4 ms·
And the reason for a circular design is so that the wire lengths could all be under 4 feet in order to achieve actual projected clock rates. I saw the thing in
by datameta 2y ago
And the reason for a circular design is so that the wire lengths could all be under 4 feet in order to achieve actual projected clock rates.
I saw the thing in the Computer History Museum in Mountain View. Highly highly recommend the museum to every HN user. I went through it twice, first with the greybeard volunteer guide, and then looped in by myself straightaway.
- Y_Y 2y agoTo offer a second opinion, the Cray-1 was the only thing I found cool about the Computer History Museum in Mountain View. It was otherwise just a like a big website, the history was all dead. In contrast the National Museum of Computing next to Bletchley Had lots of computers turned on, with enthusiast volunteers demonstrating and explaining things. You could punch paper tape and feed it to the Dekatron and see the memory changing as the program ran, or poke at magnetic core memory sheets and someone was right there to discuss all the old tech.
- creer 2y agoI do miss the old "visible storage" Computer History Museum - where you could walk around and peek into so many great machines. The current version has been musee-ified to death. It might safer from flocks of school kids but a real shame for the rest of us.
- rbanffy 2y agoThey have very strict policies around powering up their devices. I tried to persuade them to look into the original IBM 2260 terminal font design (it is implemented as core memory with missing cores for bits and it resided in the terminal controller). Of course they said no.
- datameta 2y agoMy mind was absolutely blown by mercury delay line memory of the UNIVAC 1. The things we did before silicon dynamic memory were works of crazy engineering. https://en.wikipedia.org/wiki/Delay-line_memory https://en.wikipedia.org/wiki/Delay-line_memory
- Y_Y 2y agoI felt the same. It never even occurred to me that you could you use a physical compression wave in a fluid as memory in a real computer. Here's a delightful snippet from that article btw: > Alan Turing proposed the use of gin as an ultrasonic delay medium, claiming that it had the necessary acoustic properties.
- rbanffy 2y agoWe should build a computer that uses lasers and the Apollo retro-reflectors as delay-line memory. It’ll be the largest computer in the solar system. Who’s in?
- akira2501 2y agoMy favorite are the "glass delay line memory." https://archive.org/details/TNM_Glass_computer_memories_-_Corning_Electronics_20171206_0185/page/n1/mode/2up https://archive.org/details/TNM_Glass_computer_memories_-_Co...
- ForOldHack 2y agoIs this a Williams tube or a Mellon tube? I have seen ONE or these, and they used to be more numerous than pocket change, at least the ones that no longer worked. Unused they were treated like fine crystal, used like empty beer bottles. I wanted to hook one up in a tv to see a 1" movie, or maybe a 3/4" movie with the aspect ratio but the refresh rate was really slow, so it was useful as a memory.
- ForOldHack 2y agoThe CHM is cool, but my cousins went to Bletchley, and were very impressed.
- Rebelgecko 2y agoYou might also like the National Cryptologic Museum next to NSA's HQ. The Cray they have isn't as interactive, although you can sit on it for the Sneakers vibes. They have multiple Enigma machines you can play with which I thought was pretty fun
- ForOldHack 2y agoVery highly recommended. The Cray was very cool. Had to explain why there was a wire 11.8" long framed. ( Thank you Rt Gen Grace Hopper! ) I walked through twice without a greybeard, and then when I went with a guide... I started smirking when ever he made a mistake... He finally started asking 'Do you have anything to add?' and I only make a few small corrections, until we saw the wire. 11.8". I would think that the Cray would be designed to keep the wires under 3' 11.21" ( 4 nano seconds ) There are PICTURES! https://www.flickr.com/photos/carrierdetect/3599257794/in/photostream/ https://www.flickr.com/photos/carrierdetect/3599257794/in/ph...