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• Slot Machine Wheel Tilt Error
• Slot Machine Tilt Error

Introduction.
First I would like to state that in regards Sigma slot machines, no one seems to be archiving any informationon these. It really too bad as these are *great* slot machines forthe home. Excellent graphics and game play with good bonus games.And they are fairly inexpensive compared to Williams and IGT models,yet have all the same features (if not more).

Sigma was bought by Mikohn around 2003, and then was sold toMultimedia Gamingin 2005, where the UV1700 was shelved. So most Sigma uv1700 video slots were made between 1999 and 2003.Because of the Mikohn buy, the uv1700 history is a bit hard to track,hence this web page. Though most pinball people hate slotmachines, I find them interesting (especially given their reasonable price.)I mean compare a Sigma uv1700 video slot to the industry leader (at the time),the Williams 550 video slot. They are very similar, maybe the Sigma is evensuperior (better animation, easier to work on). But the Sigma is 1/4 the price of a Williams 550 slot machine.For 'bang per buck' the Sigma UV1700 is hard to beat.

The Sigma 1700 slots are generally pre-TITO machines (TITO is 'ticket in, ticket out'). Meaning they take coins and paper money, and have a hopper to payout coins. Unfortunately Sigma was the innovator of coin-less slots, and this showed upin the trail end Sigma uv1700 slot machines (TITO with ticket printer and no hopper). Generally speaking, most new slotsafter 2003 are TITO and don't handle coins, only paper money and tickets.So it makes sense that some of the newer Sigma 1700 models didn't have hoppers. The first coinless slot machines to be installed in a major casino was theSigma Derby horse racing machine. But to me TITO machines are not a good home slot machine, and is not really the type of slot I would want in my home gameroom.(Though do I really want to 'cash out' 800 credits in nickels at home?Heck no, but maybe it's just the idea that I could do that.)

Sigma Gaming Brief History.
Sigma Gaming was actually founded in Tokyo (Japan) back in 1984. They were the first non-U.S. slot makerto gain Nevada Gaming Commision certification. They did relocate to Las Vegas in 1996, but the Japanese touch remained. Sigma was known for technical innovations,and Sigma aggressively marketed their slot machines and poker machines. This spurred competition, and IGT (International Gaming Technologies)decided to take Sigma to court over copyrights.(Sound familiar? See the Williams slot history fordetails.) In 1989, IGT claimed the Japanese Sigma Gaming had been stealing patented game designs from IGT. This was eventually settled out of court.Sigma is one of only a few manufacturers to hold an unrestricted license to use the Telnaes technology (which IGT holds the patent) that allows for virtual reels and unlimited odds. (Spinning reel only, does not applyto video slots, see Williams slots for moreinfo on this.) The Telnaes technology enables Sigma to offer the ability to provide high-end payouts and progressive jackpots without limitations.

In 1990 Sigma came out with the first 'slot top' (sit down) slot machines.Though not a good home slot machine format due to size, these were very popular inthe casinos (and still are today). Players loved the comfort of sittingdown to play. In 1991 they were honored with the State of Nevada Governor's Industry Appreciation Award for its continued contribution to Nevada's growth. Again in 1996 Sigma received the award again.

Sigma was also the first company to embed a dollar bill validator into their slot machines, which made playing a Sigma slot one-stop shopping. To the casinos it was not about comfort, butto keep players at one machine for a longer period of time. There would be no breaks to go sit down, and no need to run to the cash machine. The ideas worked, and soon IGT was copying Sigma Games.Sigma wanted to build slot machines which were user-friendly. They made their slots easy to use and more comfortable to play, hoping this would lead to player loyalty.

Sigma also released the firstred, white & blue-themed game (Patriot), and a patented locking cashbox extractor. The cashbox extractor featured a design licensed to and utilized by two other leading slot machine manufacturers (Bally and Wms), and was offered by JCM.

Sigma Gaming made other slot play innovations too. Though they didn't invent it, early on they were part of the trend to increase the playusing big credit bonuses. If you payed the full price to play (all the creditsthe game would except for one spin, which in some cases was up to 50 credits), the bonus structure made it worth your while. This is standard nowadays.

Around 1999 Sigma jumped on the video slot machine bandwagon with theSigma uv1700 video slot. The video slot was a marketlargely developed by Williams (Wms), and one that Wms excelled. Sigma met andI would say surpassed Wms with the uv1700. Animation is more refined onthe Sigma, and the machines are far easier to repair.

