More retro goodness (Repost)

(Originally posted on Dreamwidth Dec. 7th, 2018)

Well, let’s see. I’m a LOT better at all this stuff. I have the A1200 booting, and more! It has:

  • A proper LCD monitor that supports the wonky frequencies the Amiga uses (15KHz vertical refresh).
  • An SD to HDD adapter, with an 8GB SD card in there pretending to be a couple of hard disks.
  • A keyboard adapter allowing me to use an old PS/2 keyboard with it.
  • A mouse adapter that I designed and made that allows me to automagically change to a joystick in the same port.
  • A Virtual Floppy drive (Works from USB thumbdrives full of disk images) that I flashed the firmware of and added all the extras such as
    • An OLED screen that shows me which image I’m using.
    • A pizeo speaker that simulates the buzzes and clicks of the original.
    • A rotary selector that makes disk choosing easy.
  • A design for a laser cut case to hold it all, only pending the Artifactory fixing their damned lasers again.

I also purchased a batch lot of Commodore stuff and now have:

  • A Commodore 64 (More on this later)
  • A Vic 20 (With a whole bunch of carts)
  • An SX64 with what appears to be a dead PSU
  • A Commodore 128D. This is a “Work in Progress” as it has a problem. I’ve recapped it but it fails when I plug the PSU back in. Basically I need to take it to the Artifactory and plug it into the bench PSU.
  • 2 Floppy drives, one of which definitely works, one of which needs some more love.
  • 2 Printers(!) that I’ll need to gove some love to once I have everything else under control
  • A C128 Monitor which has a loud scary crackle.

I had to build a new PSU for the C64 and Vic20 as the “stock” ones are notoriously bad. They have a nasty “fail to high voltage” that’s really efficient at cooking chips. This was an interesting challenge but I got there in the end. I’m always a bit squirrelley around AC voltage. 

I then purchased a job lot of dead Commodore stuff. 3 C64s and another FDD plus a joystick. This was for a fraction of the price I paid for the batch job above, but that was cos it was all failed stuff.

So initially I plugged all three C64s in one by one and documented the faults. Two had a problem where I got monitor sync and nothing else. One had zip. Nada. Nothing.
Doing standard fault finding I found the first two had no DC voltage and the second had no AC voltage. Turns out the switches on C64s have an effective lifespan of about 20 years… These were 1986 models. 
I had to desolder the switches, which turns out to be one of those understatement things like “And then the atomic bomb exploded” as Commodore must have hated their service technicians. There is an RF shield that’s soldered on to the motherboard. I manged to desolder the RF Shield through a combination of my soldering iron on maximum and using a set of dental picks as prys. Once THAT was off my desoldering station made quick work of the switches.
I desoldered, cleaned, greased and assembled and suddenly 2 of the 3 were booting! The third was now getting sync.
Of the two booting ones, one was perfect. It’s now in my stack of “working” gear waiting for a recapping. I’ll probably sell one of the working ones.
The other was showing rainbow garbage, an issue consistent with bad RAM. This led to more purchases.
I next purchased a couple of cartridges (Dead Test, 60 in 1) and some bits and pieces.

My next project was to build a pair of paddles for the C64. Unfortunately I haven’t had a chance to test them yet.

I used the Dead Test to confirm which chips were bad in the dead RAM c64 and I decided to use the OTHER dead c64 as a parts donor (As it was showing fatality on one of the key chips)

I have, however, been unable to desolder the RAM off my sacrifice board! I’ll try again this weekend if I can but it’s more challenging than I would have expected. After half an hour I’ve manged to get ONE of the chips to sit at a jaunty angle and that’s it.

Still to do:

  • I need to build a pair of 1541 ii PSUs. I have the parts for one but will need to order more bits.
  • I need to recap all of the c64s
  • I need to build more PSUs for c64s
  • I need to get to the Artifactory and test what’s wrong with the c128D and get it working!
  • I need to get my c128D monitor to the guy who has offered to have a look at it.

Stuff “in the mail”

  • Utility cart (Including Fastload, Freeze and loads more stuff)
  • Pi1541 (This is an awesome doodad you plug into a Raspberry Pi and it emulates a Floppy Drive.





One response to “More retro goodness (Repost)”

  1. ilike8bits Avatar

    The paddles worked first try. Great for Arkanoid.

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