I was shuffling through some papers last night and stopped for a moment to read the two
copies of "Altair Notes" from
1975/76 in my possession. (Altair Notes was a newsletter for Altair owners. They're
rather amusing as they have articles
written by Bill Gates and Paul Allen from the period when (if I have it correctly) they
were working for MITS.)
(Also ran across an article I cut out of Technology Illustrated (Sep 1983) years ago about
the inception of the Boston Computer Museum. I sure hope they weren't butchering their
artifacts to add the christmas tree lights mentioned in another thread.)
In one of these Altair Notes is a small blurb and picture of a new product from MITS. For
what it is worth (which isn't
much, considering how little it says about what the board actually does) below is the
text. The picture matches your (Brian's) picture, but the mentioned "parts
layout" is not present.
I'll speculate the "$500.00 savings" mentioned is in relation to a more
expensive option from Teletype providing the
equivalent/desired functionality.
(excerpt from Altair Notes / March 1976):
-------------------------------------
New Products
Teletype Call-Control Kit
The MITS Teletype Call-Control Kit provides a much lower cost and faster way to get a
teletype into your system than was
previously possible. MITS has made an agreement with Teletype whereby the fully assembled
mechanical portion of the Teletype
will be shipped directly to you from Teletype Corp. and the PC board Call-Control Kit will
be shipped from MITS. Starting in
May, delivery time should be a couple of weeks as opposed to 4 to 5 months.
There are three Call-Control Kits available: 88-TYR which is supplied with the Teletype
printer only, 88-TYK which is
supplied with Teletype Model KSR-33 (printer and keyboard), and 88-TYA which is supplied
with Teletype Model ASR-33
(printer, keyboard, paper tape punch and reader). All three kits use the same basic
printed circuit board (see parts layout,
this page). All you need to do is assemble as much of the PC board as applies to the model
of Teletype you have purchased,
mount it to the Teletype chassis, and plug it in.
The PC board for the 88-TYR (printer) kit has a power switch, two fuses, a simple power
supply and the receive circuit for
20mA current loop. Interconnect plugs and mounting hardware are also provided.
For the 88-TYK kit, a relay for line-local switching, a connector to the keyboard, and
some transient damping circuitry
are added.
For the 88-TYA kit, all of the above is included with the addition of another simple
power supply, connections for the
paper tape reader, and a circuit to control the reader by program control.
That's all there is to it. The most complicated part of the assembly is connecting
wires from the line-local relay to the
PC-board. The 88-TYA kit should take only 3 to 5 hours to complete. At $500.00 savings,
that's $100.00 an hour for your
time.
-------------------------------------
Brian Knittel wrote:
Hi,
For those of you who asked to see the MITS
Teletype Interface board I mentioned a couple
of days ago, I've put a picture at
http://www.ibm1130.org/misc/mits-tty-interface.jpg
The molex connector at the bottom left below the relay
is where the data cable connects. The other end is
a DB25 connector, and the wires go to pins 2-6. Since
there is no connection to pin 7 (signal ground) it must
be current loop.
Brian