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  • #15889
    robert clausen
    Forum Participant

    I am just starting this hobby and was given a Westinghouse 430A. With only 4 tubes and two electrolytic capacitors I thought perhaps I could handle it. Wrong!

    You will have to bear with me since these are probably simple tasks but with no vintage radio meetings due to Covid I am flying blind trying to learn this hobby. I have read quite a bit re: radio restoration but my ability to read a schematic at this time is very poor. I could follow a chassis wiring diagram but I don’t have one for this radio.

    There is a 16 mfd and a 10 mfd electrolytic on my fuzzy schematic but the 10 appeared to be missing when I took the chassis out of the radio. I discovered it’s not missing but replaced underneath with what I believe is a 20 mfd Sprague. My confusion is how to wire in new 10 and 16 mfd electrolytic caps to replace these existing ones. I know the values can be increased on the electrolytics so that not my problem. All my electrolytic caps only have two wires, – and +. The Sprague cap has three.

    The enclosed photos show the existing Sprague electrolytic ground to the chassis and two light coloured wires coming from the other end, one going to the base of the existing 16 mfd electrolytic and the other going to a mass of wires attached to a terminal strip.

    The 16 mfd cap has, besides the light coloured wire, two additional red wires, one going to the same terminal strip as the Sprague and the other going the rectifier.

    I’m aware that if I get the polarity wrong I could totally mess up the radio so I’m appealing for some assistance as the how to rewire the – and + of my replacement electrolytic capacitors. I take no offence to any suggestions either, if there was Radio Restoration for Dummies I would be at the front of the line buying it!

    #15892
    Les Dickson
    CVRS Member

    Hi Robert. The yellow Sprague cap on the underside of the chassis with three wires contains two 10 mfd capacitors, each with a red wire on the positive end and a shared black common or ground. it’s not a 20 mfd cap. It seems that someone put that in to replace both original caps but it looks to me like there are two problems with that. 1) 10 mfd is not an adequate replacement for the 16 mfd. 2) they didn’t remove the original 16 mfd cap. Where the wire from the Sprague connects to the bottom of the original 16 mfd it’s simply making a connection with all the wires that should be part of that circuit. From the 16 mfd one wire should lead to your rectifier tube 6X5G and the other wire should lead to the speaker field coil.
    I hope that’s helpful.

    #15893
    robert clausen
    Forum Participant

    Thanks Les
    The one red wire goes to my rectifier while the other goes to the terminal strip. Whether that one eventually leads to the speaker field coil I’m not able to tell. I’ll enclose a better photo because I appreciate your help but I’m still in the dark as to how to wire my new caps.

    #15896
    Alistair Thomson
    Forum Participant

    It looks like Les is correct about the original cap still being in circuit. But I’m confused about the short red wire going to the 6F6. It seems to be connected to pin 8, the cathode, but the schematic shows it apparently connected to pin 4.

    #15897
    Sterling Spurrell
    CVRS Member

    Could someone post a schematic that they are looking at? Thanks

    #15898
    robert clausen
    Forum Participant

    Unfortunately I don’t know how to post a link and the schematic I received from radiomuseum expired after 24 hours. I will enclose a screenshot, I hope it helps.

    #15900
    robert clausen
    Forum Participant

    In my first post I mentioned that the one red wire from the 16 mfd cap went to my output tube 6F6. I was mistaken it actually does go to the rectifier tube.

    #15901
    Les Dickson
    CVRS Member

    Hi again Robert. Hopefully you have a dim-bulb tester set up before you fire up your radio. You should be able to ground both replacement capacitors to the point where the original caps were grounded. In some radios the caps were not grounded to the chassis so I find it a good practice to always ground the new caps to wherever the originals were. Then I’d suggest you remove, or disconnect, the one remaining original cap from the circuit – it’s not a good idea to leave the old ones connected. For the positive ends of the replacement caps you can connect them to where the leads of the Sprague capacitors now lead – being sure to get them to the proper 10 mfd and 16 mfd locations. And of course remove the Sprague.

    #15919
    Radio Nut
    Forum Participant

    Robert is there a radio club in your area. I am sure if so someone would be glad to help you out with the way it goes.

    #15931
    robert clausen
    Forum Participant

    Thanks all for the assistance. I did what Les mentioned and the Westinghouse is working wonderfully.

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