The Color Vectrex lives!
For a little history on this machine, click here.
This little project got started while talking with Jay Smith at the Classic Gaming Expo 2001 in Las Vegas. He had brought the color prototype to display in the museum, and we got to talking about how it works, and how the phosphor was burned in the middle of the screen. After realizing that this probably didn't mean the tube was actually dead, he agreed to let me take the machine and see if I could fix it. He figured it was considered a non-working prototype anyway, so short of physically destroying it, what harm could I do? :)
So, I brought it home, and spent a couple of days very carefully checking things out. Right off I noticed several wires that were cut, one POT that was broken, and the yoke on the CRT was broken (all the different coils were kind of moving independently of each other, not a good thing, but not fatal). After repairing everything (except the yoke), I carefully powered things up one piece at a time, checking voltages, and when I powered it all up, I heard the familiar buzz, and then the Vectrex tune! Yay, it worked! Nothing on the screen though... Damn... Well, maybe... *squint* So I turned off the lights, here's what I saw:
I know that's hard to make out, but then again, it was hard to make out... :) But most importantly, the CRT worked! Time to break out the scope and really get into it. After 2 more days of working on it (thanks to whoever is responsible for scanning in the troubleshooting guide, that was extremely helpful!), replacing parts and scavaging a yoke from another Vectrex, here's the results:
The pictures aren't great, but this proves it works. :) The
middle screen on both sets is a normal Vectrex for comparison. Top pic is with
room lighting on, bottom with it off. Before I resoldered some bad connections,
it would come up in yellow sometimes, so I got some pictures in yellow just
to prove it's different colors. (I can see green during the little flash just
when you turn it off sometimes).
There it is, Pole Position in red and yellow! :) I figure the extra logic chips were added to allow the programmers to select which of the three colors to use at any time, and the neutral one is red, so that's the default for all the normal Vectrex games... So, if nothing else happens, at least you all will get to see Mine Storm in red at the next CGE or where ever this machine is displayed next. :) I can probably rig up a switch to manually switch it from red/green/yellow as well. It's still in need of some fine-tuning and maybe a cap-kit (which I'll have to build up myself since it's not the same as a normal Vectrex). And for those that saw it at CGE, I've got it all physically re-adjusted so the screen is in straight, and tight (it was on the verge of falling apart at the show).
Happy Vec-ing! ...