Soldering for Super Sound

I recently got the ADAM-beige variant of Opcode’s Super Game Module (SGM). It’s a great expansion for the Coleco ADAM (or ColecoVision) and probably my favourite thing about it is its amazing audio capabilities. Games that are SGM-enhanced can feature incredible music and sound effects thanks to the SGM’s sound chip.

Unfortunately there’s a slight problem enjoying that great sound thanks to a design flaw with ADAM’s wiring. The misplacement of a single wire that runs from the 7-pin DIN (A/V port) results in unbalanced audio. Essentially, ADAM’s own audio works fine but the audio produced by any side-expansion units like the Super Game Module or Expansion Module #1 would have very low volume. That left me with two options:

  1. Turn the volume on my TV way up when playing SGM games and deal with resulting humming/buzzing it produces.
  2. Fix the wiring. Using a soldering iron.

After a week or so of pretending I could live with option one I eventually worked up the nerve to attempt the fix. John Lundy wrote a helpful document that sums up the issue and how to fix it. For experienced hardware tinkerers or engineers this is a very simple job. As for me, Iā€™d honestly never used a soldering iron before so it was a daunting task!

After dismantling my ADAM ā€“ my one and only ADAM that I’ve had since the 80s ā€“ I found the green wire that needed relocation. I first removed the blob of dried up hot glue that covered the spot where the wire was connected to the board. Here’s what I was looking at:

I hesitantly heated up the soldering iron and got to work trying to remove the wire. After after a few seconds of trying (and burning the green covering of the wire in the process) I decided it’d be easier to snip the wire as close to the board as I could instead. See the capacitor located at C88 in the photo? The fix is to solder the wire to the right side of that capacitor. As I said earlier I’d never worked with a soldering iron before. I was nervous! My hands were shaking so much and I couldn’t get the solder to hold the wire in place. Eventually, my persistence paid off and I got the job done. Here’s the “after” shot:

I know… definitely not the neatest job! The slight scorch marks on the capacitor had me worried that I might’ve damaged it. I reassembled my ADAM and powered up. I was relieved when the familiar beep of ADAM’s SmartWriter greeted me so I excitedly fired up an SGM game (Thexder) and soaked up the glorious sound! Mission accomplished.