Computer Engineering for Babies

[reTrEaD]

[JohnH]

This reminds me of circuits that we rigged up in science lessons at high school, age about 12, out of switches, light-bulbs and a battery.

It taught us computer science AND electrical engineering.

Plus, we learnt either that we wanted to be technical nerds, OR the type who hated such boring details and would grow up to make a lot more $ by employing us.

[reTrEaD]

Jan 31, 2024 7:31:34 GMT -5 JohnH said:

This reminds me of circuits that we rigged up in science lessons at high school

When I was in HS, tubes were still in vogue although transistors were becoming popular and OP amps were the hot new ticket. 7400 series TTL devices were new but we didn't cover those.

It wasn't until I was in tech school that we dealt with logic circuits. We breadboarded circuits like this and also had to synthesize each of these using only 7400 quad two-input nand gates. We could use as many two-input nands as we wanted but extra points were given to those who came up with ways to use the fewest number. Good times, for sure.

I'm wondering if anyone noticed the photosensors in this application?

Jan 31, 2024 7:31:34 GMT -5 JohnH said:

It taught us computer science AND electrical engineering.

Plus, we learnt either that we wanted to be technical nerds, OR the type who hated such boring details and would grow up to make a lot more $ by employing us.

If I could do it all over again, I'd study business primarily and electronics as a secondary course of study. Ooh la la.

[kitwn]

Jan 31, 2024 19:16:29 GMT -5 reTrEaD said:

When I was in HS, tubes were still in vogue although transistors were becoming popular and OP amps were the hot new ticket. 7400 series TTL devices were new but we didn't cover those.

It wasn't until I was in tech school that we dealt with logic circuits. We breadboarded circuits like this and also had to synthesize each of these using only 7400 quad two-input nand gates. We could use as many two-input nands as we wanted but extra points were given to those who came up with ways to use the fewest number. Good times, for sure.
I'm wondering if anyone noticed the photosensors in this application?

Wow, you must be so young! Or perhaps you just went to a more advanced school than I did. Based on the science I was taught you'd think that electricity had only just been invented. Michael Faraday would have been familiar with all the electrical content of my school years.
Fortunately my parents gave me a Philips Electrical Engineers kit for my birthday when I was about 10 or 11 so the whole of my working life rested on one thoughtful gift and what I learned at home rather than seven years at Grammar School.

I didn't notice them at first, but presumably the photosensors are there to tell the circuitry which, if any, page is open to prolong battery life.

EDIT: It's surprising what you miss on the first couple of views. There is only one pair of switches and one LED so the differing number of photosensors uncovered on each page is needed to tell the circuit which logic function to implement.

[JohnH]

hi kitwn

So Im picking up that you are British? and like me, live down in Oz?

I remember those Philips kits, my friend had one. I got by with actual bits of wood as a breadboard, with nails and solder. And then I got a T-Dec plug-in board that you could push components into, and sat upstairs making bizarre and very noisy devices out of transistors and other parts bought as bulk packs. My mother blamed me for any interference picked up on our TV.

I got as far as making a working 8-bit computer in 1977 (SC/MP chip), that you could program in machine code. It had 0.25k of RAM and drove a graphics card with 1k into an old TV. I wrote a shooting game where cruise missiles ('>' symbols) would fly across the screen getting lower and lower, and you fired at them to try to shoot them down with '^' symbols and if you hit one it would explode with a satisfying '*' symbol. The score would increment. But if you kept missing, the missile got lower and lower until it dived down steeply and blew you up with a mushroom cloud of *'s !. At that point development had to be put on hold due to no more RAM.

Then I thought, I'm sick of this, there's never gonna be any future in it, and I went off to study structural engineering. Apparently Bill Gates came to a different conclusion in his garage.

[kitwn]

Feb 2, 2024 19:26:21 GMT -5 JohnH said:

hi kitwn

So Im picking up that you are British? and like me, live down in Oz?

I remember those Philips kits, my friend had one. I got by with actual bits of wood as a breadboard, with nails and solder. And then I got a T-Dec plug-in board that you could push components into, and sat upstairs making bizarre and very noisy devices out of transistors and other parts bought as bulk packs. My mother blamed me for any interference picked up on our TV.

I got as far as making a working 8-bit computer in 1977 (SC/MP chip), that you could program in machine code. It had 0.25k of RAM and drove a graphics card with 1k into an old TV. I wrote a shooting game where cruise missiles ('>' symbols) would fly across the screen getting lower and lower, and you fired at them to try to shoot them down with '^' symbols and if you hit one it would explode with a satisfying '*' symbol. The score would increment. But if you kept missing, the missile got lower and lower until it dived down steeply and blew you up with a mushroom cloud of *'s !. At that point development had to be put on hold due to no more RAM.

Then I thought, I'm sick of this, there's never gonna be any future in it, and I went off to study structural engineering. Apparently Bill Gates came to a different conclusion in his garage.

John,

Right on both counts. My home based electronic ventures weren't nearly so advanced as yours. I managed to build the various circuits in the Philips kit including a SW radio that sparked an interest in radio and later a 100W amplifier for making my attempts at guitar playing even more annoyingly loud that they already were.

after a few listless years after school I got an amateur radio licence ( I managed to wangle the callsign G0 KIT ) and that led me into the BBC as a trainee transmitter engineer. I ended up spending my last 16 years in England teaching other aspiring engineers at the Beeb's engineering training department.

The BBC kindly made me redundant in 2004 and my wife and I came to Australia that year, originally near Perth, WA and then further North in Exmouth. We first went there on holiday and saw what I believe is still the largest wireless antenna in the Southern hemisphere "I know what that is, I could work there" said I, and a couple of years later up we moved.

At the end of 2020 we retired to the more temperate and less isolated climes of Northern Tasmania where my electronic talents include programming Arduino's to do tasks like run a wooden clock and water the veggie garden. I've also built a guitar and have plans to build another one with room for me to play with low-impedance pickups and state variable filters in the style of Helmuth Lemme, Joh Lang and Mr Fishman. That's if I ever get enough time off from mowing and weeding our 2 acres of Tasmania. Everything grows b****y fast down here!