As for repairs, Sigma slots were easier for casinos to repair (and us too, since these are now in our homes!)For example the UV1700 Sigma slot machines shown on this page arebased on 300 mHz Cyrix/Pentium PC computer hardware, using standard 168 pin 256meg SDRam DIMM pc100 or pc133memory sticks and CD ROM drives. But the PC board isa bit different than those seen in your home computer.Instead of a board with a zillion connectors, the Sigma 1700 slot uses a DPX-80 board from Densitron Technologies andGamingboads.com, using a single 'ConnectBus'connector. This board eliminates the need to plug and unplug different connectors for power, HDD, FDD, monitor, etc. That is, all power, I/O, and interface signals are routed to a single ConnectBus connector. This makes the board literially 'plug and play', allowing Casinosto easily swap a motherboard to fix a machine. Everything is on one board,so it's pretty painless. (Though a hardware 'clear' is still requiredthough to change a game.)

Slot Machine Wheel Tilt Error

Unfortunately this all came to an end in 2005, as Sigma (called Mikohn since 2003) was bought by Progressive Gaming International (PGI). At that time PGI stoppedselling the Simga UV1700, andnothing further has come of the Sigma 1700 platform.

The guts of a Sigma 1700. Looks like a regular PC eh?
That's because it pretty much is a regular PC.

Sigma uv1700 and uv1900 (sit-down) Slot Machine Hardware.
The motherboard used in Sigma 1700 slots was a 'ConnectBus' Densitron Technologies DPX-80 board,with a single connector for all power and hardware. This allowed a techto replace a motherboard in about 10 seconds.The processor is a Cyrix MII-333GP (333mHz clock speed with a 83mHz bus 3.0x, 2.9 volts.)Memory includes two SIMM 72pin EDO sockets (not used) and one DIMM socket (SDRam 168 pin 256megpc-100 or pc-133, depending on how old the DPX-80 motherboard may be.)Interestingly many games can run with 64meg or 128meg of RAM (thoughKiss requires the full 384meg, Garfield runs at 288meg or above.)The Densitron Technologies DPX-80 board supports up to 450mHz clock speed using a socket-7 compliant processor.Design features include PCI accelerated Fast Ethernet LAN controller, PCI 64-bit accelerated LCD/CRT graphics controller with digital LVDS/PaneLink interface, PCI Ultra DMA/33 EIDE controller, expansion for PCI/ISA buses, analog video input port, touchscreen controller capable, DiskOnChip flash disk socket to 144 Mbytes, 16-bit stereo sound system, two USB, two parallel, four serial, MIDI, mouse, keyboard, and two floppy disk ports.

The Densitron Technologies DPX-80 as used in the Sigma 1700.
Shown is the board loaded with 256meg of DIMM pc133 RAM.

In 2002 Densitron Technologies introduced the DPX-91 motherboard, which is backwards compatible with their DPX-80 and DPX-81 ConnectBus motherboards.Though I've never seen this used in a Sigma uv1700 slot machine, there is a chance itmay work.

Sigma 1700 17' Touch Screen.
The really cool thing about the Sigma uv1700 is the 17' color touch screen.Great resolution and graphics, and a touch screen to boot. It's a nicefeature, especially given the price the Sigma 1700 sells at. The touchscreen is nicely implemented into the game play too (some games use itmore than others.)

The coin door opened on a Sigma 1700. A pretty tight design!

Sigma RAM.
All Sigma uv1700 games have a single DIMM ram socket,usually fitted with PC133 256meg 168 pin SDram. This is the maximumRAM size that will fit in this socket (though some older games may onlyhave a 128meg SDRam card.) I have found some uv1700 boardsthat want PC100 SDram, and won't boot with PC133 (or vice versa.) Either the game will lock up at boot (no power-on 'beep'), orit will beep on and off constantly (signifying a RAM issue.) Reseatingthe SDRam or replacing usually fixes this problem.Note that Garfield requires pc133 DIMM RAM withSerial Presence Detect (SPD) aka Low Density. This is denoted by a second notch cut into the ram on the sides (the second notch is abovethe stock notch seen on 'regular' RAM.)

There are also twoSIMM 72 pin EDO RAM sockets, which will hold 64meg each, andthat are not utilized. Only games I am aware of which require more than 256meg of RAM isKiss and Garfield. These games require the DIMM 256meg SDramplus the two SIMM sockets to have 64meg each, for a totalof 384meg (actually Garfield will run at 320meg, but Kiss requiresthe full 384meg.) Also some brands of PC133 DIMM memory won'taddress the additional SIMM sockets - The DIMM memory must haveSerial Presence Detect (SPD). So in the case of Garfield and Kissyou must have the 'right' 256meg DIMM SDram memory with SPD, in addition to the twoEDO 64meg 72 pin SIMM memories.

Finally you can run most Sigma games with just the two EDO SIMM memories installed (128meg), andno DIMM memory. So if you can't get a board to boot right with the DIMM SDram,sometimes trying the SIMM memory can get a board working.

