Recent content by RetroTheory

  • Nominations will close March 25th. If you'd like to join the board and influence how TinkerDifferent runs in the next year, put your name in now!
  • Hey Guest, MARCHintosh 2026 is upon us. Check out community projects, join GlobalTalk, and have fun!
  1. RetroTheory

    Big Maclock. A software inspired version of the desk toy clock

    Since I posted the source code on github, I thought Id make this new post I made a program with Retro68 cross compiler with a strange likeness to the like clock Maclock. Watch out for the clock bug, where DAY does not match date. I find 1998 works for this year. @This Does Not Compute gave...
  2. RetroTheory

    MARCHintosh 2026 Projects

    This is really a useless project but I am having a bit of fun after figuring out how to interact with serial data A Digital Multi meter logger , specifically the one I have, the Uni-t UT61E The meter has an optically coupled rs232 out, and after a bit of cable modding I was getting serial...
  3. RetroTheory

    Macintosh Plus - Weird Startup Problem

    Hmm, how many chips on the SIMMs ? if its 2 or 3, its kinda hit or miss if they work. 8 or 9 is more common to work, having said that I have 2 chip 30pin SIMMs in my Plus. https://support.apple.com/en-asia/112183
  4. RetroTheory

    Macintosh Plus - Weird Startup Problem

    Have you checked the RAM is correct and matches the cut resistors config on the board ? Sometimes resistors are cut and then RAM is downgraded which can lead to odd behavior
  5. RetroTheory

    MARCHintosh 2026 Projects

    I made a program with Retro68 cross compiler with a strange likeness to the like clock Maclock. Watch out for the clock bug, where DAY does not match date. I find 1998 works for this year. @This Does Not Compute gave me the idea when he converted the clock into a vintage Mac, I wanted to see if...
  6. RetroTheory

    Can You Put a White Phosphor CRT into an IBM 5155 (Portable Personal PC)?

    5155 monitor system, 12v composite video input I took the yokes off . and kept the mac yoke with the Mac. The 5155 tube has the anode cap on the opposite site with respect to the end connector. I had to extend the wires to rotate the board so it would fit with the anode cap in the...
  7. RetroTheory

    Can You Put a White Phosphor CRT into an IBM 5155 (Portable Personal PC)?

    The naked CRT is the CRT module for the IBM 5155 , but all it needs is 12V and an ntsc composite video signal. The video is inverted with CloseView , with magnification turned off , but leaves a tell-tale zoom box see bottom right , its also a little slow. There is an invert video program...
  8. RetroTheory

    Apple IIGS RGBtoHDMI + Apple Macintosh Monitors

    Unfortunately not easily. You would need a composite to sync separated video. However it could be a project for rgb2hdmi with 15khz rgbhv video out to cpc , I have never tried that output mode
  9. RetroTheory

    Can You Put a White Phosphor CRT into an IBM 5155 (Portable Personal PC)?

    This is my tube swap between a mac and a 5155 monitor chassis , as long as crt band mount is the same you should have no issues
  10. RetroTheory

    Reviving a sad looking Quadra 840av

    Wow great job, congrats on getting it going again. That board was with a stack of 4 840AV boards that originally was part of Apple waste back in the day when the 840av was current. Apple were less careful with their waste back then and these were thrown out due to cosmetic issues. At the time...
  11. RetroTheory

    Happy 40th! [ATTACH]

    Happy 40th!
  12. RetroTheory

    Design68: A 65% replacement keyboard using AppleDesign controllers

    There is also this clone made by ALPS (MEADB-), But inside we have a familiar IC. Not sure if the membrane layout is the same though
  13. RetroTheory

    Design68: A 65% replacement keyboard using AppleDesign controllers

    Great project , I have a few different ones Made in Czech Rep. 3 Screws on base Assembled in Thailand, 4 screws on base
  14. RetroTheory

    Macintosh IIsi - VGA Video?

    The VGA monitor config is not available on the IIsi, best to select something like "Apple Macintosh Color Display" or any of the monitor types here without the '*' https://bitsavers.org/pdf/apple/mac/monitor/monitor_sense/hw_30.pdf and hope the monitor can do composite sync / sync on green
  15. RetroTheory

    BlueSCSI v2 - DaynaPORT WiFi!

    Great work , I got a chance to try it out today on the Powerbook 180. Speed is about 30K/s. I coudn't pin it down, but it seemed I had to ping out from the powerbook with MacPing to get the network to go live. Will do more testing ..