The RAM is from Hynix:
HY62CT081ED-70C = 70ns refresh
The RAM is from Hynix:
I don't think so, but it may affect timings elsewhere that cause problems.
The -70 actually refers to the access time in nanoseconds, that is, how quickly it can make data available (reading) or accept a write. The chip may actually be able to operate quicker, but this is the maximum amount of time that it would take.
No.
This is exactly my wiring.OR
Pin 20 in the socket. Only a capacitor should connect to here. This pin must NOT be connected to 0V/GND.
Pin 22 lifted and wired to pin 14 (which is 0V/GND).
That's way too high. Please be careful as there's only a 680R resistor between your capacitor to ground and the /RAMCS pin on the ULA.