Spykerwolf's build log - GBZ - custom parts

[sumitverma]

i dont need headphones i just soldered the amp

[Spykerwolf]

Hi guys. I'm hoping someone could help me wire up the volume wheel. It's 5 stereo, but only hooking up mono.
So far the headphone jack works & the speakers work whenever I unplug the headphone jack.

Headphone jack: PJ-325

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Volume wheel: B103

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Amplifier: PAM8403 green

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The wiring is:
Low pass filter - Headphone Jack - Amplifier - Speaker.

I currently have the volume wheel connected between L in & Speaker - on the amplifier. Everything is connected to the left output speaker in mono.
The volume wheel is working if it's not completely muted, but makes a horrible noise when muted.
The same noise occurs when I plug something into the headphone jack.
I tested using a different potentiometer & got the same issue, so much be wiring?
Any advice would be appreciated, thanks!

This is the sound it makes:
https://www.youtube.com/watch?v=QSOrxcnuXq4

[Spykerwolf]

Turns out through many koffie breaks & swear words...the problem was the potentiometer.
Connected a different one (5k) and it's working as expected. Now to wait 3 months for my replacement ali express one to arrive.

[Spykerwolf]

Made some progress since my last post:

- Drilled extra holes for the buttons & tested the controller board

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- Salvaged the button wells from an aftermarket SNES controller

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It was really tricky getting the button wells right as they broke when I removed them.

[Spykerwolf]

I realized I installed the display the wrong way as it had part of the screen showing behind the case.
It also had a silver bit that needed to be taped up - something I couldn't easily do without removing it first:

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It was a mission getting it out & I read alcohol should help with the hot glue. I used some nail polish remover to correct the screen.
However I didn't realised it was a bad idea & some of it got into the screen. Luckily it evaporated & most of it disappeared, however it did damage the screen a bit, but nothing too major:

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[Spykerwolf]

Gave up for a few weeks & gave it another go. Unfortunately I didn't take much photos:

- Low pass filter created on breadboard & then transferred over to a pcb.

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- Button PCB installed & wired up to the rpi zero w
- Buttons salvaged from a SNES controller.

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[Spykerwolf]

- Installed the speaker, 3.5mm jack, amplifier, volume wheel & low pass filter.
- It's a bit of a squeeze but the case does close.

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[Spykerwolf]

Battery wise - I got a power bank & removed the li-po battery:

- Removed the power bank cover & used baking powder to help make the sticky stuff not sticky - probably the most nerve wrecking thing I've done

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- Had to grind down some of the plastic in order to make it fit

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- The little battery cover catcher also needed to be shortened as it was pushing against the battery

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I think the last things remaining are:

- Install USB 2.0 slot for charging.
- Install & mount my power charge/discharge - to be honest no idea how to wire this yet.

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- Mount raspberry pi with micro sd facing outwards.
- Install L & R buttons once I receive the switches

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- Get a faulty game & install the pcb into the cartridge case
- Install the power switch & wire it up (still waiting on aliexpress)

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- Wire up the battery to the power charge/discharge & raspberry pi - no idea how to do this. Can I cut the leads at the moment in order to remove the pcb?

[Sudafed]

Regarding that powerbank module... i had the same but it was flaky and i replaced it with a similar one from aliexpress (mh cd42) which solved most issues. Either way the basic wiring is simple. Just connect bat, vin, vout and gnd. Then you will need extra push button to start or stop the integrated step up converter. I also connected that button to a gpio so that i can run a shutdown script on long press. Last thing i did was wire a 1f supercap parallel to the output so that the pi doesn't reset when pulling the charge cable.

[Spykerwolf]

Regarding that powerbank module... i had the same but it was flaky and i replaced it with a similar one from aliexpress (mh cd42) which solved most issues. Either way the basic wiring is simple. Just connect bat, vin, vout and gnd. Then you will need extra push button to start or stop the integrated step up converter. I also connected that button to a gpio so that i can run a shutdown script on long press. Last thing i did was wire a 1f supercap parallel to the output so that the pi doesn't reset when pulling the charge cable.

I'll see if this one works, if it doesn't I'll order an mh cd42 too.
When you say extra push button, do you mean the on/off switch for the GBZ?
So wiring wise I'm thinking:

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GBZ - 5V/GND to VIN/GND
LiPo Battery 3.7V/GND to BAT/GND
'Output' / VOUT - This this where I get confused - what do I connect here?

The plan is to have a barrel connector charge the device using the inbuilt DC hole. The power on/off switch will also be in this circuit.
Would the barrel connector be connected to the VOUT/GND then?

Or would it be connected like this:
USB to barrel plug 5V/GND to VIN/GND
LiPo Battery 3.7V/GND to BAT/GND
VOUT/GND to 5V/GND on raspberry pi zero.

Thanks for the help...Sorry I'm a beginner.