Help to identify condenser in Philco 39-116 -
edison - 04-29-2020
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
RE: Help to identify condenser in Philco 39-116 -
Link - 04-29-2020
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
RE: Help to identify condenser in Philco 39-116 -
morzh - 04-29-2020
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.
RE: Help to identify condenser in Philco 39-116 -
gregb - 04-29-2020
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
RE: Help to identify condenser in Philco 39-116 -
edison - 04-29-2020
Tanks Link and morzh and Gregb.
This picture is more enlightening.
Cheers, Carlos
RE: Help to identify condenser in Philco 39-116 -
Link - 04-29-2020
Ahhh, now I see two leads!! : )
RE: Help to identify condenser in Philco 39-116 -
morzh - 04-29-2020
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.
RE: Help to identify condenser in Philco 39-116 -
edison - 04-29-2020
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
RE: Help to identify condenser in Philco 39-116 -
morzh - 04-29-2020
I tried film caps....too large.
Mouser has bipolar/nonpolar aluminum caps.
https://www.mouser.com/ProductDetail/Nichicon/UES1H330MPM1TD?qs=sGAEpiMZZMtZ1n0r9vR22bYzEsjb8gAOwp6MQPnjphw%3D
Here's one.
RE: Help to identify condenser in Philco 39-116 -
edison - 04-29-2020
Thank you.
I will do with two electrolytic capacitors in series.
Cheers.
Carlos
RE: Help to identify condenser in Philco 39-116 -
morzh - 04-29-2020
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).
RE: Help to identify condenser in Philco 39-116 -
edison - 04-29-2020
Thank you, for the explanation.
Best regards,
Carlos
RE: Help to identify condenser in Philco 39-116 -
Nathan Slingerland - 04-29-2020
The 1942 parts catalog lists the 30-2361:
http://philcoradio.com/library/download/parts/catalogs/1942/Philco%20Parts%20Catalog%201942.pdf
Sadly no info other than it is a motor start cap as others have surmised.
RE: Help to identify condenser in Philco 39-116 -
rfeenstra - 04-29-2020
there you go, Nathan! Is it a split phase motor that requires a run capacitor?