Help with Beta8 aka Alpha1 by MCS Micronic Computer Systeme

[Eversberg]

Hey everyone

I recently bought an Grundig telepilot prozessor, which is indeed an Alpha1 from MCS in a 19" housing. The Alpha1 is an modular KIM1 derivate from a german company, brought out in 1977.
I was very lucky to get my hands on it. I could enter some little programs ans save it to tape.
But yet I was not able to connect it to a terminal: neither the V.24/TTL nor the current loop shows a signal, they're totally dead.
The original handbook is no real help. The description of the hardware is rudimentary and the circuit plans in my copy are hardly to read. I even can't find the position of jumper 7.

Can anyone help me with a good copy of the circuit plans or with some further information about this machine.

I'll thank you for any help
Frank

[ttlworks]

Hi, and welcome to the forum.

Maybe this helps:
http://retro.hansotten.nl/home/6502-sbc/mcs-alpha-1/
http://retro.hansotten.nl/uploads/alpha ... habuch.pdf

When looking at the schematic at page 11 of the PDF, it feels like jumpers S7 and S8 might be on the big PCB,
and somewhere close to the optocouplers... but the handbook doesn't show the location of the jumpers.

From the text on page 23:
Both jumpers S7 and S8 have to be closed for V24.
Both jumpers S7 and S8 have to be open for current loop.
// Factory default setting is V24.

[Eversberg]

Thanks for the hint.
I found the same, but in better scan quality: ftp://ftp.informatik.uni-stuttgart.de/p ... kt1977.pdf

The jumpers S1 to S8 are on the PCB M627 which is on the front plate, staggered together with keyboard/7-segment PCB M626.
It is just a normal IC socket between IC 05 and 565 There is no print or other hints. Only mark on the socket seems to show S1.

By now, i couldn't run my Beta-8 with a Terminal. One of the two optocouplers seems to miss. Now i will try to connect via TTL pins 3 & 9.

Frank

[DL4DBY]

Hi Frank,
first of all: Happy New Year!
I have the MCS-Alpha I and some Dokumentation. Perhaps I can help.
I'm living in Westfalia.
If you want send me a pm please.
All the best
Charly, DL4DBY