First System: N64 portable - I am going to try to make this first because there's a ton of visual guides to get me started and adapted to properly crafting a solid piece of machinery. I want to learn to do this right and really hone my skills.
This will be a very detailed work log.
Goals:Make very small
4+ hrs battery life
Include a headphone jack, volume controls, rumble pack/ memory card, expansion pak, av tv connector, charger/batteries, 3 controller ports
Parts:MB - N64 - PURCHASED ($10)
SCREEN/SPEAKERS - Toshiba 7" Portable DVD Player - PURCHASED - ($25) (has av in/out so i assume it works)
CONTROLS - GC joystick (PURCHASED), PS1 triggers (PURCHASED), Gameboy d-pad/A/B/start/select buttons (PURCHASED), n64 c buttons (PURCHASED)BATTERY - tbd
CASE - Most likely will design + commission someone once all parts are trimmed and wired
INTERNAL - rumble pack, memory card, and expansion pak, possible led lights for joystick/logoTools:Dremel + drum sanding heads/blades/drillbits (PURCHASED $20)
Screwdrivers (PURCHASED)Game Bit Screwdriver
Wires
Soldering Iron
Solder Wick
Capacitors/Resistors
Pliers
Pinsers
Wire Trimmers
Multimeter
Electrical Tape in multiple colors
Glue Gun
Sandpaper/Blocks
ScrewsI'll be getting started on my work log as soon as my dremel arrives!
NOTES: the screen is 7" but I might make the whole thing horizontal anyways. This way it'll be pretty long, giving it a pretty unique shape with ease of working and game play. Hopefully it'll be short but long.
Here's my ideal N64 portable case layout (I used all the right dimesnions for a 7" screen):


EDIT: Disassembled a 1st party controller. The joystick has already been worn out.
