11-27-2020, 09:54 PM
Those capacitors are not original to the radio. The original cans used the outside of the can as a contact either to ground or to the center tap on the transformer depending on which one you are wiring. As Mike points out the insulating sleeve keeps the can (and metal tab that was on the side of the can used to connect a wire to) away from the chassis. In your case, the new caps may have the negative lead as a wire rather than the can itself.
schematic ( http://www.nostalgiaair.org/pagesbymodel797/M0013797.pdf ) #41 and #54 connect to chassis ground and # 56 connects to the center tap of the transformer secondary. See where the leads are connected now as a guide but check with the schematic as well. There's a picture of some original caps in the post https://www.philcoradio.com/phorum/showt...#pid148593 so you can get an idea of what they looked like. The upper photo one has been cut open and gutted to place a modern cap inside it. The lower photo is after it was put back together and is what the original look would be.
schematic ( http://www.nostalgiaair.org/pagesbymodel797/M0013797.pdf ) #41 and #54 connect to chassis ground and # 56 connects to the center tap of the transformer secondary. See where the leads are connected now as a guide but check with the schematic as well. There's a picture of some original caps in the post https://www.philcoradio.com/phorum/showt...#pid148593 so you can get an idea of what they looked like. The upper photo one has been cut open and gutted to place a modern cap inside it. The lower photo is after it was put back together and is what the original look would be.