I have a CASE trencher (CT ) and the regulator=20
failed.
The CT has a 12V battery to start the engine.
There are two leads coming from the flywheel.
I believe they are attached to a coil that is=20
activated by a passing permanent magnet. I have
connected a full wave diode bridge to the leads and
put a cap across it.  I measure 33VDC ( no load ).

I put together a circuit where a resistor drives=20
a 14V zener to ground. A 2N3055 transistor has it's
base connected to the 14V.  The collector goes to the
fullwave bridge.  The emitter goes to the battery.
This circuit worked fine when I tested on the bench.
The output at the emitter ( under load ) was 13.4 V.
When I connected it to the CT , the zener burned up.
I have not yet investigated what may have happened.

I can think of many ways I might proceed.
I would invite comments on whether I should stick with
a linear regulator approach or do some sort of switching
regulator ?

( Olin does not have to explain to me that I am a=20
congenital idiot .... I concede the point  )

Best
Gus in Denver     99gus
--=20
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