Sega Game Gear
I bought this Sega Game Gear many, many moons ago, while we were still living in Sacramento, California. It was supposed to be a gift for one of the kids, but it was in the boot of the car when our car got stolen, and though we recovered it, the kids didn’t seem too interested in it so I ended up keeping it. I’ve basically never played it - we have one game (Jurassic Park) which I don’t recall enjoying that much (might have something to do with why the kids weren’t interested), and it more or less sat in the laundry room at the house on Vine St for nearly ten years until I found it, luckily, on one last pass through the house before I gave up ever finding the things I was missing.
Bringing it home from the US during our last visit, I tried getting it working. It wouldn’t work off batteries, but I did get it working off a 9v power supply, sort of. It booted, but the screen looked shit, there’s no sound, and it died shortly thereafter. A recap is obviously in it’s future, but our local retailer wanted too much for capacitors to warrant the effort.
Later, on a whim, I started playing with it again, determined to work out why it won’t work off the battery. Checking the output pins of the power board with the mainboard unconnected, pins 1 and 2, which are supposed to be +5VDC, were only at about 1.5v. Pin 9, is supposed to be boosted to +34VDC for the backlight, was at a mere 3V or so. But most tellingly, pin 7 (VBAT), which is supposed to connect directly to the battery for the GG to tell it’s voltage, was only about 1.5v too. After tracing around the power board for a while, I found that the connection that switches the batteries away when the PSU is connected (so as not to charge them) was very poor. The PSU connector will need replacing (it’s awfully corroded), so I desoldered it and bridged the two pads, and the voltages were in spec - it now works (for some definition of “works”) off batteries.
Still needs a recap though, which at the time of writing is not done.
Replacement Capacitor List: Main Board - VA1 837-9204
I’ll format these better later:
C1 33uF 6.3V C4 10uF 16V C11 10uF 16V C14 10uF 16V C42 10uF 16V C43 22uF 6.3V C45 4.7uF 35V C47 68uF 6.3V C49 100uF 4V C54 0.47uF 50V C55 0.47uF 50V C68 100uF 6.3V
C1 100uF 6.3V C2 100uF 6.3V C3 100uF 6.3V C5 47uF 4V C7 47uF 4V