As follow up to earlier questions, the 4702A and 8702A were the MCS-4 and MCS-8 equivalent numbers for the 1702A. Electrically they are identical.
Martin Eberhard's ME 1702A programmer is excellent and works very nicely.
Another alternative which is sleek (but much tougher to construct) is Matthew Millman's 1702A Arduino Shield. Construction is not for the faint-of-heart but it's amazing to have a 1702A programmer that is not much larger than an Altoid tin! http://tech.mattmillman.com/projects/a-compact-programmer-for-1702a-eproms/
As I recall, there were differences in things like the tolerance of the voltages and currents they would operate over but in a generic sense they were the same.
I've been meaning to setup a threshold adjustable reader my self. I have a EPROM that has serious bit rot but I'd like to get the data from or at lest what is left. It contains the fourth EPROM data of the 4004 assembler, running on a 4004, that Tom Pittman wrote for Intel. ( he also wrote the 6502 tiny basic ).
PMOS are suppose to be hard pull up and soft pull down. Kind of different than ttl.