T2 Gun Pots - test question...

modessitt

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I am working on a T2 with non-functioning guns. Both gunsites are stuck in the upper left corner.

When I opened up the gun bases, I found one wire off on the Y axis pot of the left gun, but the other three were wired up properly. I reconnected the loose wire and then checked the 4 pots with my meter. The one with the loose wire has a good 5K reading across the outer lugs, and smooth readings from the center to each outside lug as the pot turns. The other three pots show opens between all lugs, so I assume they are bad and will replace them.

Now - on the test screen for gun calibration, when I turn the good(?) pot, I get no change in the number for the Y axis. The fuses are all good on the Gun input board, and I don't see any problems with the connector. Do both pots have to be working for the gun to register? Or is there something else I should be looking at?

Thanks...

BTW - I should be able to pick these little 5K pots up from Radio Shack or Fry's, right? Even if I may have to trim down the shaft? And I guess the end needs to be beveled for the gear sleeve to turn with it?
 
AFAIK, you don't need them all to be working. If I remember I only had one gun hooked up when I was getting mine going at first. As far as those pots, I've heard you can do some work to a pot to make it work with T2. Otherwise, they are like $35 bucks from HAPP.
 
I read some posts about the radio shack pots so I went out and bought them for my T2 as my tracking was bad. Well, after hours of trying to modify just one I ended up buying 2 used guns on ebay and stealing the pots out of them. They did not have the same feel and range when I tried it. They are only about $2 though so you might want to try. originals or similar from Happ I have seen for $25-50 dollars each.

WD40 and cable lube seemed to refresh the old POTs for me.
 
I fixed it today. Turns out the pots were okay, but someone had messed with the wiring and had offset one wire in a connector between the driver board and the cpu. Once I fixed that, both my guns started registering properly...
 
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