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Ford F-1540 Questions
#21

F-1540,
RodB commented, I saw the words "common positive" on the electrolytic can. Did you join the plus wires of the caps and connect them to ground?

I sure hope you didn't connect the positive leads to ground. The caps will likely explode!
Take a look at the schematic. Counterintuitively, the NEGATIVE lead of the 8uf cap is connected to the positive ground of the radio. To the radio chassis, that is. The chassis IS negative relative to the cathode of the rectifier tube, where the positive end of the cap connects. By more than 200 volts! The can itself rests on the case and is grounded also.
The 2 "common positive" leads of the 4uf and 8uf caps are connected to each other and to the cathode of the rectifier tube. In any event, neither contact on the bottom of the cap can connects to ground. Only the case itself is grounded.


Messages In This Thread
Ford F-1540 Questions - by F-1540 - 12-26-2023, 10:55 PM
RE: Ford F-1540 Questions - by RodB - 12-27-2023, 12:25 AM
RE: Ford F-1540 Questions - by Tim Tress - 12-27-2023, 12:44 PM
RE: Ford F-1540 Questions - by Chas - 12-27-2023, 01:55 PM
RE: Ford F-1540 Questions - by morzh - 12-27-2023, 03:19 PM
RE: Ford F-1540 Questions - by Chas - 12-27-2023, 03:35 PM
RE: Ford F-1540 Questions - by morzh - 12-27-2023, 03:50 PM
RE: Ford F-1540 Questions - by F-1540 - 12-27-2023, 06:18 PM
RE: Ford F-1540 Questions - by morzh - 12-27-2023, 07:11 PM
RE: Ford F-1540 Questions - by David - 12-27-2023, 07:27 PM
RE: Ford F-1540 Questions - by David - 12-27-2023, 07:29 PM
RE: Ford F-1540 Questions - by Chas - 12-27-2023, 08:59 PM
RE: Ford F-1540 Questions - by F-1540 - 12-28-2023, 11:10 PM
RE: Ford F-1540 Questions - by Chas - 12-29-2023, 12:30 AM
RE: Ford F-1540 Questions - by David - 12-29-2023, 03:49 PM
RE: Ford F-1540 Questions - by F-1540 - 01-13-2024, 06:04 PM
RE: Ford F-1540 Questions - by RodB - 01-14-2024, 10:57 AM
RE: Ford F-1540 Questions - by F-1540 - 01-23-2024, 02:28 PM
RE: Ford F-1540 Questions - by RodB - 01-23-2024, 05:54 PM
RE: Ford F-1540 Questions - by F-1540 - 01-23-2024, 06:33 PM
RE: Ford F-1540 Questions - by fenbach - 01-24-2024, 12:05 AM
RE: Ford F-1540 Questions - by radiorich - 01-24-2024, 09:38 AM
RE: Ford F-1540 Questions - by Chas - 01-24-2024, 01:28 PM
RE: Ford F-1540 Questions - by F-1540 - 01-27-2024, 10:00 AM



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