Exactly :) just as @cheesestraws said, both power and CRT circuits are integrated into one board, there's no way to wire or plug that PicoATX thing in at all without removal of certain parts on the voltage rails.
Sadly that was not the case with my early investigation on this project due to how integrated the analog CRT and power boards are. I had to desolder anything below the lower half of the analog board to power up the CRT circuits cleanly.
The earlier classic Macs can get away with a PicoATX since...
It should be possible! I mean this thing runs on a single USB-PD charger right now so integrating a better and modern power supply circuit on a brand new PCB would be really kickass!
I also think everything except the flyback and the CRT connectors can be replaced with SMD resistors and probably...
I've modified `dtparam=vactive=342,vsync-invert` from 342 to 384 to have a proper 4:3 aspect ratio. After adjusting the vertical size potentiometer it seems to work well!
Also the analog board voltage hooks schematic buried in the previous thread:
WARNING: If you don't know how to deal with high voltage stuff, please stay away from this thread. I am not liable for any lethal/non-lethal injuries or damages resulting from the use of this information.
Can't believe I forgot to post it but here's my config.txt for the rpi 4 if anyone wants to replicate:
kernel=rpi4-u-boot.bin
dtoverlay=upstream-pi4
arm_boost=1
dtoverlay=vc4-kms-v3d-pi4
dtoverlay=cma,cma-256
max_framebuffers=2
arm_64bit=1
gpu_mem=16
boot_delay=0
force_eeprom_read=0...
After more than a year of service as a Raspberry Pi 4 home server, It's still going strong :) I've added a adb2usb converter courtesy of https://github.com/tmk/tmk_keyboard/tree/master/converter/adb_usb
The CRT has been continuously running ever since, it's noiseless and only consumes 30W of...
WARNING: If you dont know how to deal with high voltage stuff, please stay away from this thread. I am not liable for any injury or damages resulting from the use of this information.
With that out of the way, this is the culmination of all my mods to make the Early Classic Analog Board run...
I will list down the mods in a modified schematic of EAB later soon, hopefully folks can try it to save classic analog boards that are screwed by their broken PSU circuits :)
Yes, i retained the LM317, but i removed the 12v reg for efficiency's sake and combined all 12v rails into one, including the one on the heater, the 12v rails on the deflection IC and the softstart RC circuit in LM317's ADJ pin. I supplied the usb-pd's 20v to the input of LM317 and it seems to...
Okay, after some tweaking, it seems that the LM317 and its adjacent passives are important for limiting the current of the 31v rail. Now it's fixed, hopefully.