Have a automotive battery charger/car starter which doesn't work quite
right. Won't charge the battery up more than half-way, and I find 5.5VAC
rather than the expected DC of 1.5V (+/-) applied to the gate of the SCR
that seems to drive the whole thing (NTE5539). My suspicions point to
what
appears to be a pair of diodes mounted on the massive heat-sink inside
(see
jpegs posted to a.b.s.e. Sorry for the poor focus in the up-close, but
that's the
best my camera will do). The two clips are connected. My
DMM, using the diode checker, registers .879v one way (neg probe on DUT
and
pos probe on heat sink), and .397v the other way. I am thinking this is
some sort of bridge rectifier? And maybe the previous owner of the
machine
hooked it up to their car backwards at some point? I am going to
disassembel the device in question just to make sure it is not something
else, but wanted to ask if anyone else had any ideas on what it is...
Any
help, or suggestions, are more than welcome and eagerly sought.
Thanks,
Dave
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