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Zebra

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I wanted to ask if anyone here knows enough about light gun repair / maintenance to offer some advice on how I might fix accuracy issues on a couple of my guns?

I bought a number of 3rd party recoil guns but every single one I tried has issues with teleporting crosshairs and, as a result, poor accuracy. My official Namco Guncon 2 guns, on the other hand, have perfect accuracy and tracking. They are as good as (or better) than any arcade light guns I have used. I would like to achieve the same performance from my recoil guns....

So... does anyone know what causes jumping / flashing / teleporting crosshairs on light guns? and can it be fixed?
 
Poor quality components, or poor design.

Part of the reason Namco's guncon 2 works so well, is it obtains the sync signal from the ps2 to the tv, and ties that into the gun.

They use the same tech in their arcade game guns as well, on games like Time crisis 2 and 3....the output from the game is sent to the io board, which feeds and interacts with the gun.

No other light gun has ever felt quite so accurate.
 
Poor quality components, or poor design.

Part of the reason Namco's guncon 2 works so well, is it obtains the sync signal from the ps2 to the tv, and ties that into the gun.

They use the same tech in their arcade game guns as well, on games like Time crisis 2 and 3....the output from the game is sent to the io board, which feeds and interacts with the gun.

No other light gun has ever felt quite so accurate.
All Guncon and Guncon 2 compatible guns connect and work the same way as the Namco name brand ones. I.e. You connect the guns to the composite video or composite sync line.

There is just something about the Namco design that gives you stable crosshairs that don't jump around.
 
My bad...i've never seen another console gun that hooked to sync, like the guncons.

In that case, maybe look for dead caps on your optic board for the gun?
 
My bad...i've never seen another console gun that hooked to sync, like the guncons.

In that case, maybe look for dead caps on your optic board for the gun?
I believe that the issues are present even when they are new. You might be on to something with the caps though. Someone on another forum said something about adding extra caps somewhere to fix accuracy issues. I'd give it a try if I knew where to solder them to and what size is needed.

My other thought was to try replacing the sensor board with one harvested from a Namco gun if it is compatible with the main board on this Jolt gun. The main board controls recoil so that can't be replaced as easily.

Btw, I believe that all light guns require a sync signal to work. The only difference between systems is where you attach the sync line. The SNES, Genesis and act labs (Pc) guns all had seperate signal box.
 
My bad...i've never seen another console gun that hooked to sync, like the guncons.

In that case, maybe look for dead caps on your optic board for the gun?
I believe that the issues are present even when they are new. You might be on to something with the caps though. Someone on another forum said something about adding extra caps somewhere to fix accuracy issues. I'd give it a try if I knew where to solder them to and what size is needed.
My other thought was to try replacing the sensor board with one harvested from a Namco gun if it is compatible with the main board on this Jolt gun. The main board controls recoil so that can't be replaced as easily.

Btw, I believe that all light guns require a sync signal to work. The only difference between systems is where you attach the sync line. The SNES, Genesis and act labs (Pc) guns all had seperate signal box.
What are you connecting the guns to? genuine arcade hardware or hacked to a PS2 or something similar?

I'd start by comparing the genuine Namco optical board to the third party ones.

Some info in this thread here , it is 10 pages long but Julius had an issue with poor accuracy and the replacement optical board fixed it (looks like it had an additional capacitor)
https://www.aussiearcade.com/showth...n2-PCB-to-Original-Namco-Arcade-Gun-mod/page6

https://imgur.com/FeUk3FK
 
That sounds right. I have been digging into this issue a little further and trying to compare the various boards for differences. It's not easy because some of my guns have the IO and optics boards in one while others use seperate boards.

But... as far as I can tell, there are two main differences on the optics board and one on the solenoid. Specifically, the Namco boards have a capacitor on two of the legs of the optic sensor and they have a third (ground) leg while other guns use just two legs.

On the solenoids, real arcade guns sometimes have copper shielding which I assume prevents emi.

I bought some capacitors so I'll give that a try first.

Right now these guns are for use on a PS2 and Dreamcast but learning how to fix the problem for one should be useful for all platforms.
 
I can now confirm that adding a capacitor between the two sensor legs in a light gun does not fix accuracy issues. It made the problem far worse so I either don't understand where the cap is meant to go or the info was wrong.
 
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