Locked SY-41CL back to life

[Monte Dalrymple]

Before I close up a CL conversion (and I've done this at least ten times) I've always cleaned the places where pressure is required for contact with DeOxit before putting the machine back together. I also try to "squish" the zebra connectors orthogonal to the direction of pressure to make sure that they have the best chance of actually being under pressure. This is especially important for the ones with foam-looking stuff in the middle. Also, if you have the foam ones, the plastic piece holding them in place wraps around the ends. This will be a problem because of several small SMT resistors that happen to be placed where they will hit the plastic fingers. So these wrap-around sections need to be cut off. I wasn't aware of this variant when I designed the CL board, or I would have tried to place things differently. With the other type of zebra connector, be very careful when cleaning them. It is easy to detach a wire or two and create a short between adjacent signals. this is very hard to see, at least with my aging eyes. I've only soldered one machine, using 30-gauge wire-wrap wire. And that was only because I had used the board for development and needed it outside of the calculator body.

Monte