Wagner WAC40

[Joshua Rice]

> Very interesting looking.  I can't quite make out what is going on in that rectangular area where all the wires terminate, labeled 0-15 and A-R.  Are there diodes there?  Anything on the other side of that board?

Nothing but traces on the other side, though you’re right on them being diodes.

> The large cores with all the wires are remisniscent of core rope ROM.   If so, I wonder if it's AGC (Lincoln Labs) style, EL-X1 style, or a scheme different from either of those two.

It’s definitely some form of core rope ROM. 

Interestingly, the ferrite rings are built in pairs, with a "selection" coil wrapped around both, joining them. Therefore (i assume, i’m really no expert) they’ll be a positive pulse induced when passing through one coil, but a negative pulse when passed through the opposite coil. This probably helps in differentiating beween a 0, a 1, or a NULL state (ie 0v). 

I have no idea if that correlates with any particular format of Core Rope, but as far as my eyes can tell, that’  how the core rope is woven and functions.

I think, though again i’m no expert, that the termination points indicate that this read off a 16 bit word in parallel, instead of working in serial to build up a word. Therefore, it contains 16 (pairs of termination points) x 64 (pairs of “selection” rings) = 1 kiloword of storage. I may however, to quote Bob Geldof, be talking bollocks.

Josh Rice