6 Mar
2002
6 Mar
'02
11:13 a.m.
On Wed, 6 Mar 2002, Ethan Dicks wrote:
Peter Wallace
--- William Donzelli <aw288(a)osfn.org> wrote:
I _think_ I have some 7400-series chips from 1967, but no earlier. They'd
be in a PDP-8/L if, in fact, I am remembering correctly.
They are 14 pin DIPs in shiny black epoxy. RTL I believe.
I was
just reading a bit on TTL while looking for something else.
In 1965 a 7400 gate was $20 and Candy bars 5 cents.
Probably not 7400 series (earliest 7400 series I have are from late
1968). There were a number of logic families that were
out in the mid-1960s.
Indeed... I am looking for some (and not expecting to find any) to
build a replica of a DW08, DEC's pre-TTL TTY interface made from W-series
and R-series logic. The W706 and W707 boards use a Motorola logic family
with 3 digits, not 4. The schematic for the W707 transmitter shows...
1 x MC799P "Dual Power Buffer" ('P' for Plastic package, 0C - 70C
rated)
8 x MC724P "Dual J-K Flip- Flop"
5 x MC724P "Quad Input Gate" (NAND)
5 x MC789P "Hex Inverter"
GND is on pin 4, Vcc is shown to be +3.6 VDC on pin 11. The schematic also
suggests that they are 14-pin ICs, but no way of telling if they are DIP or
some other packaging (but the mention of a plastic package is a hint).
I have to say that I have been previously unaware of any logic family that
used +3.6V for Vcc. Anyone have any info from 35 years ago?
Fairchild RTL uLogic (914 dual 2 IP NOR, 923 JK FF,913 D FF etc (memory
failing...) -- all 8 pin TO5 cans or epoxy equiv...
also use 3.6 V
Yes, in 1965 I can believe $20 per chip!
And then, ten years later, 19 cents per chip...
Thank you, Gordon Moore.
-ethan
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