PDP11

31
reputation
2

Late 1960s, 5 year, Radio Technician Apprenticeship with the Department of Civil Aviation when 15 years old after completing 4 years of High School. Training was based on vacuum tube (valve) technology and included RADAR systems. Curriculum included astable and bistable circuits, digital logic (e.g. Karnaugh maps), transistors and integrated circuits (RTL, DTL, TTL and ECL). Training would have enabled me to maintain first generation computer systems. The oldest computer hardware maintained was a second generation Burroughs B5500 system.

In the Department of Civil Aviation/Transport I was a Radio Technician, Draughtsman then Technical Instructor. In the Australian Broadcasting Commission the position was a Broadcast Technical Officer/Broadcast Engineering Officer primarily maintaining studio equipment for Radio Australia.

Up to this point I had experience on a number of microprocessors (6502, 6800, 8080, 8085, and SC/MP), completed short courses on BASIC, COBOL, FORTRAN and Pascal. Could write in various assemblers. Had a personal account at CDC with access to KRONOS (became NOS) and SCOPE systems as a teaching exercise (this was before home computers) and for various personal projects e.g. to maintain a radio station's mailing list.

Designed and built

  • Z80 training aid with annotated code (must confess I deliberately included one instance of self modifying code for the Computer Science students)
  • Interfaced a five level (Baudot code) paper tape punch to a Z80 based C/PM system so that a legal firm could eliminate errors from Telex transmissions. For some strange reason (I don't remember why) I was asked to repeat the exercise with an Apple II systems.
  • Modified C/PM operating systems for various devices and configurations
  • To enable customer to run C/PM (Soft sector) and Microsoft Basic (Hard-sector) systems, built an interface to reconfigure an 8 inch floppy disk drive between hard sector and soft sector disk formats. One disk drive interface used Open Collector while the other was Tri-State logic.

Monash University as a Computer Systems Officer maintaining micro, mini and mainframe computer system down to chip level. Monash Computer Centre was unusual in that University staff performed hardware maintenance down to component level for all computers (e.g. PDP-11 and VAX systems, Burroughs B6700 plus their peripherals).

The personal computer revolution had taken off with Commodore, Tandy, Apple, etc. My Personal Computers were a Motorola 6800 system, DEC PDP-11/10 running CAPS-11,, PDP-11/34A running RSX-11M, and VAX-11/750 running VMS.

Education Department as a Technical Teacher. Followed by Tradesman on the production line of small PABX systems.

Telecom Australia as a Technical Officer (Materials Quality Assurance inspector), Senior Technical Officer (Defective Material Reports), then Building Management Systems, LAN Administrator, Network Manager, Systems Documentation, Problem Manager then retirement.