Interak Computer Restoration

Description

On my journey to 'build an Interak' (https://hackaday.io/project/191234-building-an-interak) I came into the possession of an original Interak computer. One that was constructed, back in the 1980s, by the vendor Greenbank Electronics themselves. This project will capture my restoration of that original Interak computer.

My 'new' Interak was originally built for British Telecom, and intended to form the basis of a swipe-card entry control system. It has a large number of serial ports on the rear to allow for the connection of card readers. It was installed for a time in South Yorkshire, but was ultimately replaced by a mainstream commercial solution, and the now surplus-to-requirements Interak computers were returned to Greenbank Electronics.

This computer has probably spent the last quarter of a century residing in a disused and dilapidated building, so may need a bit of work to get it functional again!

Project Logs

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It lives!
Will • 03/01/2024 at 16:24 • 0 comments

As I randomly slid cards in and out, trying various combinations, I suddenly noticed something. The random characters on screen didn't look so random!

More in-and-out card-swapping, trying them in different slots, and power-cycles... hey, those aren't random characters any more!

A good clean of all the card edge contacts, more card swapping, and hey, it lives!

Ok, so I can't have the CPU in the left hand slot (where it was installed when I received it!) but if I move it to the right then the system at least tries to boot!

So what next? I have an FDC card, and I even have some old floppy drives knocking around (not Interak drives, but standard floppy drives). Even if I can read a floppy though, how would I write a boot floppy in the first place? Hmmm!

TBC.../
What have I got?
Will • 03/01/2024 at 12:16 • 0 comments

The first step, after wiping-off the accumulated grime and surface corrosion, was to assess what I have.

Within the very large - and very heavy! - case were four cards - an MZB-3 CPU card, a VDU-2K (composite video only) 'graphics' card, an FDC-1 Floppy Disk controller (no disks though, sadly) and a QS-1 Quad Serial card. The Dynamic RAM card has either been removed, or this system never had one and just used the spare RAM on the VDU-2K board.

The rear panel has a number of serial connectors, originally for the swipe-card readers to connect to.

Behind that is the power supply, very professionally installed and using the proper Interak power-distribution board.

Once wiped of dirt, the inside looked relatively clean too, though sadly the backplane is not fully populated with edge connectors.

So, does it work? Erm, no! An initial check with no cards installed showed the power supplies to be fine, but installing a minimum set of cards displayed just a screen of random characters. It appears the system doesn't boot. Unsurprising really!