31–39 of 39 posts
Very impressive! At the last Vintage Computer Fest West before covid I saw this on display [1] and was completely taken with the clicky sound and blinkenlights. It does use semiconductors for the memory and IO. I built one last March and April, and found it to be surprisingly enjoyable and relaxing. Highly recommended for those who love clicking and blinking things. [1] http://relaysbc.sourceforge.net/
Earlier quoted context omitted.
Yes, you could. But there are also specialized electronics that work at 450C (or even 500C). NASA Glenn Research Center has developed them. Transistors and such using Silicon Carbide (instead of regular silicon). A simple computer could as easily be made with such transistors and passive elements. It’d be much faster and lighter than a relay computer. The issue with all such computers is developing significant storag…
Ozark Integrated Circuits got a contract from NASA to develop a high temperature RISC-V chip. > Ozark IC will create the first 500-degree Celsius RISC-V multi-chip system in a package as a way to illustrate the techniques, design procedures and the multi-chip package with high-temperature components that go into creating a high-temperature electronic system. press release https://talkbusiness.net/2020/05/nasa-to-give…
Relays were invented in the 1830s. Why were tubes used instead of relays? Do they switch faster?
1958 FACOM 128B Japanese Relay Computer
Sounds really cool when it's running!
If you like relay computes, you might also like this: https://www.youtube.com/watch?v=_j544ELauus 1958 FACOM 128B Japanese Relay Computer Sounds really cool when it's running!
Earlier quoted context omitted.
50Hz basically means the arc is extinguished after at most 20 milliseconds, limiting how much the contacts heat up. For DC on the other hand there's no guarantee the arc will extinguish at all. You can imagine how a sustained arc would be bad for a relay. Of course a higher frequency would heat the contacts even less, and I imagine you could get a relay rated for even higher voltages given a higher AC frequency.
But arcs only happen when the contacts are almost-but-not-entirely closed, I suppose (ionization could be a factor). This time-period is, I suppose, very short, much shorter than the 10 milliseconds of the AC half-wave. I suspect the arc could cause the contact to stick for a while, which may increase the arc time.