⚠️Danger: Electrical Shock Risk ⚡️
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Mac Mini G4 Restore
I needed to use a SCSI film scanner with software that ran on PowerPC, so I set up an older Mac that supports PowerPC. I decided on the Mac Mini G4 due to its compact size and built-in DVD player. Yellowing: Restoring the original color The original Mac Mini G4 units often show heavy signs…
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Connect Super Nintendo to a Commodore 1084-D
I wanted to connect my SNES to my NTSC Commodore monitor using RGB, so I decided to make an adapter. The 1084-D supports four different video inputs: Analog RBG will give the best picture for an SNES. Initially, I ordered an SNES SCART cable, took it apart, and just planned to connect the RGB and…
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TRSDOS v2.3 for Japanese TRS-80 Model 1
Introductions The TRS-80 Model 1 was introduced to Japan in 1979, with a custom keyboard and Kana support. The keyboard PCB and ROMs were completely different. In order to support the Japanese Kana characters, multiple changes were made to the ROM, resulting in a larger ROM size and an extra ROM chip on board. One…
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TRS-80 XRX-III Mod
Introductions The XRX-III mod is a synchronous 500-baud wave shaper for the TRS-80 Model 1 computer. It greatly improved the reliability of reading data from a cassette tape. Note that this MOD is unnecessary on the latest ROM v1.3 as a fix was put in the software. Additionally, any mods for 750-baud and 1000-baud mods…
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Apple II A2M001 Power Supply
Intro I have 2 Apple II power supplies which need some restoring. One had several parts picked from it, and the second was sold as-is. Although the two power supplies have different-sized PCBs with different layouts, the components on the two are exactly the same. The shorter board is from December 1978. It’s labeled as…
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Ultenic H8 Humidifier EF Error Fix
Background I got the Ultenic H8 humidifier last winter on Amazon. A couple month later it displayed the “EF” error on boot. According to the user manual, “EF” error means that there is too much water in the basin. Emptying and refilling the humidifier fixed the issue. We put the unit away for the summer…
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TRS-80 Model 1 Replacement Power Supply
The objective here is to make a low-cost replacement power supply. We’d like to stay close to the original design. Picking the Transformer Below is the schematic for the original power supply. More info on the original can be found in this article. We’ll need a transformer with two center-tapped coils on the secondary side.…
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TRS-80 Model 1 Power Supply
Background I recently got my hands on a TRS-80 Model 1, but it didn’t come with a power supply. I figured not a big deal, I should be able to build one. However the more I looked in to the power supply and the available replacements, the more bewildered I got about this mysterious power…
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Commodore CMD 2040/3040 Drive Spin-up on Power Down
Background I recently finished restoring two non-working Commodore CMB 3040 Machines. After a while, I finally got them both in working state and able to read disks, but one of the drives still had one small oddity. When I turned the main power switch off, the disk drive would slightly spin up for a couple…
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Hello World!
Welcome to my website, Shock Risk. The site contains any projects I’ve been working on or would like to share which I find interesting.
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