tanks Link and morzh and Gregb.
This picture is more enlightening.
Cheers, Carlos
Ahhh, now I see two leads!! : )
It didn't denote + or - anywhere, did it? The sch shows a polarized cap. But if no marking prrsent, it might be a non-pol type, just don't know how available those were at the time.
This is purely academic interest, the cap should be either nonpol electrolytic or film.
Hi.
The two wires are identical and there is no polarity mark.
I assume it is really a non-polarized capacitor.
There is another data that leads me to assume this, which is the inscription of 60 cycles that is written on the capacitor ... I have never seen this on electrolytic (polarized) capacitors.
Cheers.
Carlos
Thank you.
I will do with two electrolytic capacitors in series.
Cheers.
Carlos
Do not do this, it is wrong.
Two back-to-back (not in series, serializing makes for polarized cap) caps do not make a non-pol electrolytic.
It only works for DC where you could bias the centerpoint (if two minusses then to GNd, if plusses then to power).
Thank you, for the explanation.
Best regards,
Carlos
there you go, Nathan! Is it a split phase motor that requires a run capacitor?