Thanks. Yeah, I'm combining resistors. 3 to make the 497k, 2 to make the 250k, and 1 for the 2.2k. Either way, you answered my question.
I tore it apart once again, and put it back together. This time, I pretty much followed PMP's first schematic, along with my schematic from this link: http://www.atariage....s...t&p=1101980
(simply to get a better visual idea of what was going where)
And it works much better this time. I still get an OCCASSIONAL ghost down when I'm pushing up. But instead of one ghost down for every first up, now I'm getting a ghost down about once ever 7 or 8 times. I actually got past the pit in BC's Quest for Tires... which was virtually unplayable before. I also went ahead and reoriented the stick correctly (up is now up, left is left, etc...) So I'm about ready to call it complete and just live with the occasional ghost down. In all honesty, BC's Quest, which is unplayable in emulation and with the 5200 stick, works pretty well, and it was the worst before, so I figure all the other titles will be much improved. I think I'm going to go treat myself to some uh, testing now, and enjoy the fruits of my labors.
Thanks again, PMP, and everyone else, for all your help on this. I can't wait for some of the other DIYers around here to make this stick so we can compare notes and see if this problem is just me. The only thing I can think of is that I'm about 600 ohms off the 497k Ohm value. But maybe it is simply a matter of analog being a kinda tricky and imprecise beast, so what works on one 5200 may not work so well on another.
And I'd like to add, this stick, even with the occasional ghost down, kicks butt! On games that would benefit from a digital stick, the improvement so far is drastic. I played Gateway to Apshi last night for about 45 minutes. I've gotten further in Montezuma's Revenge than I've been since I was probably 12. There is a lot of wiring involved, but the payoff is completely worth it.
Edited by Paranoid, Tue Jul 18, 2006 11:52 PM.