Tony Duell sez...
>
> > > Is the 7474 a 'dog'? I've know a few TTL parts that were pretty bad,
> > > mainly counters though. But a latch?
> >
> > This reminds me of a similar problem in the JC80 systems, where 74170
> > chips would fail more often than anything else. I'd sure like to know what
> > the cause of that was...
>
> I can remember replacing many 7474s in the RK11-C when I was getting that
> going. Oh, and a 7482 adder, which was impossible to find [1]...
>
> More recently, I've had a lot of 74Hxxx parts (and yet more 7474s) fail in
> HP98x0 calculators. I guess after 30 years I can't really moan...
>
> [1] I do mean _iompossible_. I ended up using part of a 7483 that I stuck
> to the flip-chip PCB dead-bug style and wired to the holes where the 7482
> should have been. Runs fine...
Bzzt. Wrong. (First, you probably mean "_impossible_" :-)).
I just bought 5 of them for US$1.25 (or so) each from
Gateway Electronics. Along with spare 7453, 7460, 7440, etc. I think it's
something like "gatewayelex.com".
Cheers,
-RK
--
Robert Krten, PARSE Software Devices +1 613 599 8316.
Realtime Systems Architecture, Consulting and Training at www.parse.com
Looking for Digital Equipment Corp. PDP-1 through PDP-15 minicomputers!
Received on Thu Jul 17 2003 - 10:55:47 BST