Replica MK14

My replica MK14 front viewMy replica MK14 top view

My replica MK14 is based on the version 5 original, this version incorporates the revised address decoding so that the PROM only appears once in the memory map leaving space for e.g. the VDU board.

In addition I have added a link and pull-up resistor (R16) to NENIN for use with the VDU board (cut the link and fit the resistor) and a pull-down (R17) on SENSE-A which enables the use of the later version SCIOS (either fit the resistor or a wire link).

There are various options for the keypad:

(replace xx in switch part numbers with your colour option)


A further option is to fit a keypad overlay, this uses 12x12mm 4.3mm high tactile switches (avaliable on eBay).


MK14 Keypad Overlay   MK14 with keypad overlay


The keypad overlay is avaliable from Ian Reynolds: 'Realtime' on the UK Vintage Radio forum or '55theparade' on eBay.



(On some batches of boards I have had problems with the positioning holes for the power connector J3 being incorrectly plated through resulting in a short, the fix is simple just drill them out to 1.3mm)


Bill Of Materials


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