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Old 10th Dec 2020, 8:58 am   #153
SiriusHardware
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Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 7,057
Default Re: I found it! A very sorry looking MK14.

The mods for removing the unwanted PROM images 'stole' one of the two inverters which were originally in series on the input of the reset circuit, so the reset -switch- circuit is then modified to take the reset-circuit input high when pressed rather than low.

The issue VI keypad connector is the same as on all original MK14s, thankfully, except that one of the two 0V fingers at the top end has been repurposed as an external reset input. Since external keypads don't usually use those top two connections, that would not usually be a problem but maybe one of your many add-ons picked up a common 0V from there?
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