Sega Genesis Konami Justifiers not working

[TmEE]

NES does not allow controller ports to generate interrupts... so when you press the trigger, the game whitens up the screen, and sees if gun reacts to it then it leaves the object you shoot black, and when gun sees nothing then the game knows you hit the target. This is just one method, and this method is not fooled by the lightbulb trick.
SMS and MD allow controller port to generate in interrupt and the VDP provides pixel coordinates also and this makes the gun stuff more flexible.
All the light sense based guns work exactly the same... if they see light they react by pulling up/down a signal... its up to the HW or software to deal with the signal.

[kool kitty89]

Wait, does that mean the Zapper can work on digital (LCD/Plasma) displays?

[goldenband]

OK, I'm having a similar problem. I bought Lethal Enforcers CD two months ago, and I haven't been able to get this Justifier to register onscreen at all. Exact same results as described above: when I pull the trigger, the screen flashes, but it never registers a hit.

I've tried two different CRTs on two different occasions, and it doesn't work on either of them. Cranked the brightness, contrast, but no luck. Meanwhile, my SMS Light Phaser works perfectly on both TVs.

Finally I just tried pointing the Justifier at a nearby lightbulb, point-blank, and pulling the trigger while on the Lethal Enforcers gun calibration screen. Again, nothing: just a flash on the screen, but no sign of a hit. (I should note that the lightbulb is a CFL, not incandescent, but I don't expect that'd make a difference in this case.)

The weird thing is that the seller says he tested it before he sent me the gun, and I 100% believe him. So what could the problem be? Is it worth taking the gun apart and checking it out? I don't have any soldering experience, so replacing the phototransistor is probably beyond me...

EDIT: I just opened up the gun and noticed that of the three wires coming from the phototransistor board, two have been cut. The blue one is intact, but the yellow and green wires have been cut close to the main board, so that there's about 6" of each wire coming from the phototransistor board, and 1" coming from the main board.

I'd reconnect them, but the cut is very clean which makes me wonder whether the gun was manufactured this way...?

EDIT #2: Well, I stripped and reconnected the wires, and now the Justifier works. Who knows how that happened, but at least it's fixed. The yellow wire only barely reached its counterpart, and they're just held together with electrical tape, but hopefully it'll last for now.