Thread: Battery charger
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Old November 18th 08, 04:09 PM posted to rec.radio.amateur.homebrew
Grumpy The Mule Grumpy The Mule is offline
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First recorded activity by RadioBanter: Sep 2008
Posts: 87
Default Battery charger

Howdy,

Geez... I read this and it confused me. I haven't been
sleeping much and shouldn't post late at night.

The easy fix is to use an emitter follower circuit
where the the constant current load is connected to
the emitter. If you put the regulator in the Positive
side lead use an NPN.

In my instance the current regulator's pass transistor
is in the negative lead so the heatsink is at the same
potential as the vehicle chassis. No insulating hardware
is required.


73,
Grumpy

Grumpy The Mule wrote in
:


There is an easy fix if you use a PNP pass transistor. Clamp
the base at 13.6V plus a base emitter drop, say 0.8V, the output
can't rise higher than the float voltage.