gregsadetsky 7 hours ago

Thank 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!

[0] https://news.ycombinator.com/item?id=45945762

[1] https://spinningnumbers.org/a/circuit-sandbox.html

suckow an hour ago

It's almost hard to believe this is possible now in a modern web browser. It's a really sublime thing and I'm glad someone figured out a way to do this. I remember Web 1.0 before the days of JavaScript and P.H.P. allowed interactive websites... Indeed, it's entirely different now.

zkmon 7 hours ago

When you attach a name as inventor of something, it sounds as if the whole concept was borne by them, which is not true. All "inventors" and "great leaders" are only carriers of incremental change, which sometimes marks a milestone for a series of changes done by their predecessors or the context.

Steam engine concepts were already there before Jame Watt, logic by electrical circuits was already there before Shannon. People provide incremental guidance for the change, like river banks do to the flow of the river. No single part of the river brought the river upto that point.

  • adrian_b 2 hours ago

    There are many cases when the incremental change that is due to an individual inventor is very clearly defined, so it is known precisely which is the contribution beyond what was inherited from the predecessors.

    For that incremental change, the name of its inventor is appropriate.

    However, you are right that too frequently people fail to distinguish what was new and what was old in an invention, and they misleadingly attach the name of the inventor/discoverer to the entire big system or theory, not to the small features that are truly new.

    The inventors or discoverers are frequently guilty of this themselves, by failing to properly acknowledge their sources and by making exaggerated patent claims, which nowadays are too frequently accepted by patent offices that do not perform an adequate search of prior art.

etaioinshrdlu 9 hours ago

"Before microchips existed, computers were built with mechanical relays." Should probably say something about vacuum tubes as well!

  • analog31 9 hours ago

    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.

    • hbrav 8 hours ago

      And before that with gears! (With limited success.)

      • analog31 7 hours ago

        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.

    • aebtebeten 3 hours ago

      I like how the 1937 "Model K" adder is literally on a breadboard.

      (are those knife switches in the upper right?)

don-bright 8 hours ago

well 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.

anonzzzies 2 hours ago

Ah yes, I have a stack of these; lovely things for kids to learn some basic stuff. They are the oldest systems I own and they still work (they are fairly easy to fix).

CamperBob2 7 hours ago

Do NOT overlook the manual .PDFs. They are crazy awesome. These people cared about what they were doing.