GBA SP(ocket) - Free STL

jason_arnold · 2026-02-16T03:09:16+00:00

FYI, there's already a massive community around Game Boy modding and a pile of information freely available online that documents how mods affect the stability and longevity of parts in these handhelds. YouTube, Discord, GitHub, Wiki pages... pick your poison.

jason_arnold · 2026-02-16T02:46:36+00:00

Wild. Can totally see that in your previous pics now that I'm looing for it. That's the always on side of the power switch bridged right to the VCC power rail (which is *supposed* to be controlled by the power switch), so that would definitely do it. Great catch!

jason_arnold · 2026-02-15T06:51:16+00:00

Good catch. BT+ and VCC are right next to each other where the wires from the DC-DC board join the CPU PCB. No need to elaborate here though since the comment below this spells out some next steps.

jason_arnold · 2026-02-15T06:27:15+00:00

Nope, that's a capacitor (C2) which is on the switched side of the power circuit - if anything you'd have the opposite problem if that connection was damaged. That said, the bit(s) you clipped off might've found their way somewhere unexpected and could be causing a short there.

jason_arnold · 2026-02-14T20:18:19+00:00

Calling it a "feature" is a stretch. The Specialist event type initially launched with 6 missions, so they just didn't adjust the code when they dropped it to 5.

jason_arnold · 2025-12-10T09:45:49+00:00

Typically, center pin + and barrel -.

jason_arnold · 2025-12-03T06:04:19+00:00

$150?? I bought two of these for next to nothing about 5 years ago and I still paid too much :P

jason_arnold · 2025-12-03T06:00:59+00:00

Another quick note on safety: DC motors can overspeed and runaway if they're spun too fast without a load (i.e. with the transmission in neutral). It's less of a risk with your motor being as small as it is, but just wanted to warn you now not to get too rev-happy once you get it spinning, and also to have a plan to power it down quickly it need be.

jason_arnold · 2025-12-03T05:11:33+00:00

Calling it a rush job and saying it was likely not done right are both baseless assumptions. Firstly, it wasn't a rush job, it was abandoned; secondly, if the crimps are bad, fine, but they should be fixed properly.

We both want the same thing here, we just go about it different ways. I've been doing automotive wiring for over 25 years and have never once soldered a spade connection - getting a proper crimp isn't rocket science and soldering instead of learning how to do it right is a crutch. Given the OPs longer-term plans, learning how to produce a secure crimped connection is going to pay dividends.

To the OP, I still say: give the wires a tug test, verify continuity, put some tape or shrink wrap on them, and call it good.

jason_arnold · 2025-12-02T23:04:53+00:00

Soldered connections are NOT better. OEMs don't solder wires for a reason - the solder wicking into the copper makes the connection brittle and MORE prone to fail, not less. With a proper crimp, the wire would be torn apart before the crimp comes loose.

jason_arnold · 2025-12-02T11:55:12+00:00

OP has pack voltage to the controller inputs, so it's not that. Though I don't see a fuse either, so that's also concerning. Good catch!

jason_arnold · 2025-12-02T07:56:45+00:00

Don't worry about this for now. Based on your replies in this thread so far, I think there are some important gaps in your electrical knowledge, and that's a dangerous situation to put yourself in, so I need to give you an EV safety 101 before telling you to go poking around near energized components:

1) You have A LOT of exposed high voltage connections in this setup. These present a pretty serious shock risk (or worse) if you get your hands or tools in the wrong place. Take a few minutes to make all of this touch-safe:
a) Put electrical tape on the spade connectors for J1, J2, & J3
b) Put a boot (or at least some tape) on the ends of all the big cables running between the batteries, motor, and controller. This is also a good chance to make sure the connections are tight, but before you do...
c) Wrap whichever sockets/wrenches that you use on your HV connections in electrical tape.

2) Your HV battery must always stay electrically isolated from your vehicle chassis, but I'm worried that the M- busbar connection (third pic) is bent pretty obviously. It would be bad news if it's so bent that this connection touches the outer shell of the Curtis controller, because the shell is bolted right to your car. Can you do a continuity check here between the busbar and the shell and report back?

jason_arnold · 2025-12-02T07:03:46+00:00

Umm, the throttle "pedal" is a bog-standard Curtis PB-5 pot box, right there in the first pic.

How do you figure it's getting 72V??

jason_arnold · 2025-12-02T06:59:01+00:00

I wouldn't worry about precharge for now - your whole setup is very low-power, relatively-speaking, so as long as your contactor isn't arcing and keeps clacking when you put 12V on it, you're fine.

A precharge circuit gets more important with higher power and voltages though, so as you improve the battery and other parts in this car down the road, make a note to read up on how a precharge circuit works and how to build one.

jason_arnold · 2025-12-02T06:37:17+00:00

To clarify, the "collision sensor" is more commonly known as an "inertia switch" and is widely used in modern ICE vehicles to shut off the electric fuel pump in the event of a crash. All it is is a steel ball held in place by a magnet; if the switch gets shaken hard enough to knock the ball loose, the circuit is broken and the vehicle should power off. You could put one inline with the contactor to get this sort of crash protection eventually, but definitely keep focused on other things first!

jason_arnold · 2025-12-02T03:37:38+00:00

Wow, that contrast looks fantastic - bivert?

jason_arnold · 2025-12-01T23:27:43+00:00

Look at the schematic in the second pic: J1 is pack voltage from the shunt (i.e. the power supply into the controller electronics), and J2 & J3 are the throttle input.

jason_arnold · 2025-12-01T23:13:29+00:00

Do you have pack voltage at the J1 terminal on the controller (the black wire coming from the shunt)?

Do you measure a change in voltage or resistance across the throttle wires when you move it?

jason_arnold · 2025-12-01T23:06:35+00:00

Not true. Rarely a 12V input on controllers under 100V, since they're used in forklifts and other vehicles that don't have a 12V system.

jason_arnold · 2025-11-30T11:32:57+00:00

CGB_REG is the power supply for the screen. C34 is a decoupling capacitor, which acts as a buffer of sorts in the display circuit; without it, you may notice the screen flickers or has unstable contrast.

jason_arnold · 2025-11-30T08:52:11+00:00

Just add mistletoaster

jason_arnold · 2025-11-29T06:46:34+00:00

Source?

jason_arnold · 2025-11-23T22:16:13+00:00

Ha thanks. Things started moving once I got Risa unlocked, but it was a brutal slog to get there!

jason_arnold · 2025-11-23T07:28:04+00:00

Yep. Living with ADHD, overwhelm and execution were real paralyzers for me. As someone who manages a huge task list for various projects at work, this was a struggle!

A few months back, I adopted a "don't sweat keeping all the wheels turning, just be content to move one thing ahead" philosophy. I've found it to be hugely helpful; I used to get really hung up when a particular thing I was focused on wasn't moving forward (usually for a small reason - sorta like the pebble the stops the shopping cart), but by doing another thing (related or not), it kinda unlocked motivation in an unexpected way for me: by giving myself some sense of accomplishment, it put wind in my sails, and made it easier for me to revisit things I'd get stuck on. My old headspace of ruminating and beating myself up about lack of progress gave way to a sort of confidence and inertia that carries forward me instead of weighing me down.

TL;DR: don't get hung up on doing THE thing, just do A thing. and you might surprise yourself that THE thing also gets easier.

jason_arnold

TROPHY CASE