Re: MK14 memory upgrade
Mind reader! That's almost simple enough to try on a breadboard/plugboard if the leads are are kept short, just to try the concept of a plug on 'Ram Pack' for the MK14.
I was thinking of something similar but using a single PROM as the address decoder - I have quite a few Philips 82S185 (1024 * 4-bit) PROMs looking for something to do. Obviously yours, using discrete TTL, would be more build-friendly and would avoid the question: Would a PROM be responsive enough in this application?
However I do remember occasional forum user gertk64(?) mentioning that he had tried a 6116 mapped into his MK14 replica while he was waiting for the proper RAMs to arrive, but it didn't work for him for some reason - unfortunately I don't think he came back with a theory about that.
I think where there is the intention for this to go between the MK14 and the VDU (and all sort of interesting things besides) you would probably end up being obliged to buffer the buses and control signals to whatever extent possible without making it too complicated.
However, it may be worth building it as simply as possible and just turning it on with crossed fingers. I'm sure a lot of people mapped 1.5K onto their Issue Vs back in the day using the minimum possible hardware.
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