A 1961 Relay Computer Running in the Browser
minivac.greg.technology
A 1961 Relay Computer Running in the Browser
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Re: A 1961 Relay Computer Running in the Browser
#2"Before microchips existed, computers were built with mechanical relays." Should probably say something about vacuum tubes as well!
Re: A 1961 Relay Computer Running in the Browser
#3"Before microchips existed, computers were built with mechanical relays." Should probably say something about vacuum tubes as well!
And discrete transistors. Now that my curiosity is piqued, I found this nice timeline:
https://www.computerhistory.org/timeline/computers/
It looks like transistorized computers were dominant at the point when integrated circuits were introduced.
Re: A 1961 Relay Computer Running in the Browser
#4"Before microchips existed, computers were built with mechanical relays." Should probably say something about vacuum tubes as well!
And discrete transistors. Now that my curiosity is piqued, I found this nice timeline: https://www.computerhistory.org/timeline/computers/ It looks like transistorized computers were dominant at the point when integrated circuits were introduced.
And before that with gears! (With limited success.)
Re: A 1961 Relay Computer Running in the Browser
#5well the fact that you can wire the Rotary Switch to power and the thing physically rotates --- that's definitely Haptic Feedback that i dont ever recall seeing in a computer. lol.
that manual is wild too. entire section on games.
reminds me a lot of those old radioshack "build your own circuit" boards. the wires to components especially but also the manual, the way it just builds up dozens of examples from simple to complex, so if you really wanted to, a child could work their way through it slowly and understand everything.
looks like the inflation adjusted cost would be around 900 bucks today.
Re: A 1961 Relay Computer Running in the Browser
#6I imagine it would be easier for me to build the simulator than to make it do anything of interest.
Re: A 1961 Relay Computer Running in the Browser
#7Earlier quoted context omitted.
And discrete transistors. Now that my curiosity is piqued, I found this nice timeline: https://www.computerhistory.org/timeline/computers/ It looks like transistorized computers were dominant at the point when integrated circuits were introduced.
And before that with gears! (With limited success.)
Indeed, my dad was a research scientist at a large chemical company, and every scientist had a Friden mechanical calculator, which was capable of multiplying and dividing. But it was not a programmable computer.
When the HP 35 came out, it was cheaper than the annual maintenance contract for the Friden. They bought one, and passed it around to try out for a week, then all of the Fridens went into the dumpster. Of course he brought one home, and we got to play with it.
Re: A 1961 Relay Computer Running in the Browser
#8[deleted]
Re: A 1961 Relay Computer Running in the Browser
#9Thank you so much everyone, this is something I've worked on for a few years on and off -- I posted about it here in a Show HN a few hours ago [0]
The biggest unlock was finding Willy McAllister's excellent Circuit Sandbox [1], which provides the Minivac Simulator's underlying electrical math. I tried so many approaches to simulate electricity (a doomed DIY approach, Falstad, Spice...) but Circuit Sandbox's DC analysis did the job perfectly.
Ping me for questions, and would love to read your feedback!
Re: A 1961 Relay Computer Running in the Browser
#10well the fact that you can wire the Rotary Switch to power and the thing physically rotates --- that's definitely Haptic Feedback that i dont ever recall seeing in a computer. lol. that manual is wild too. entire section on games. reminds me a lot of those old radioshack "build your own circuit" boards. the wires to components especially but also the manual, the way it just builds up dozens of examples from simple to…
The Rotary Switch - which is both input and output in the real Minivac - is absolutely wild yeah.
One of the crucial things I didn't get to yet is making that wheel controllable - some circuits in the manuals do require you to turn it. That's high in the todo list (with mobile support).
I also really want to share all of the videos I've been collecting of similar "wheels" - in (modern-ish) elevators [0] and light shows [1]... And also pinball machines! [2]
Re: RadioShack boards, I did have the "300 in 1" kit growing up, so yes... it's full circle for me. :-)
[0] https://www.instagram.com/reel/C3dk5GkJni6/ and https://www.instagram.com/reel/CzuHXKRpuN-/