Testing Power Supplies! Re: Norsk Data Nord-10/S restoration effort on the way!

[William Maddox]

Paul Koning wrote:

>  Tore> But access to a complete array of spares if nessecary. Oh, and
>  Tore> the CPU is built in TTL logic, so no hard-to-get spares.
> 
> TTL is getting hard to find, especially the more obscure types such as
> 74S series.  (And if the book says they want 74S, it's quite possible
> no other variant will work...)
> 
>    paul

I thought that 74F series parts were generally replacements for 74S
parts.  Is this incorrect?  A more serious concern is that the parts
that have been recently produced seem to be simpler glue logic, bus
transceivers, etc.  Many of the nice functional blocks used for building
CPUs were dropped from manufacturers catalogs years ago, and many were
never even offered in the more recent logic families.  Take, for 
instance, the 74172, an 8x2 dual-ported register file used in the Data 
General Nova 2.

--Bill