38-09 Electrolytic question - Printable Version

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38-09 Electrolytic question - Hamilton - 03-07-2023

https://philcoradio.com/library/download/service%20info/wiring%20diagrams/vol2/split/Part37-Philco%20Wiring%20Diagrams%20Vol.%202.pdf

I’m working on a Philco 38-09 and I have a question regarding one of the electrolytic caps, part #45. The enclosed photo showing the blue circle is the 25 mfd cap with two wires attached to it. The two-tone yellow/green wire goes to the field coil and the red goes to Pin 6 of the 5Y4 tube where it is connected with a black wire that goes to the power transformer. I’m assuming that is my + connection for my replacement cap and the red circle is my - connection.

I’m still new to this hobby and I hoped someone could confirm whether I’m correct and enlighten me as to the purpose of why this cap is connected to the 5Y4 tube and not directly into the power transformer.     

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RE: 38-09 Electrolytic question - morzh - 03-07-2023

The one going to the rectifier tube's filament, field coil and transformer - PLUS
The other one is minus.

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RE: 38-09 Electrolytic question - Radioroslyn - 03-07-2023

Red circle is the - side and blue the +. You may want change the 38-09 to 38-9 it's less confusing.

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RE: 38-09 Electrolytic question - morzh - 03-07-2023

I can see a Candohm...

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RE: 38-09 Electrolytic question - Hamilton - 03-07-2023

Thanks Morzh and Terry.

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RE: 38-09 Electrolytic question - RodB - 03-07-2023

Hi Hamilton, the answer to your question regarding 5Y4 pin 6 is pin 6 is an unused pin so is being used as a termination point. You will see this often especially for B+ or B-.

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RE: 38-09 Electrolytic question - Hamilton - 03-07-2023

Perfect thanks Rod. Appreciate the explanation.

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