Sigma uv1700 board with both DIMM and SIMM memory installed for Kiss/Garfield.

Sigma 1700 Parts and Repair.
Of all the slot machines I've worked on (and I've worked ona bunch!), the Sigma 1700 is probably the easiest to repair.It's more like a PC computer than a slot machine. There'sjust one board (the 'motherboard'), which is basically a PCmotherboard. I've yet to need to repair a power supply.The mother board uses PC-100 or PC-133 stick 256meg memory (available at the localcomputer store), and a standard CD or DVD drive to read the CDs.The CDs themselves are copyable with say Nero, which means backupsare a breeze (and I do suggest you keep a backup around.)Memory is kept intact with two standard drug store coin batteries(CR4025).

The only thing I don't like about this platform is thetime it takes for the game to boot. Because it's a PC based system,it goes through a memory test at power up (which can be abortedif a keyboard is attached), and the time it takes to check the CD rom.The game reads the entire CD rom and does a checksum against the valuestored in the motherboard's PLCC u52 game chip. If these don't match the gameaborts. This was done so someone doesn't 'hack' the CD rom (easy to do!),changing the game code. So total boot time is probablya minute or three, where most other slot machines boot in 10-20 seconds.

Coin and Dollar Bill Validators.
The coin hardware (if the Sigma has it, not all do) can utilizestwo different coin entry systems.An IDX coin comparitor (programmed for the appropriate coin) canbe used, assuming it has the correct 'personality plug'. Also aMicro Comparitor MC-40 (cmi# 66460089) can also be used (12vdc,InHhi,PR7).In either case both of these systems have the coin-in optics built intothe comparitor.

Micro Comparitor label showing the proper part number.
This is important as there are many different models of Micro Comparitors.

The bill valiator used is JCM's WBA-13 model, which is a reallynice dollar bill acceptor system. If using version 3.75 of the software(it has a 4meg 274001 EPROM built into the WBA transport), it willaccept all colored U.S. money with no problems. Note the head is thesame on a WBA12 and WBA13, but the transport is different.

Sigma 1700 Game Software.
Software (game changes) for a Sigma uv1700 is pretty easy too. There is a single smallPLCC (square) 32 pin 4meg game EPROM chip on the DPX-80 board at U52. And this chip must have a matching game CD ROM. A Dallas 'All Clear' chip is run first at U51 (replacing theboard's 'boot' chip), clearing the memory.Then the boot chip (u51) is replaced, and with the newPLCC game chip (U52) and game CD ROM are installed, the game should run.Upon bootup, the CD ROM is fully read and its checksum compared to the checksumstore on the PLCC game chip (u52). If the checksums don't match, the game gives an error and does not proceed.

Interestingly the 4meg PLCC game chip is pretty much blank.It only contains the checksum of its matching game CD ROM, and some general game parameters (like whether it's a nickel or quarter game, etc.) About 200 bytes of actual info is on the game PLCC U52 chip, and the rest of the chip is blank with '00' stored at each byte. So the PLCC chip onthe motherboard is really only used to verify the CD ROM (which is whereall the game software resides.) Because state regulators don't want tomake game swaps too easy for casinos, the PLCC chip's stored checksumis used so no one can put a 'hacked' CD ROM in the Sigma.

The PLCC chips (Bios, BdBoot, Game chip) and the two coin batteries.
The socketed 'Disk on Chip' provides a solidstate disc work area for the operating system.

Sigma 1700 Progressive Slots.
Sigma made a couple games that were progressive only. That is,they won't run standalone without a networked computer behind them.This is unfortunate as the two progressive games (Lava and Easy Riches)look like good games. (I can load the games and add credits, but theywon't spin because of the lack of a progressive network to support them.)If anyone knows how to get around this, please contact me.

What's the 'Best' Sigma 1700 Game?
I get asked a lot, 'I want a Sigma slot machine, but which is the best onefor my home?' That's a hard question to answer, as it's like asking, 'which flavorof ice cream do you like the best?' Actually I like all the Sigma 1700 games,but Battleship is my favorite.

Sigma Boot Codes.
There's a two digit LED on the corner of the CPU board.I don't have the error code definitions, but I have managedto write down what a proper uv1700 does upon bootup:

• c1 c6 c3 - real fast upon initial power on.
• 06 0d 0e 31 - then game beeps that familar PC boot sound.
• 31 - stays at this until memory test completes.
• 3d 6f 42 4e
• 52 60 62 ff - boot up complete, game should be running, stays at FF.

