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Automotive 6 Volt Generator Transistor Voltage Regulator


New Member
Backwards on the output side. So, opening the MOSFET "disables" the gen field. Thanks for the update.

Yes, I didn't have any 50 ohm resistors. So, the 47ohms had to replace. I should have labeled the picture with the functions. Everything runs linearly right to left except the MP350 output which runs to the IRF540 on the base. I tried to keep everything inside the sealed cap to keep it dry. Hope it doesn't make the MOSFET and the 80A rectifier run hotter.



Active Member
Probably be ok, the MOSFET's Don't get hot unless they are 1/2 way on. The Cutout Diode will get very hot with the headlights on but if it's mounted against the metal with a heat sink insulator it would track a few degrees over Generator Temperature, I have seen mine hit 250'F and still work fine. I think the The 82CNQ030 center tap Schottky rectifier module Cutout Diodes have a 150' C rating It will need to dissipate about 15 watts. IR 82CNQ030.
P.S. You can find them on e-bay for about $5 each plus shipping.
Last edited:


Well-Known Member
Most Helpful Member
Danwvw Dan. You developed a pretty good following for this "bumpy" ride of yours. Your schematics remind me of the Radio Shack ones. They don;t have cartoons like Tektronix does and there aren't any Easter Eggs. e.g. When you take the regulator apart, there it is, "a schematic" inside.

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