[sdiy] Repairing the Serge, part 1: Cleaning flux

[Paul Perry]

At 12:23 PM 22/08/02 -0700, Jim wrote:

>These boards are a rat's nest of point-to-point wiring, and both sides of
>all boards are covered with orange crystals that I suspect are decades-old
>flux. So my first step will be to clean this crap off, so that I can scan
>the boards for possible reverse engineering or at least reference.

My own preference is to touch as little as possible.
I have never seen a schematic successfully derived from a scan.
You just have to make sharp points for your multimeter (I solder safety pin
points on) and prod away.

>I'm planning to clean them by 1) scrubbing with a dremel tool with a
>plastic brush; 2) dousing liberally with rosin flux remove, and 3) dousing
>even more liberally with distilled water. 

Jim, it is better to measure signals while the unit is trying to work, and 
keep going until 'something strange' appears. It wouldn't hurt to have a 
copy of "Troubleshooting Analog Circuits" by Robert Pease.

Once you get it going, THEN you can remove flux!

paul perry Melbourne Australia