Repair Reference

The deltas that matter on the Japanese and PAL siblings of the NES: the DC power-polarity trap that kills a Famicom, cleaning the 60-pin connector, replacing and re-aligning a Famicom Disk System drive belt, expansion audio, and RGB/HDMI mods. Companion to my NES front-loader reference.

How I diagnose and fix the original front-loading NES (NES-001): the blinking light, the 72-pin connector, no-power faults, video noise, plus what the hardware is doing inside and the mods worth knowing.

How I work on the standalone Sega Genesis and Mega Drive: the DC polarity flip that runs opposite between Model 1 and Model 2 and will reverse-feed a board, telling the VA0 through VA7 and Model 2 revisions apart and why the board decides audio quality and mod compatibility, the VA6 reset-cap trap, a frequency-ordered fault guide, and which mods are cable versus board surgery.

How I diagnose and fix the whole Game Boy line, from the DMG-01 to the Advance SP: the centre-negative power trap that kills a DMG, the vertical-line LCD reflow, which board revision you actually have and why it decides every screen and recap job, and the caveats that separate a good buy from a parts donor.

What I have pulled together on the NEC TurboExpress and its Japanese twin the PC Engine GT: the centre-positive power trap that shares a barrel with the Game Boy DMG, the 18-capacitor recap that the community treats as mandatory on every single unit, the one 4.7 uF cap behind the backlight-on-but-no-picture fault, and the connector pinouts worth metering.

How I diagnose and fix the Sega Game Gear: dead and dim screens, no sound, the recap that every unit needs, the power-jack polarity trap that tracks region rather than NTSC/PAL, and how to tell the board revisions apart before you buy a screen kit.

How I diagnose and fix the Super Nintendo and Super Famicom: why the board revision decides everything, the dead-power and no-picture faults, the bright vertical line, audio imbalance, the 1CHIP quirks that are not faults, plus region conversion and the RGB mods worth knowing.

My companion page to the Genesis reference, covering the two add-ons that bolt onto it: the polarity split that puts both Sega CD models on a centre-negative supply while the 32X takes the opposite one, the three-stage boot ladder that localises a dead Sega CD in thirty seconds, the Model 1 capacitor and tray-mechanism jobs, the Model 2 fuse, and why the 32X's famous video noise is a switching regulator rather than a fault.

How I diagnose and fix the top-loading New-Style NES (NES-101): why a bad cartridge gives a black screen instead of a blinking light, what the jailbars really are, the soft-failing 7805, the one capacitor that matters, and the AV mod that turns an RF-only console into a sellable one.

How I work through a Nintendo 64: why the board revision silkscreened on the mainboard decides the whole video-mod story, why a red LED with no picture is usually a Jumper Pak rather than a dead board, why a dead N64 is nearly always a dead power brick, and what the documentation on this machine does and does not actually cover.

How I work a GameCube from the documentation: why the Digital AV Out port decides everything about what a unit is worth, the disc-read-error stack that accounts for most failures, the +12 V pin that kills consoles during an HDMI mod, and what actually differs between a DOL-001 and a DOL-101.

How I diagnose and fix the Wii family: telling the original, Family Edition, and Wii mini apart, why the optical drive is the console's real weak point, power and video-output troubleshooting, and which caps and connectors actually matter.

What the RetroN clones actually are before you buy or fix one: which models play real cartridges on clone silicon and which dump the cart and emulate it, the RetroN 5 wrong-adapter death that kills a $6 power chip, why flash carts and homebrew fail on the 5 by design, the SD-card-is-everything RetroN 77 and Sq, and the NOAC audio defect on the 1/2/3 that is not a repair.

How I work the 3DS family from the documentation: why this is the one console in my reference set where the answer to "should I recap it?" is no, why the model name on the box is a bad guide to which battery, screen or reader you need to order, the six-model board map, and the fault list that is almost entirely mechanical.

Every console of the 8- and 16-bit era had to get a dozen button states down a thin cable, and each one solved it differently: an off-the-shelf CD4021 in the NES pad, Nintendo house shift registers in the SNES pad, a 74HC157 multiplexer and no shift register at all in a Genesis pad, and a full microcontroller speaking a serial protocol by the N64. That choice, made for cost reasons thirty years ago, is what decides today whether a dead pad is a part you order or a donor you hunt.

I opened five flash cartridges, from a ten-dollar AliExpress bootleg to an SD2SNES, and photographed what sits between the edge connector and the chips. What separates them is not what the marketing says: it is series resistors, transceivers and decoupling, in that order. Covers whether a cheap cart can really damage your console (the cartridge is what dies, and the scarier claims do not survive checking), which consoles the issue even applies to, why a black screen and reset loop is harmless lockout, how to identify a risky board, and a correction to my own long-told story about SNES video noise once I finally opened the carts involved.

Why the Sega Game Gear and the Genesis / Mega Drive share a repair DNA: the same Z80 CPU, the same SN76489 sound generator, and a Master System-family video processor sit inside both. What that shared 8-bit core means for skill transfer on the bench, where the game libraries actually overlap (and where they only look like they do), and which failure modes belong to just one of the two.