back to the AGC, was Re: TTL 7400's Available

On 3 Jan 2007 at 8:14, Allison wrote: If you read the AGC construction documents carefully, the RTL element used was a dual 3-input NOR. Now, I don't expect that this was used to the exclusion of all other active discretes, just that the circuit mentioned was probably the only digital IC type used. In 1968 I was already building circuits using reject 923 flatpacks to build my registers. No one told me how to deal with them physically, so I simply etched a single-sided PCB with solderable pads on each one and wired the pads to one another using (gasp) #26 enameled magnet wire. It worked well enough to satisfy my curiosity. But no matter what was available, the AGC had to be constructed of something that could be qualified for service--and using a single logic type undoubtedly simplified the process by limiting the active logic elements to a single known type. What really impressed my about the AGC design was the the thought that went into the modulatrity of the logic blocks--and that the whole thing took up only 2 cubic feet. Cheers, Chuck