Hi JIM.

22-Dec-02 19:35:00, JIM HOLSONBACK wrote to ALL


 JH> Hello, ALL.

 JH> I have (or had) this "Auto Stereo Home Adapter" box, rated at
 JH> 115VAC, 12-14VDC, 3 amps continuous, 5 amps switching.

 JH> I ended up blowing it up - - I'll tell about that later.  Took it
 JH> apart, and the only thing in there which could possibly be a
 JH> rectifier is this lightbulb-looking thing, with 2 bare leads out
 JH> of the bottom of the glass, and wired to the circuit board.

Circuit board, I guess that means it's not old enough to have a
metal-oxide rectifier stack in it   (looks like a buinch of metal plates
with a brass rivet throught them and 4 wires attached)

 JH> I've seen one of these before, now over 40 years ago, and it was on a
 JH> little 6V trickle charger, and I ended blowing that sucker up too,
 JH> while I was still in highschool.

That one wasprobably a real light bulb.  they make a handy current limiter
for trickle chargers.

 JH> My questions - -1.  What the heck are these bulb things, and how
 JH> much would a replacement for the unit at hand cost?

the cost is small, the trick is getting the right one....

 JH> 2.  How can a rectifier with only 2 leads give good enough DC to
 JH> run an auto stereo back in the home, without a lot of hum.

I don't think it can, keep lookimg.
trace the transformer secondary circuit, it's gotta go to the rectifier
or possibly the on/off switch of fuse)

 JH> 3. Should I pitch the thing, or could maybe some large diode or
 JH> diodes be added, which would make it useable again?

if it's got a dead lightbulb it needs a new one,  check the one you have for
clues. for low voltage ones the colour of the glass bead on the filament
supports indicatees the voltage.

 JH> FWIW, in desperation, after probs with the riding mower, I used
 JH> this unit for a battery charger.  It worked OK, and put some
 JH> charge on that there lead acid battery, but I blew it up and 'let
 JH> some smoke out" when I tried to crank the mower while this
 JH> makeshift "charger" was still attached.

you could have cooked the transformer primary, (I reecently did that by
accidentallt to tow of my plug packs)

OTOH that thing could have a switching reguilator that's been cooked,
(what all is on the circuit board?)

 -=> Bye <=-

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