Restoring 486 pc from the junkyard

Working on another PC from junkyard. Page with Chaintech motherboard support information and bios updates. Motherboard Manufacture: Chaintech 4SPIChipset: SiS 85C496/7BIOS String: 02/16/95-SiS-496-497/A/B-2A4IBC31-B2BIOS Version: Award v4.50G Fixes CPU fan holder was broken, so I have 3d printed mount for a CPU heatsink holder and then hot-glued old fan case to it. Seems to work ok […]

Back to the 90s, adventures in restoring retro PC from the junkyard

Recently I came up with the idea to build myself a newer retro PC from the ’90s, something like the first Pentium with DOS 6.22 and Windows 3.11. I have a couple of retro laptops running Windows 95 and Windows 98. The motivation was that I want to have a retro desktop PC with as […]

Modify Arduino 5v relay module to work from 3.3v

I am implementing a power-off function for my Ender 3 using OctoPi. For that, I need a relay and I happened to have one. Unfortunately, after connection relay to Raspberry Pi GPIO pin, the relay was always on and not listening to any commands from OctoPi. It appears this module was designed for 5v logic […]

Removing supervisor password (SVP) on ThinkPad T42

Recently received two ThinkPad T42 laptops ( some company decided to upgrade its IT and were giving away them almost for free ). After turning them on got an 271 error and later was prompted to enter password. It seems battery was dead on both of those laptops and when its dead, real time clock goes […]

ZX Spectrim 128 +3 composite video output and drive belt replacement

Did some work on ZX Spectrum 128 +3 I have. One thing was I wanted to make it work with small “TFT Color monitor” (for a car rear view). This monitor has a composite video input. First I tried using CSYNK and GND signals for a composite video input. You get the video but it […]

Sony Ericsson that have tx-rx connection

Sony Ericsson that have tx-rx connection: 2218z, A2618s, A2618sc, A2628s, A2628sc, F500, F500i, J200c, J200i, J300a, J300c, J300i, K300a, K300c, K300i, K500c, K500i, K506c, K508i, K600, K608i, K700, K700c, K700i, P800, P802, P900, P908, P910a, P910c, P910i, R300d, R300LX, R300z, R310s, R310sc, R320s, R320sc, R380e, R380sc, R380s, R380WORLD, R520LX, R520m, R520mc, S700c, S700i, S710a, T200, […]

Making an adjustable “lab” power supply from scrap

Had an old power supply board lying around that was ripped from dead/old printer. PSU model is CZ57PSE EPSON To make it work one should connect PSC line to ground. Schematics of similar power supply: To regulate output, made an adjustable voltage regulator using LM2575 that was ripped of some dead router or something similar: Finished […]

ESP12E dev kit “cant autodetect firmware, because proper answer not received.”

After flashing NodeMCU dev kit to latest build could not connect to it with ESPlorer, error was – “cant autodetect firmware because proper answer not received.”. It was because baud rate was changed in later firmware, after setting the baud rate to 115200 all was fixed.

Making old webcam to work on Windows 10

Was investigating some old Fujitsu Siemens Webcam for some project, but it did not work on Windows 10 – windows did not recognize and did not have any drivers for it. Hardware ID in device manager shows: USB\VID_0C45&PID_613B&REV_0101 USB\VID_0C45&PID_613B Searching by vendor and PID did not help. On the PCB of the webcam, I found that […]

Intel i5-8600k 5000k overclocking settings

Mother board MSI PC PRO CPU overclock BIOS settings: Multiplier 50 Voltage fixed to 1.3v RAM overclock BIOS settings: XMP Enabled, profile 2800 Memeory Try it Enabled, Memory Try It Limit selected.