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Tim Stinchcombe

A-163 DC-Coupled Output Modification

As mentioned on page 4 of the A-163 Owner's Manual, if you want to divide-down slowly-changing signals (a clock-type signal, say, as opposed to an audio-rate one), all that needs to be done is to short out capacitor C7. This is located between the big 'PIC' chip and the front plate, and is marked 'C7 2u2' on the silkscreen. There is plenty of space for mounting a new 'on-off' switch on the front plate, and this is simply soldered across the legs of capacitor C7: with the switch 'off', the module operates as before and the output is AC-coupled (for audio-rate signals); when 'on', the cap is shorted and the output is a 0/+5V rectanglar wave.

[Page last updated: 14 Dec 2009]