Part/Board Terminology

[61Wally]

Can Someone please tell me What the Correct Name is for this board and its purpose. I’m guessing Maybe something in the voltage regulating department? Thank You ALL.

[Pitts256]

That is the "TOWER 4-P.C." relay control board. The main logic board uses it to control a set of three solid state relays that control 24vac to the tower (aka candle) Door Open, Call Attendant and Jackpot Lamps as well as a sub board for the Pull Handle Unlock Coil.

[61Wally]

Quite a bit of items, If that piece has taken a dump could that be the reason Why I’ve lost everything? Display, I can’t reset anything. The Only thing I get is the handle solenoid starts chattering after the machine has been on for a few minutes. I tested All the voltage outputs except for pin #8,(I didn’t understand that one) and they were correct. One moment it was working great, turned it off next day back on and a bright brick with fluorescent lights is All that works. I’m lost on these Universal machines. Any suggestions/Thoughts?

[Pitts256]

A tower board intermittent short to ground could cause the tower lights to flicker or the door handle solenoid to chatter. Worse case it takes out a fuse. Optoisolator chips protect the main processor board.

CN4 pin 8 is the 9.5vac to the main processor board. Loss of 9.5vac will shut down the main processor board.

Did you power up the machine while holding down the "ALL RESET" button on the main processor board? The RAM may be corrupt.

I'm working on an 8116 now that had similar issues; LEDs and lamps flashing and solenoids chattering. The main board battery was bad, acid leaked on the board and the corrosion caused some traces-solder joints to open or short to ground. The memory decoder chip was also effected and must be replaced.

[61Wally]

To make sure that I’m correct, This button is the one to the left of the hopper on the MPU board,(There’s a little slide plate on the cover and inside  there’s a small black monetary push button. My understanding if I’m doing it correctly, Is to hold it down 3-4 seconds after I turn the machine on. Once held down it makes a noise and then I can let up and proceed forward. This machine had a dead battery as well. I cut out the resistor that’s part of the charging circuit. I replaced it with a new lithium 3.6 volt battery and it worked great for a short period of time then turned it back on and nothing, except for that chattering solenoid after a few minutes. I’ just installed everything back in it and I’m going to check the voltages at the pins that were listed to test. I will post shortly the results.

[61Wally]

When I saw the post about what to test, I didn’t understand for sure about pin #8 test procedure. It states that it should be 9.5 VAC. My question is Testing pin #8 is the other test lead go to pin#7(ground) or another pin? That was my Only confusion when I went down the list.

[Pitts256]

Yes, the push button on the main CPU board. Hold the button down, power up and continue to hold the button down for 2-3 seconds after powering up. You'll typically hear the door coin divertor solenoid pull in, the pull handle solenoid may pull in and the sound amp power up.

Loss of the battery voltage to the RAM shouldn't prevent the board from starting up. Loss of VCC (+5vdc) to pin 24 of the Ram chip will though.

Since the resistor R27 was removed when the board is powered up the voltage on the battery should remain the same, about 3-3.6 volts, if there's more than 3.6 volts then the switching diode D5 could be shorted.

The 9.5vac pin 8 will be close to 5vac when measured to the DC ground pin 7. To get the actual 9.5vac you'd have to measure at the power supply transformer taps. If there's 5vac at pin 8 you're good.

[61Wally]

I don’t know if I tested Pin#8 correctly or Not?
I used Pin#7 as ground and had strange results. Testing It showed 4.42VDC & 5.2VAC

[61Wally]

What You just wrote is exactly what happened after I changed the battery. I played it to the point of building up 500 credits and when it would hit a winner the coins would dispense out into the tray, I was at the credit limit. I quit for the night, next day came back and everything was dead.
Not to change subjects here but what position does the hopper switch need to be in?

[Pitts256]

The switch on the hopper is for the type of photo eye installed. Here's the info:

"Optic Switch - The high-speed hopper is adaptable for use with either gray or black
TTL optic systems. For use with the gray optic system, the switch (located on the
relay board) must be in the position nearest the 16-Pin connector. When used in a
black optic system, the switch must be in the position away from the connector."

[61Wally]

OK Sounds Great except that went So far over My head I can’t even imagine catching it. I’m Not familiar with Universal machines at All, This is my 2nd one I’ve seen, trying to help a friend out who wants it fixed, family member passed and he has it. By looking at the pictures can You tell me what position I should use, Also how do I find the model #?

[Pitts256]

The hopper switch is typically "locked" in the correct position. Looking from the frontside the switch (by the Molex plug) is in the right position for the black optical switch and left for the gray.

[61Wally]

Thank You, Learning the terminology is a big part of understanding these concepts.