RED = POSITIVE, BLACK = COMMON

It's simple... Everything electronic as far back as I can remember (and I've been taking apart electronics since I was 6) has had this scheme. RED is connected to the positive terminal, and BLACK is connected to the common (usually "GROUND", "COMMON", or "RETURN") terminal. We're talking 5V systems, we're talking PCs, we're talking remote control cars, TV remotes, VCRs, CD players... When you enter college for EE you're provided two wires with clips for your power supplies... a black one and a red one. The labels on the power supplies are Red and Black. Guess which terminals they are... For your signal generators you've got a red connector which is the signal and a black wire which is the ground... It may not be rocket-science, it may not even make 100% sense, but it's pretty simple and it's damn-near universal.

So why is it that two devices I've worked on in the past few days have EVADED this scheme?!

Example 1: PowerBook G4: has a connector with three wires; Red, Black, White running to the hall-effect switch used for putting the system in standby. As I recall (I've since closed it, and have no intention of opening it again) RED was the signal back from the hall-effect. WHITE was GROUND, and BLACK was +3.3V.

Example 2: USB mouse. My stupid mouse, the cheapest you can buy, has a break in the cord near the connector... had to cut it apart to resolder... Wait, something's wrong... what's this red wire doing on GND and this yellow wire doing on 5V?! I musta twisted something when I cut the cables... I checked my logic numerous times... opened up the mouse itself... sure enough, the PCB's labelled with the USB connections, and sure enough they're wired in that weird scheme. (Gray and Black are apparently the USB data signals).

I'm just saying...

Example 1A is a little less exemplary: multiple iBooks: have a four-wire connector leading to the LCD backlight inverter. It's handy to have a 1+kV voltage source around... if not to light up LCD backlights, then just to give yourself a good zap every once in a while. (Seriously, it's a health-thing... kinda like accupuncture). Not *certain* they didn't use the regular scheme, but after Example 1, I'm no longer convinced the reason it wouldn't light-up when connected to 5V or 12V was due to one of the other wires being an "enable." (I still have 'em sitting around for later electropuncture experiments, maybe I'll look at the circuitry next time).

Anyways, it's just stupid. Plain and simple. I have a hard time believing it's not intentional... some Chinese kid is laughing his ass off right now because a repair job on a mouse that wasn't even worth the five minutes it woulda taken to repair turned into twenty minutes... Forty, if you count the ranting here. Meh, I guess it's kinda fun to be frustrated sometimes over stupid stuff with no real victims. (Sorry chinese kids).

(And, if you want some other ranting, this German freak I worked for for way too long insisted that Europeans use Blue for positive and Green for ground, and insisted I follow the same scheme, like I never worked with electronics before I worked for him... goddamned German freak... I love him like an uncle, but I'm still not on speaking terms with him... certainly it's because of the Blue/Green thing. And another thing, Blue and Green?! Seriously!? What about people who're colorblind?! What about low-lighting conditions? I'm pretty sure he just made that shit up so he could use two wires next to each other on rainbow ribbon-cables.)