Yep, that’s 74XX TTL logic around the edges. Looks like mostly 7402 and 7403 chips, which are simple quad NOR and NAND gates. In other words, only 4 gates to a package, compared to billions in today’s chips!
I’m sure it’s not 19K words – memory is always going to come in a power of 2. I think 8K x 19 means 8192 words of 19 bits each – probably 18 data bits and one parity bit. With two boards that could give you 36 bit words. I’m so glad the computer industry has since standardized on 8 bit bytes – what a mess it was with the different word lengths of early machines! Maybe the 175 refers to the access time of the memory, perhaps 175ns? That’s kind of a guess on my part, but I can’t think of what else it could be.
I can’t quite tell – is the core memory itself mounted on a separate clear panel above the PC board? It looks like it might be ~10mm above the main board, supported by posts around the edges?
Could you email me the full size photos? I’d love to get an even closer look. Very cool that you kept this.
I wonder what “hand wired in Singapore” means. The core memory itself certainly looks much too dense to be hand wired, though I know earlier versions of core memory were hand wired (but much less densely. The PC board looks wave soldered. But maybe the connections between the PC board and the daughter board are done by hand.