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Schematic diagram of one version of the Electronic Voltage Regulator
Copyright, 2012, R. Fleischer


R1   330 ohms resistor
R2   270 ohms resistor
R3   470 ohms resistor
R4   1.5K ohms resistor
R5   1.2K ohms resistor
R6   100 ohms resistor
P     100 ohm potentiometer
C1, C2, C3     100nF ceramic capacitors
Q1,Q2      BC327 transistor

Q3     BD244 series transistor.   BD244 rated at 45V; BD244A rated at 60V; BD244B rated at 80V, BD244C rated at 100V.  Rating of all are 6 amperes and Vce-sat is max 1.5V  ***Snowbum says that if replacing Q3, a higher current rated transistor is a good idea, such as 10 ampere.  A lower Vce-sat would also be helpful for longer life.

D1     1N4148 diode
D2     BZX6V2 zener diode, 6.2V
D3     1N4003 diode, can substitute 1N4004, etc.
D4     Diode has no markings, but a 10A, 50V or higher rated diode should be OK.

D+   Regulator input, from output of diode board and to alternator telltale lamp.

Df   Goes to one brush/slip ring of the alternator rotor.

D-    Goes to the other brush/slip ring of the alternator rotor, and to bike ground via a brown wire.

10/15/2012:  Add QR code, add language button, update Google Ad-Sense code.
04/27/2016:  Update meta-codes & layout, add edit script.
01/13/2017:  Update meta-codes and scripts.  Improve readability of article. Improve parts descriptions.  Fix fonts, colors and layout.

Copyright, 2012, R. Fleischer

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Last check/edit: Wednesday, January 17, 2018