Konami Lethal Enforcers

Lethal Enforcers is a fun game.. in case you don't know it, this shooting game has 2 light-guns and you shoot terrorists appearing on the screen. There are several levels, and depending on how good you do, you increase in rank as police officer.

I had this acrade game for about a year. Then I really got tired of it. On free play with unlimited credits, it takes about an hour to finish the game completely (and you'll feel your arms from holding them up all the time).
However this arcade game has several difficulty settings, and set to 'street mode' (opposite to arcade mode) you can choose at which of the 5 levels you start, so there are some differences to gameplay. But there are no random parts in the game, each time you play it, it's identical to the previous time.
In the end I usually played the target practice mode most. In this you have to shoot targets that show on screen, and are ranked on speed and accuracy. But still the Lethal Enforcers arcade machine became boring and took up just too much space.. So when we needed some space this game had to go..

Lethal Enforcers is a violent game, you shoot all the time at people. But it's fun.. And this really is game which did very well in the arcades.. Ok there are light-guns now also available for Playstation and X-Box but it's impressive to play it on a real big cabinet.

The cabinet is very big.. it's not that this game uses an extremely large monitor, but to give the player an impression of depth it uses a mirror. The screen is actually horizontal at the bottom of the cabinet.

Tech: how to test and repair Konami light guns

When I got this Lethal Enforcers game, none of the guns were working.
The left gun didn't do anything at all, and the right one flashed the screen but the game didn't register a hit. As these optical guns are quite expensive and ordering from the USA would take some time, I tried to repair them first..

A small explanation about how these guns work, in case you don't know.
When you pull the trigger, the game quickly draws a white screen, pixel by pixel (or block by block ?).
The optical sensor inside the gun detects this white screen, and sends this signal back to the game. The game knows which part of the screen it was drawing white at that moment and registers a hit in that position. If you're playing you don't really notice this, but when you look at the screen while someone else is playing, the white flash everytime someone pulls the trigger can be noticed very well.

So regular troubleshooting goes like this:

• If nothing happens when you pull trigger : check wires, maybe trigger switch bad.
• White screen flashes but no hit is registered: problem with the opto. Check wires, maybe a bad opto, also clean the lens in front of the gun !
• Btw first clean the game !! As a small color difference is important, clean everything thorough. clean the front glass from the outside, then open the back of the game and clean everything inside: the mirror and the screen itself. The test menu will also show aid you to adjust color and brightness so the game will work. Also degauss the monitor, especially if you have trouble shooting targets in the corners of the screen.

Cleaning the monitor itself may sometimes be enough, as it will attract a lot of dirt because of the static electricity on it. If the arcade game hasn't been cleaned inside for years then a lot of dirt can be build up on the screen.

It isn't easy to open these lightguns. The two plastic halves are held together with special security screws, and I didn't find a tool for sale to open them.
So in the end I drilled the screws. This damaged the plastic case of my guns, but as the game is for home use, it doesn't really matter if they have some damage.
An official Sega distributor will have a special key to open and repair the guns.. but they'll probably charge you a lot to repair the games (or try to sell you a set of new lightguns).

Once the lightguns are open you see there's nothing complicated about them. I get the impression the lightguns are designed by Konami to break a lot, so they could earn a lot of money selling replacement parts to operators.. the wires used are really the smallest gauge possible !

Anyway, inside a gun you have 3 parts:

• a trigger
• a light sensor
• incoming wires

The wires come into the gun and connect to a weird assembly of round disks.
This is made so you can rotate the gun 360 degrees (or much more) whilst the incoming wire is held in place. Being able to rotate is done by connecting incoming wires to round disks, to which wipers connect.
Problems I noticed here:

• The wires coming inside the gun have a small connector on them which slides over a small pin. In one of my guns a wire had come loose here. So I think it is best to use a drop of solder to keep this small connector in place.
• The wipers are also very fragile and easily bent. Be very careful when you open the gun. If you're going to use the game in home use, it probably isn't necessary for the gun to be able to rotate unlimited around the incoming wire, so you could solder some extra wires here to make this connection better (or even just remove this disk thing completely if it's damaged, and connect incoming wires to wires used inside the gun ?). At least check this part for continuity.

Anyway, from here you have 4 wires: black (ground), red (+5vdc), yellow (optic sensor) and white (trigger).
With the gun open and still connected to the game (game started) you can measure all voltages (+5vdc should be present on red wire).

Check for broken wires. There aren't many wires in a gun, but the wire is very thin and easily breaks, so use your multimeter to check for continuity ! Be careful when you solder them.

Checking the trigger: just check for continuity between the two pins with a wire on them when you pull the trigger.

Checking the optical diode: three wires connect to this part: a black, red and yellow. First check there's +5vdc between black and red. You should also get +5vdc measured on the black and yellow wire. Now shine a flashlight into the opto led, and this +5v on the yellow wire should drop to (almost) 0. I've read on RGVAC there's also a capacitor on there too which often fails, so check and replace this too if necessary.

Finally measure continuity between wires inside the gun and the connector on the pcb.
That's it.. if the trigger works, and the voltage drops to 0 on the led, and there aren't broken wires, the gun should work. Have fun playing Lethal Enforcers !

Be careful when you re-assembly your gun as the small wires break easily !

Update

Here's an image of how a HAPP lightgun looks like internally. It's a bit more complicated as the Konami type described above, because this also has a coil that provides feedback, but the basic parts mentioned above can also be seen:

1. Lense
2. Optical receiver led
3. Trigger microswitch

The wires used are a bigger gauge and different colors. This type of lightgun does not have the rotating assembly like the Konami lightguns have.