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Mark Zacharias Mark Zacharias is offline
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Default Ping Jim Yanik Tek 365

"Jim Yanik" wrote in message
4...
"Mark Zacharias" wrote in
.com:

Hey, Jim.

Long story short my 465 quit a while back. No trace at all, even with
the beam finder. I got tired of looking at it sitting there, and
decided to poke around and see if I got lucky. Well, I found a missing
-8v line which, when jumpered in, seems to restore normal function.
That line draws about 600mA. Cannot readily access the bridge
rectifier CR1569 to remove and test out of circuit - I suspect it is
(partially) open.

Is this a common problem? Seem like I'm on the right track?

Thanks!

Mark Z.




I had to replace many bridge rectifiers in the power supplies.
152-0488-00,IIRC,and 152-0462-00;the bigger bridges.

my shortcut;
flex the old bridge back and forth til the leads broke,then use a
soldersucker to remove the leads remaining in the holes.
then stand the new bridge off the board about 1/4 to 3/8" so you can
solder
the leads without having to remove the MB. watch polarity!
I'd often bend the bridge leads 90deg then trim to length and solder into
the PCB,for case clearance,particularly on the big bridges.

another worry is filter caps leaking electrolyte and eating through PCB
traces on the back side of the mainboard. I used to have to do a lot of
big eyelet setting(for big filter caps) and track repairs;
One boss preferred to not replace PCB's if avoidable;he'd rather a tech
put
in many hours filling in holes with epoxy,setting eyelets and track
repairs.

One note;some filter caps in the PS used the can (the 3 or 4 negative
pins)
to connect parts of the circuit,IOW,you had to solder ALL the cap pads,or
if substituting an axial leaded cap(many customers would sub in any old
cap
from their junkbox),bridge the can pads for continuity.

BTW,I figured you were talking about the 465,not a "365"(no such animal).
8-)
No problemo!

--
Jim Yanik
jyanik
at
localnet
dot com



Thanks Jim. I figured you'd know what was up with these. That bridge is
nestled down pretty flush with the board; I might opt to just get the board
lifted up some for access, especially in view of the possibility of corroded
trace(s).

Thanks again!

Mark Z.