Richard Holder wrote:
>
> I checked the C terminal. Disconnecting it does
> eventually kill the charging but not very quickly, so
> disconnecting the C connection via a crowbar won't work.
The delay is because a capcitor has to first discharge internally;
grounding won't do that..
> So I suspect your "earthing" of the C
> terminal was really just disconnecting it.
Thus correct, because of that blcking diode. What grounding will do is
prevent spurious noise from triggering the sense circuit, which is a
hair-trigger "Darlington amplifier," though a rather low input
impedance for that sort of problem.
> I actually looked at the circuit board of my original
> (now re-installed) regulator and saw three possible
> sites for dry-joints.
Anything's possible. It looks hand-soldered, but by someone "on a
mission." And apparently still did a poor job where it really mattered!
Reg,
Fred F.
|