A Fire Breathing Dragon 32 Retrocomputer Restomod
Drygol of RetroHax.net got their hands on a Dragon 32 and brought it back to working condition with a few mods.
The United Kingdom already had a number of well-respected computer manufacturers in the early 1980s, including Acorn, Tangerine, and, of course, Sinclair. But they were all English companies, and Wales lacked its own homegrown 8-bit microcomputer. To remedy that, Dragon Data, Ltd., which was based of Port Talbot, Wales, began selling its Dragon 32 home computer in 1982. Despite being decent computers, they didn’t sell especially well and are somewhat rare today. Drygol of RetroHax.net got their hands on a Dragon 32 and brought it back to working condition with a few mods.
The Dragon 32 is often considered a Tandy/RadioShack TRS-80 Color Computer clone, as both were designed around the same Motorola datasheet — a datasheet which Tandy created in partnership with Motorola for the 6809 processor. The Dragon 32 is mostly compatible with TRS-80 CoCo assembly language code, and can run the TRS-80 CoCo ROM. Many Dragon 32 software titles are even direct ports that retain the “Tandy” name. That also means that virtually all of the chips are interchangeable, which can be very helpful for repairs and mods.
Before Drygol could get to the mods, they first had to get the computer working. The biggest challenge was simply providing power, because the odd setup has an external transformer that puts out 8.5VAC and 28VAC through a DB9 socket. That is then converted to 12VDC, 5VDC, and -5VDC internally. Drygol was missing that power supply, and so they ditched that original setup altogether. Instead, they replaced the DB9 socket with one for a Commodore Amiga power supply. That power supply can connect directly to the motherboard and doesn’t need to go through the Dragon 32’s internal power supply.
The Dragon 32 was able to boot up after that, but the picture quality was still very poor. It turns out that there was a bad SFC2318 op-amp chip, and replacing that chip restored the composite video signal to a good quality. Drygol kept the RF modulator as well, which is fed from that composite signal. The final step was to upgrade the RAM from 32K to 64K — a job that requires a bit of hackery, but which is well-known in the Dragon community. With some thorough cleaning , Drygol now has a nice, upgraded Dragon 32.
Drygol's computer came with a joystick in poor condition, which was repaired. But Drygol also created an adapter to utilize Atari and Commodore joysticks to make gaming more pleasant. The addition of a CoCo SDC makes it possible to emulate a floppy disk drive and load up software. Purists may not approve of the PSU modifications, but they do seem to be effective.