I have two dead Commodore devices here, that a user asked me to repair. A 1541 floppy disk drive and a bread bin C64. The drive’s motor spins indefinitely and the LEDs don’t come on. The C64 has a black screen. So let’s get cracking, and repair both! With the C64 I made a couple of wrong turns, but in the end all turned out well! The 1541 had some other idea in store for me, and turned out to be a bit on the spiritual side…
The Horror: GameBoy Backlight Mod
The original GameBoy (DMG) had not the best LCD display that one could wish for. Most importantly it was a reflective only display, which required substantial amounts of external light to be visible. A friend sent me their DMG with the request to install an LED backlight mod. I thought: how hard can it be? Well, you be the judge of it…
Let’s Code MS DOS 0x31: ANSI C Data Types
The C programming language has only few builtin data types. But for a beginner those can be a bit confusing. So we will have a look at what data types are offered, and what kind of new datatypes you can build with C.
NEW Low Ripple 7805/7812 Drop In Regulator
Not even two years ago I published a video about the DR323 / DR78xx switching regulator by Mr Floppy, which is a replacement for the linear LM323 and 78xx series of positive voltage regulators. Their main advantage was their extremely low ripple, compared to other solutions such as the ezSBC. Now Mr Floppy has developed v0.2 of the regulator, which has some small improvements, and removed the surface mount coaxial port for probing. Instead he developed the Checker Board, which can be used to do accurate probing of TO3 voltage regulators.
Let’s Code MS DOS 0x30: VGA 3D Textmode
The EGA and VGA card can do a lot of magic tricks in textmode. This time we will investigate how you can draw a rotating 3D cube overlayed on normal text by utilising the EGA/VGA feature of a second character set.
Let’s Code MS DOS 0x2F: Mandelbrot Fractal
Everybody knows the Mandelbrot set. It is one of the most famous fractals. And it is easy to code! At least if you don’t care about speed… So let’s try to code it for ancient MS DOS PCs with VGA cards! And there will be color cycling!
Pico DRAM Tester
Eric Schlaepfer aka TubeTime has released an open source tester for vintage DRAM ICs. It is based on the fabulous Raspberry Pi Pico 2 microcontroller. It supports even older chips that use -5V and +12V. I ordered PCBs and the components for building the tester, so let’s warm up the soldering iron and build something!
FG 100 DDS Function Generator
A function generator can be a great debugging tool for digital and analog circuits. There is a very cheap one floating around that’s called the FG-100 DDS. What are its specs and is it any good?
New SID Replacement: Kung Fu SID
The MOS SID is the sound chip of the C64. Sadly they are no longer in production, and the ones that do exist start to fail. There are several replacement solutions out there, with varying pricepoints and sound quality. Now there is a new contender, fully open source hard- and software. It goes by the name of Kung Fu SID – promising great emulation and a price that’s hard to beat. Does it deliver…?
New Homebrew Sound Card: Sonic Buster 8
It’s been a long time since the last homebrew sound card we had on this channel! LABS is back with another iteration of the Blaster Board called the “Sonic Buster 8”. One improvement is that it now uses a genuine OPL3 chip for the FM music. Furthermore it is all SMD components and hence very compact and will fit also in cases where space is an issue. But is it worth the money? How does it hold up against other homebrew sound cards?