i have found the jankiest phone system ever constructed. just take this in for a minute, absorb its extremely dark energy ImageImage
had to reverse engineer this shitshow with some friends but i got it sussed out now. those aren't network cards on the right, they're T1/PRI, and the ones with huge connectors are 24-port analog phone line cards
here's the inside. bottom card is a single board Pentium 4, but it's all going into a 14+ slot *ISA* (!) backplane feeding this bank of Dialogic phone cards. Image
the cables hanging out below the RJ-21 ports on the back are external power input - each card requires one of these big fuckoff power bricks because there's no way an ISA slot can power four of these beasts ImageImage
the ribbon bus between the cards is particularly delightful - it's SCBus, a *TDM* interlink for telephony Image
speculating: when a call comes in on e.g. a T1 digital channel, the CPU makes the decision to terminate it to e.g. analog port 4, and then just tells the T1 card "send it to TDM channel 4, card ID 7" - those little dials next to the ribbon connectors set the card IDs
because this system is handling at least 96 lines (probably phone stations) there's absolutely no way the CPU *or* the ISA bus could handle all that data, so the cards just have their own private backchannel for it. beautiful
so it all makes sense but if you just look at it, it feels like it must have spent more time broken than working in its lifetime

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More from @gravislizard

25 Nov 20
here's an opinion i've had about retrocomputing / nerd culture for a long long time
the overwhelming majority of "cool" computers that everyone "wishes they had" were created to perform dreadfully boring tasks, by people who wished they were anywhere else, in the service of people who did a ton of coke and left our economy a smoking husk that can't support life
you do not want a cray-1. all they are is calc.exe but very fast and you can't even touch the buttons, you have to write a program that touches them. the purpose of a 'supercomputer' is to sit humming for 24 days and then produce a single integer, or 25 million integers
Read 23 tweets
24 Nov 20
unboxing a protogen. lifting them out of the styrofoam blocks. peeling the plastic film off their faceplate
throwing away the 6" USB cord that came in the box and digging a nice 10' anker with a velcro strap out of a drawer, plugging it into their ear. CHARGE COMPLETE IN: 116 HOURS. you dejectedly sit on the edge of the bed and look at your phone
series of snapchat screenshots
"unboxing my protogen"
"man they used those packing peanuts ugh haha"
"nice long cord"
"here's his d*ck"
Read 4 tweets
20 Oct 20
imagine if microsoft offered professional services to anyone who could pay. i would pay $300, one time, to have someone at MS who actually knows something log into my PC and figure out why explorer can't render thumbnails
no sfc /scannow bullshit, i mean they raymond chen that shit, they get in and coredump explorer and go "okay you have a png library that paint.net installed, that's the problem"
honestly, i'd pay any company for that if they were trustworthy, but "repair windows pc" is basically a stopword. there are hundreds of millions of people who think they have complicated and interesting problems, but don't, and millions of amoral vultures preying on them
Read 21 tweets
18 Oct 20
i'm watching the first episode of house m.d. out of curiosity but almost the entire episode is in monochrome other than flesh tones and i swear to god the house m.d. i watched on hulu in 2007 didn't look like this. i love the revisionist history of rereleases
this is absolutely not how it looked when i watched it 15 years ago. what the fuck is this war crime color grading it looks like i died in a 1950s hospital and my ghost still haunts that place @Emoji_Nakamoto ImageImageImageImage
the last movies i watched were 300 and sin city and they had more life and saturation in them than this. this is *not* what i watched in 2008.
Read 18 tweets
27 Sep 20
occasionally i try to play a diablolike - i apparently bought grim dawn ages ago? i have no memory of this. but like. do you like this game? i have a question: when you look at this, do you... see something? not just a blur?
i don't understand how a human brain can contain this many numbers simultaneously unless you're a math savant. this is what every single diablo game (including current-patch diablo ii) looks like now and I just don't get it.
i don't understand what's fun about having 9 things side by side that have literally 20+ attributes i need to compare, all of which differ by a percent or two, and no shorthand whatsoever for deciding which i should use
Read 22 tweets
26 Sep 20
power outage selfie
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Read 4 tweets

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