whistling mac plus

From: Marion Bates <Marion.Bates_at_Dartmouth.EDU>
Date: Tue Oct 20 22:07:41 1998

--- SUPRDAVE_at_aol.com wrote:
i fear it's probably that infamous cold solder joint issue. i'm
looking at a spare mac power supply board; does anyone know any exact
locations of common solder joint failures? finally, if i do touch up some
contacts with a soldering iron, MUST the high voltage lead be discharged? i'm
hoping i can just remove the protective cardboard cover, reheat the solder
joints and not even go near the HT lead or tube at all.
--- end of quote ---

In my experience, the C-shaped ring of joints corresponding to the flyback transformer go bad pretty often. Also, I've re-soldered them before without discharging the high voltage lead, and everything's been okay afterward, but maybe that's just lucky. If you DO discharge it, do NOT ground to the chassis -- I read once that the logic board components are too delicate to share ground with a jolt like that. Use the screw on a wallplate or something instead.

Good luck!

-- MB
Received on Tue Oct 20 1998 - 22:07:41 BST