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Full Version: Newbie with Electrolytic Problem
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I am a newbie working on a Westinghouse 430A. I want to replace this radios electrolytics before I do anything else. This radio originally was built with a 10 mfd and a 16 mfd electrolytic. 

The original 10 mfd was replaced at some time with a Sprague capacitor containing 2 - 10 mfd's and the 16 mfd cap is original. The Sprague has one yellow wire connected to the base of the existing 16 mfd cap the other yellow wire going to a terminal strip. This cap is grounded to the chassis.

The original 16 mfd cap has that yellow wire from the Sprague attached to it's base as well as two red wires. One red goes to the rectifier tube, and other red wire going to the same terminal strip as the Sprague, but a different lug.

I'm enclosing a photo of the Sprague cap and the original 16 mfd aluminum cap. Also a shot of where they are connected to the terminal strip. 

Unfortunately at this time my ability to follow schematics is poor and I'm not sure whether the previous work on this radio's electrolytics was done properly. 

I need some guidance as the where the + and - connections of my new caps need to go to ensure proper polarity. 

Any assistance would be greatly appreciated.
The schematic for the 430A.
As per the diagram the two - leads connect to the chassis and the +'s connect to either side of the field coil. Do disconnect the old caps as they will cause problems if left in circuit.
Hi Radioroslyn

The Sprague capacitors  + is currently attached to the same lug as the field coil on terminal strip so do I have to move it over to a different lug or can all the +’s be connected together on the same lug of that terminal strip. I ask only because you mentioned that they should be on either side of the field coil.

I will be disconnecting the old 16 mfd aluminum cap but what do I do with the one red wire that’s currently going to the rectifier tube. 

Sorry if this is basic I just don’t want to mess it up.
Hi Radioroslyn

Got it working fine thanks! I just joined the two reds from the old 16 cap, the new cap and soldered them together. It’s got a common ground with the 10 mfd. Tested in on my dim bulb and all good. I was worried somewhat because I messed up the polarity on a different radio and messed up the power transformer.
The old caps need to be OUT OF THE CIRCUIT! Do not leave them connected as they will short and damage the 6X5 and the power transformer.
Terry is correct, please take those old capacitors out of circuit.