Any *really* homebrewing going on?

From: Gary Oliver <go_at_ao.com>
Date: Sat Oct 3 18:27:09 1998

Cool!

I've also harbored a secret (it's out now) desire to build a PDP-8
from scratch - and I'm talking "straight" 8 here. Transistors
of the 2n2222, 2n3904/3906, etc. varieties are SO CHEAP these
days (at least in quantities) that the "semiconductor" content
of a straight-8 should run less around $100. It's only a "few
hundred" circuit boards...

However, I'm derailed by the "interconnect problem." Although each
circuit board will only have a few dozen components (well, the
flip-flops are a "bit" (pun intended) more complicated) the PC BOARD
is going to set you back a few bucks. And then add the interconnect
to the "back plane" or "panel" where the REAL logic is implemented
(all that wire-wrap.) So a couple of dollars of parts on the board
goes up to several dollars by the time you add the board and
connection.

One of my current "designs" involves using DB-25 connectors
(they have become rather cheap due to volume use in the PC
industry - don't know how long that will last, though) and building
the back panel with lots of posts connected to the mating connector
and then wire-wrapping on those posts. Better yet, using wire-wrap
DB-25s on the back panel, but I haven't found a good (read 'cheap')
source of wire-wrap connectors, yet. The connector on the circuit
board (plug in module) will cost around 30 cents. A wire-wrap
connector for the back panel costs from $3.00 to $10.00 depending
on supplier and quality.

At 07:09 PM 10/3/98 -0400, you wrote:
>
>< and peripherals together to make a (shudder) PC. I'm talking about
>< *REAL* iron (or aluminum.) Starting from basic relay, transistor, or I
>
>Lessee, I do much of my own bent metal, cases cost! I've been building
>hardware for far to many years to count.
>
>< (SSI or MSI only!) and rolling a machine the "hard way." Recreations o
>
>Even the 8008 was considerd LSI!
>
>< old machines (i.e. building your own PDP-1) would make a very
>< interesting discussions.
>
>Difficult as well as where down one get core these days?
>
>I'd love to build a PDP-8 from the ground up using current (nonFPGA)
>tech. For the moment I've building up a z80/s100 crate and doing a
>z280s/CPM project for my self.
>
>
>Allison
>
Received on Sat Oct 03 1998 - 18:27:09 BST