When my Engineering Education began I was in Junior High School in
Marion, Indiana. The transistor was celebrating it's 10 yr.
anniversary and they were way too expensive for experimenters like me.
Vacuum Tubes were still king and B+ was a lot more important than Vdd.
As the years have trekked by I have added to that knowledge base with
DC-Relay logic, Fluidics, TTL Ckts., IC's, Main Frames, Micros, and
for 30+ years PC's.
IBM 3560, DEC Mini-Main Frame, Burroughs 910, AS-400,
HP-3000, Micro-controllers from Intel, Motorola, NEC, Toshiba, Zilog,
AMD, COPS, Siemens and so many others that I don't even remember their
#1 My first one was a deck of 3X5 cards with holes punched for
Binary and slits for sorting, adding etc. using a long wire probe.
#2 Was a DC relay driven state machine with a Drum Type Memory.
Controlled a robot. It was about 50% built from scratch and 50%
taken from a junked machine controller. All the logic was done with
24v. DC and a small motor that would stop at at any of 48 notches on
the drum. The motor ran from 12v DC and was in series with taillight
bulb from a car. I ran it with four 6v car batteries. At a
preselected positions various micro switches would engage and control
the robot functions. I used a hard wired cable to connect a
"control" box to the "logic". The display was a
clock hand at the end of the drum pointing to a number on a face
plate. Each relay had a small 24v pilot lamp that indicated its
#3 Was a giant sorter and printer that prepared envelopes with
addresses. It also was a state machine with paper tape for memory.
Had TTL and vacuum tube Flip-Flops. Display was 256 #47 pilot
lamps! It was from the dumpster at the Sun Chemical Building in Ft.
Lee, NJ. I had to leave it when I moved to California (but kept the
paper tape reader /writer). I never
figured out how to change its hard wired program. It must now occupy
10 cubic feet of landfill.
#4 Was a 4-bit NEC CNC machine controller. Had IC's, TTL Logic,
Diode Matrix Programming, A 2k state machine ROM. and 16 bytes of
TTL ram each byte was on an individual card. I kept the paper tape
reader from #3 above and used it to both program and supply data.
The tapes could be spliced together to use the program part over and
just add new data. I tried valiantly to get the output to go to a
video monitor but was never able to get all the IC's I needed to
build the electronics.
#5 Was an EXON word processor (Z-80 processor). Unique in every way.
#6 A home built XT clone (8080 processor). Two Floppies 64k, & way too
#7 Used AT-clone. (286 processor) First Hard Drive (10MEG). Color Monitor
#8-#??? a whole array of 386, 486, Pentium and god only knows
what else was under the cover now, PCs. Mostly used -- Some very well used!
All were used to design and test Keyboard Interfaces while self
#30 +/- HP Pavilion XT914 800mhz, 128 mb. ram, 30 gig
hard drive, and a CD-writer that died after a couple of years. This
Computer died a terrible death. It's primary data bus became intermittent
and the Hard Drive sounded like a freight train. It had to be
scrapped, but served me well for 5 years. It was turned on for 8-16
hours a day during that time.
#31++ 9-23-04 HP Pavilion Model
3gig AMD Athlon processor, 512 Meg. Mem., 80 Gig Hard Drive, CD-RW.
So why another HP -- I have to say I have had very good luck with
them. There are things I don't like about HP but the advantages outweighs
the problems. I have worked on many brands and they are one of the
best for the price. This computer cost almost exactly the same as my
first IBM XT-Clone!