A very slow un-TRIMmed SSD

Yesterday I was working on my Manjaro Linux laptop when everything slowed to a crawl. I determined the cause to be extremely slow disk write speeds (slow as in maxed out at 2MB/s with the activity light solid on). The drive is a half-full 1TB SATA SSD (T-Force Vulcan Z) that is less than a year old, so I wasn’t expecting it to fail, but I checked the SMART diagnostics anyway.
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What is this Burroughs IPT-7050?

This awesome piece of hardware was claimed to be a punched paper tape reader controller from 1962. I, with no hesitation, picked it up. Opening it up confirmed that it was indeed awesome, although the chip date codes put the manufacture date closer to 1970. The right-hand side is taken up by a gigantic transformer and smoothing capacitor. The left-hand side is a group of five logic boards, with a sixth routing the signals from the front panel and connectors to the backplane.
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Could 74xx logic run Linux?

Why not? I’ve already built something that could be considered a computer. It can’t run native code besides what is on its ROM, so it can’t run a conventional operating system, but it seems like its flaws could be easily rectified. Maybe a bigger 32-bit processor with more registers and a bigger address width could run an operating system. It could, kind of, but a real computer has a more features that are necessary to run an operating system.
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A Radio Clock

Design files and code I found this King KI 266 DME Indicator, part of a 1970s DME radio navigation system that would have been mounted in an airplane cockpit. I only have the display part, so unfortunately I won’t be able to use it to navigate, but it does have two awesome gas-discharge seven-segment Panaplex displays. These types of displays operate similar to Nixie tubes (high voltage makes the neon glow), but each cathode is a segment instead of an entire number.
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Discrete NMOS logic

Series: VMP: A Very Mediocre Processor

Choices, choices… There are lots of ways to do digital logic. I choice NMOS because I wanted to. For the N-channel MOSFETs, I chose 2N7002 in SOT-23 because it was the cheapest. I ended up with 9.1k pullup resistors and 12V supply because it was convenient and seemed to be a reasonable speed compromise (a few hundred ns switching time / 16mW static power). Parts are $0.032/inverter at quanity and cover about 20mm² of board area in 0805/SOT-23.
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VMP: A Very Mediocre Processor

Series: VMP: A Very Mediocre Processor

Git repository Overview VMP is a processor. A very mediocre one. It’s an 8/16-bit Harvard architecture RISC CPU built with 1565 discrete transistors. It can runs at about 30,000 instructions/second, consuming approximately 8W (similar to my entire laptop idling at a few gigahertz). The actual VMP CPU is the stack of boards in the middle of the photo. To the left is a standard IDE hard drive from an old desktop.
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