[sdiy] Starting my next major project...

Grant Richter grichter at asapnet.net
Wed Jun 26 18:42:44 CEST 2002


This is an excellent method of assembly, and will save a great deal of time.

> I simply don't use PCB for jacks, but there are alternatives.
> Use pots with longer shafts, so when PCB is in distance from
> panel determined by jacks,

This is how Serge built his early modules. He used nylon bushings at the
front to remove the wobble from the long shafts.

In Wiard modules, each potentiometer is it's own subassembly with a 3 pin KK
connector. This was done so the pots can be replaced in 3 minutes flat
without soldering equipment. I have a college student friend assemble them
by the hundreds.

The disadvantage with the PCB mezzanine board approach, is the entire
faceplate has to be disassembled for service. Don't forget that everything
eventually needs maintenance.

> One for pots and
> circuitry, second for Jacks and connect the two with ribbon
> cable.

This is how Buchla did most of his modules. The Music Easel and 266 SOU (for
example) have a PC board directly behind the faceplate that all controls
mount to, these are connected to the circuitry with dip jumpers. The
disadvantage is capacitive coupling in the ribbon cable, you have to think
about placement, and not run your module input right next to your module
output. Or put ground lines in between.

> Or another idea, the one I use for toggle switches. I mount
> them on PCB (and panel, as they are separated only by 0.5mm
> insulator) and connect to PCB pads with solid wire. Works
> good so far, and can be easily done with jacks also.

Buchla used this technique for the keyboards where the faceplate is printed
circuit material, the parts mount to the PCB and connect to large pads with
solid wire.

All of these technique are known to be reliable, since there are 30 year old
modules built this way and still working well today. Once you eliminate
point to point panel wiring, you will never go back!





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