Making DOS and CP/M 5.25″ Boot Disks with Commodore 128 and 1571 Floppy Drive

Did you recently get a new MS-DOS, KayPro IV, or Osborne 1 computer but no boot floppies?

If you have a Commodore 128 and a 1571 floppy drive, you might already know that you can read and write certain CP/M floppy formats while in CP/M mode. This is because the 1571 floppy drive can read and write two types of disk encoding schemes. GCR (Commodore, Apple, etc.) and MFM (common on CP/M and DOS platforms).

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Modern Upgrades for the Hayes Chronograph

Hayes Chronographs

Until recently, I had no idea what a Hayes Chronograph was. I didn’t even know it existed until Bill Lange (@BillLange1968) posted a picture of one on Twitter that linked to a wonderful article he wrote about them. The name Hayes was instantly recognizable though, being the inventors of the Hayes “AT” Command set that has found a way into just about every modem since. The shape was also familiar, a bigger version of the same case used in their Smartmodem 300. This was different. It had a beautiful vacuum fluorescent display (VFD) that was showing the current time and day of the week. I was hooked. I needed to buy this. What a wonderful trophy from the soon to come BBS halcyon days.

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Atari Portfolio Serial Interface: How To Get Terminal Software

I’ve had an Atari Portfolio HPC-004 for a couple of years now. It’s a slick little palm-top: solid state memory, MS-DOS compatible, 4 AA batteries as power source. It also has a docking slot on the right side for extra peripherals. This enables you to add communications ports that are otherwise lacking like a parallel or serial port. I’ve been seeking a second hand serial interface (HPC-102) for some time but have come up empty. I decided to instead purchase one new.

Atari Portfolio and Serial Interface
Atari Portfolio and Serial Interface
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Convert a Commodore 64 from NTSC to PAL format

If you’ve ever used a NTSC Commodore 64 for any length of time, you’ll quickly find out that many games and demos you try to run on your machine sometimes exhibit strange graphic or sound glitches or just refuse to run properly at all. It’s most likely because the program you’re trying to run was originally written on a PAL machine. With it’s different VIC-II chip generating a different master clock signal, the PAL C64 has a few more cycles available per frame than the it’s NTSC counterpart. Tightly coded loops in programs rely on a certain number of cycles to be available. And when they’re not, well, it doesn’t work as intended.

If you happen to own a C64 “short board” system, you can convert your NTSC machine to a PAL one easy. If you are unsure which board you have inside, you can open it up and take a look or make an educated guess by reading this site. A SID 8580 is usually a good sign you have a short board. But please make sure you confirm your board type before you begin. The VIC-II types (65xx vs 85xx) are not interchangeable!

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Commodore 1520 Plotter X/Y Gear Repair Guide

Commodore 1520 Printer/Plotter
Commodore 1520 Printer/Plotter


NOTE! New replacement Alps gears for the Commodore 1520, Atari 1020, etc are now available! Click here to order your set.

You’ve just unpacked your new Commodore 1520. It was most likely sold as untested, as-is or condition unknown. You plug in the cable, turn it on, and it buzzes and grinds for a couple of seconds then the red LED on top flashes. Silence. You might be lucky and get a little movement on the print head.

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RS-232 for Commodore PET and Dialing a BBS over WiFi

Commodore PET running WordPro Four Plus.
Commodore PET running WordPro Four Plus.

I’ve owned a Commodore PET* 8032 for a few years now. I’ve been able to download and run many different programs for it, like WordPro you see above. But one thing always remained elusive. I’ve long wanted to connect it to a standard RS-232 device and use it as a terminal. The PET’s classic shape, green monochrome monitor, and 80 column display all lend itself perfectly as a terminal.

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LumaFix64: Commodore 64 with less stripes

Commodore 64
You might be asking yourself, less stripes? No, not the colorful stripes on your breadbin badge. We’re talking about the stripes on the video image. The same stripes that we’ve all become accustomed to over the many years of playing Commodore 64 games, watching demos and carrying on with modems and BBS’s. These stripes, which are actually interference, come in a variety of flavors: horizontal, vertical, and checkerboard patterns. The intensity of the stripes also varies from machine to machine. Some say with that these stripes become even more apparent when using a C64 with a modern LCD monitor.

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SX-64 Short Expansion Board

SX-64 Expansion Boards, original and new, front and back views.
SX-64 Expansion Boards, new (top) and original (bottom), front (left) and back (right) views.

If you were following along with my previous post about converting an SX-64 to a DX-64 by adding a second floppy drive, you’ll know that the process isn’t without it’s problems. There are some irreversible changes that need to be made to the case to accommodate all the extra equipment.

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Converting a Commodore SX-64 to a DX-64 Dual Drive

Commodore DX-64 (converted from SX-64) Many floppy. Very retro. Such storage. Wow. #doge #c64
Commodore DX-64 (converted from SX-64)
Many floppy. Very retro. Such storage. Wow. #doge #c64


The SX-64 was Commodore’s portable version of the best selling C64 computer that wrapped the C64, a 5″ color display and a 1541 floppy drive into one case that loosely resembled a Kaypro. They were also called luggables because, well, they are quite heavy. Despite folks calling them rare, they litter eBay very frequently and command a premium price.

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