ABI Electronics
(Digital In-Circuit IC-Tester)

(Circa 1986)

last updated May 1, 2010


I threw this page together after selling a good old workhorse, the ABI in-circuit IC tester.

I aquired its bigger brother the BoardMaster 4000, so sadly its days were
numbered on my test bench. Before I sold it, i thought i'd tear it down and
take photos of it just for reference...

Here it is with its top panel removed
The PSU is on the left, the mini CRT is a self contained frame on the right.
This is the underside of the keypad. When i first got this unit, it used to act like it had a bad debounce, it would count multiple inputs for one press. It was very annoying, and then some buttons just wouldn't work sometimes. The tracks are hair-thin and when i metered them out, even though they look fine, and they're not exposed to any knocks or scrapes, some were in fact open so i had to patch a wire or two in to sort that out.
Front keypad frame removed.
closer look...

The rear of the unit, there is a printer port interface (Centronics?) plus the RS-232 serial port whcih i never tested.

ABI Electronics LTD. Serial number : 128613

Here is a better look at the motherboard itself, you can see it uses several 8255's, and the heart of the machine is a Z80. It uses a MC6847 CRTC for graphics i think.

The EPROMS are labelled
IC5 - Intel 27256 - labelled "110 (1)"
IC6 - TMS 27128 - labelled "DIT / 110 (2)"

CLICK HERE for the EPROM code dumps.

A shot of the CRT type number.
Side view of the CRT, its a funky little green screen.
The interface to the DIT is by way of al ittle edge connector through which signal and power travels.
LOPT and other labels..
The power supply is supposed to supply the UUT as well as the tester itself,
it is marked ISS VMS 2450.
when you first power it on, after the crt has warmed up you see this
This is what you get when you run the 'SELF-TEST' function.
Here is a typical screen showing the tester having just run a test of a 74161 when it wasn't plugged into anything.


Its a good GO/NO-GO sort of tester, but it does have its limitations.
It is an amazing time saver, but once you get the 4000 you realise where it lacks power.


Hope its useful to someone, someday, sometime in the future....




Comments? Suggestions? Insults? Death threats? Go on, e-mail them to me.

These pages are (C) Andy Welburn 1996-2010. I cannot be held responsible if the information supplied herein results in a blown monitor/power supply/house fuse/mind. Oh yeah, have a nice day :)