Messina Electronics - Johannesburg, South Africa
[1982 - 1984]
In early 1980s,
a micro-computer, based on the eight bit
operated at either 1MHz or 2 Mhz clock.
The so called "Commander" micro-computer, was programmed with a Basic-like
Process Control Language (PCL)
developed in-house using
. PCL featured very specialised Real-Time functionality, targeted at
for industrial applications. The Commander peripherals included 10MB
Pertec Cartridge Disk Drives, 8" flexible diskettes and a cassette tape.
The "Commander" conquered the South African market, competing against the
(later giant) AppleII and was installed in industrial
"Turnkey Process Control"
at Mines, Breweries, Sugar Mills, Soap manufacturing factories,
Truck engines production and in office type applications, like
Accounting and Inventory Control.
Messina Electronics also manufactured
"water level detectors"
for the South African military industry.
The innovative design of these units involved the manufacture of a
hybrid circuit and some high quality encapsulation technique, within
military standard enclosures. The units were installed in army vehicles,
but after some exhaustive tests and a short field run, a significant
percentage of the units malfunctioned.
My investigations concluded that test carried out by the Quality
Control department, was responsible for the hybrids "hardware
weekness". The test-rig that was used, produced inversed voltage
(inductive) spikes, as various loads were switched in and out for
routine quality test measurements. These spikes caused just
enough fatigue-type damage, clearly visible under the microscope,
that weakened the units to the extent that shortly thereafter
they would fail. I had suggested to connect a Germanium diode (with
a low cutoff voltage, of under 0.3V) in parallel to the switch
contacts. Our Production Manager Mr Hank Grootveld, the Engineering
Manager Mr Norman Brown and our Managing Director Mr. Pat O'Sullivan
were very happy indeed when the production line was reinstated.
1982 - 1984