First Time Slot Machine Repair

[GSlot]

Hello everyone.  I've been browsing this forum for a little insight on a slot machine I'm trying to repair.  I'm doing the repair for a friend that trusted me with his slot.


The machine is a Universal Tropicana.  I cannot see a model number anywhere.  There are several stickers inside that are all in Japanese or Chinese.  There is a metal serial number plate at the top of the machine.  It's in Japanese or Chinese too.  There are a couple of numbers.  561.  0285-25-5521~4.  Then stamped in the plate are: 8529 and 100434.


I was able to get the machine to power up after replacing the main power supply and MPU board capacitors, and cleaning and deoxidizing all of the contacts and connectors.  I can insert coins and get a chime out of the speaker.  If I insert more coins I get more chimes.  When I pull the handle or push the button, the coin lights go out, and some of the face plate lights turn off until the handle is released.  The opto sensor on the handle apparently works as far as the lights go.  There is no motion, not even a sound, from the reel motors.  The machine does not appear to "reset" after the handle pull.  Like you would expect if it were playing.  The Game Over light does not start blinking as it does when the machine is first turned on.


I do not have a service manual or schematics so I don't really know what to look for in terms of what controls the reel motors, or makes the machine reset after the handle pull.  There appear to be two power supplies in the main power supply unit.  One with a single power transistor and four large capacitors.  The other is hardwired to the fluorescent bulbs.  The fluorescent bulb power supply is super hot, but it does have an aluminum heat sink that wraps all the way around the power supply board.  That amount of heat might be normal, but I do not know.


The MPU board must be working to an extent because it senses the inserted coins and plays the coin drop sound.  It also adds to the coin counter in the back of the machine.  And, the number of coins inserted lights increment as more coins are inserted.  My suspicion is that maybe one or more power transistors on the MPU board are bad, and that they might control the power to the reel motors.  As far as not resetting when the handle is pulled, does the MPU sense how far the reels turned in order to reset properly making the Game Over light blink again?

[UNIMAN]

The Tropicana's are older than the 8116 machines and I have never worked on one nor have I ever seen a manual. Most have skill stop buttons, does this one have stop buttons? Does it have a spin button or only plays when handle is pulled?


The 8116 Uni handles have three optics on the handle. YOURS MAY BE DIFFERENT  When the first coin is inserted a solenoid (making a loud click) releases the handle and the handle release optic sees that. Then the handle is pulled to the full stroke down and the Downstroke optic sees that, when the handle is released and allowed to go back up, the Handle return optic sees that change. Believe all three need to be working for the reels to spin.


Look to see if there are more optics on the handle.

[GSlot]

This machine has one spin button on the front panel and the handle only has one optic.  The optic is working.  I can see the status LED on the outside of the optic housing.  That turns off when the handle is pulled far enough down.


I have to go to my daughter's graduation on the other side of the state today, so I will not be able to respond to any posts until tomorrow.  I'll be happy to take some photos and post them too.

[UNIMAN]

Ok, you have a spin button so either handle or button can initiate a spin. Doesn't look like a handle problem.


You said the coin lights go out and some of the face plate lights go out when spin button is pushed or handle is pulled. Those lights should be 24vDC as are the reel motors.
Could be there is a short pulling down the 24vDC when reels are initiated. (power supply could be weak too) I would try process of elimination by unwiring/unconnecting all three reels and pushing the spin button or pull the handle. If, with reels unconnected, the coin/faceplate lights stay on then one or more reels could be the problem. Connect one reel at a time and repeat to find bad reel motor. Looks like something pulling down the 24vDC.


Graduation congrats to your daughter!!

[GSlot]

I disconnected the connectors to all three motors.  When I powered on, I could press the credit button inside the coin slot to get up to three credits.  It chimes with each push of the credit button.  When I pushed the credit button once, the PULL HANDLE light came on.  I pulled the handle and the PULL HANDLE light turns off.  All other lights stay the same - on.  The GAME OVER light does not light again.  It only comes on when the machine is first powered on.  Pressing the credit button does not do anything after that pull.  No sound nor credit lights.  This is with all of the reel motors disconnected.  I did this test again, with the main wiring harness disconnected from the reel PCB.


There is a seven segment display in the upper cabinet.  I don't know if that is a credit counter.  But it has never come on.  I'm not really sure what to check next.

[UNIMAN]

Well, if the lights didn't go out with reels unplugged, I would try one reel at a time. Plug one in and try it. Each one until you find which one kills the lights. And see if any spin.

[UNIMAN]

Again, I know nothing about the Tropicana's. I see where you said you don't have a credit light and you cannot get credits pressing the credit button, and no sound after pulling the handle. And you have a 7-segment display above the reels that doesn't light.
I'm guessing that unlit 7-segment display would show errors or error codes.
On the Universals I work with a disconnected reel or reels would give an error code and requires a reset. Is there a reset button on this machine? If there is, try pushing it after the reel disconnected test and see if machine is ready to play again.

[GSlot]

I did some more testing.  There is no different response from the machine if I disconnect the reels.  Everything reacts the same.  When I press the credit button inside the door, on the coin receptacle, I get one chime.  If I press two more times, I get two more chimes.  The fourth press, makes the credit light on the front panel light.  When I pull the handle, the credit light turns off.  Nothing else happens.  When I press the credit button after a handle pull, nothing happens.  I have to turn the machine off and back on to make it respond to credits.


I do not see a reset button anywhere.  All the way in the back right side is a coin counter, or credit counter.  There is a toggle switch on that box.  The toggle switch is spring loaded, so when it's pressed down, it goes back up.  This button doesn't do anything, unless, it's held down when the power is turned on.  When you do that it appears to go into some sort of test mode.  Any button presses make all of the lights, except the seven-segment display to turn on.  Releasing the button, which ever button you pressed, makes the lights turn off.  This can be repeated.  However, I could not find a combination of button presses to get into a "test" mode.  The only thing this mode appears to do is test the lights.


The only way to reset, that I have seen so far, is power off and back on.


I replaced all of the capacitors on the power supply and CPU board.  The machine was pretty dirty and looked like it had a lot of use.  The main power supply caps were swollen which is why I did the recap.