Sigma Power-On Constant Beeps.
A common boot up error at power on is constant beeping from the speaker,and a C6 error on the LED. This happens when the SDRAM memory stick is bad. Sometimes a simple power off, reseat the memory stick, and power back on will fix this problem. But other times a new memory stick will be required (168 pin 256meg SDRam DIMM pc100 or pc133.) Look at the existing memory stick and see if it is pc100 or pc133 (it should be labeled), and get the correct variety. Using a pc100 memory stick in a board made for pc133 won't work. If the memory stick is unlabeled, best guess is to go with pc133 (which is the most common.)(Yes there are several different versions of the mother board, and the earlierversions use pc100.)

Sigma Game Numbers, Titles, Pictures.
Below is a list of all the Sigma uv1700 video slot machines I have found.The game numbers are important, as the game number on the u52 motherboardchip must match the game number on the CDrom. Note I have some u52 chipsbut no matching CDrom. If you have a cdrom for any of the game numbersI am missing, I would really appreciate hearing from you.

Here's a list of games I know are out there, but have not seen:

• Clue
• Trivial Pursuit (seems to require a network)
• Working Overtime
• Ten Hand Stud Poker
• Flying Aces
• Gold Island

Repair Tips for Reel Readers

How to test and what to look for when doing your own repairs

When one of these goes bad you may see an error that would be 4x or 7x where x indicates thereel position, i.e. a 43 error code would indicate the reel reader on the third reel.

What is described below is for testing the reel reader card using this home built tester. The tester provides both a 50 volt source or a 5 volt source (switch selectable).

After describing this procedure I will tell you how to test the cards with out having to have a 50 volt source.

I designed and built a tester to make troubleshooting easier. I test the card and all of the photo-transistors
first, then I split the two halves of the card, one for cleaning but also so that I can use a dental tool, poking
it into the tiny opening to push the photo-transistor or IR Emitter back up and out of the small square opening. The photo-transistor/Emitter should be at something close to a 45 degree angle.

Once the bad components are pushed out of the way, I use my soldering iron to melt the solder on both leads at the same time while grasping the upper portion of the optic. It comes off very easily. Once removed use solder wick to remove the excess solder. You want to do this so that when you put in the new device the leads will be nearly flat on the PC board.

Replace the defective components and quickly tack one side, allow the solder to cool and then solder the other side. Once the other side has cooled you can go back and firmly solder the lead that was previously tacked. Reassemble and then retest to make sure that the optics are working properly. Tapping the top of the card lightly with the handle of a screw driver will show any intermittent connections.

The one question that may come up is what constitutes a bad device. Since the reader cards supply signals to TTL logic devices then we can use standard logic levels of 2.0 volts as a high and .8 volts as a low. When measuring the output of the photo transistor, if the voltage is less than 2.0 volts, while unblocked or higher than 0.8 volts when blocked then that photo-transistor (or emitter) is defective.

In the cards that I have repaired I typically see voltages of greater than 4 volts unblocked and .01 volts blocked for the 50 volt reader cards, 5 volt reader cards the unblocked voltage is 3.14 and the blocked voltage 0.2.
Test all of the emitters and photo-transistors first, the replace all defective ones. I make it a habit to clean the bulbs with alcohol on the 50 volt cards so that as much light as possible gets to the photo-transistor.

Testing reel readers without having a 50 volt source.

The 50 volt supply is only used to power the incandescent bulbs. They are in series along with the 470 ohm resistor. Each bulb requires 5 volts to operate properly.

You need a few basic items, a Volt/Ohm meter (DVM) , a 47K resistor, a light source (flashlight) and some clip leads and a 5 volt DC power supply

Split the cards by removing the 2 screws and lay the small card off to the side

If you lay the card flat on its back with the mounting bracket to the left then the pins at the bottom will number 1 through 16 from right to left
Measure the resistance between pin 16 and 14, Pin 16 is Vcc and 14 is Ground you should have a reading a bit above 500 ohms, indicating that the 470 ohm 2 W resistor and all of the bulbs are OK. If not in this range then you will have to remove the tape covering the backs of the bulbs and then measure resistance across each bulb individually. Remember the bulbs are wired in series like the old Christmas tree light strings.

Assuming that the bulbs and resistor are OK. Attach the ground lead of the volt meter and one end of the resistor to pin 14 (pairs 13/14)
of the card. Connect the other end of the resistor and the positive lead of the volt meter to pin 11.

Now using the 5 volt supply, apply 5 volts to pin 1 of the card and read the voltage, shine the light into the small (tiny) hole that is for Q1, voltage should be some where around 4.7 volts with the light on and some where less than 0.2 volts with the light off. Just keep in mind that ambient light might cause the light off reading to be higher. The acceptable voltage ranges need to be within the acceptable ranges used in ‘Logic” circuits so a logic high you need 2 volts or more and a logic low 0.8 volts or less.

You may find that if you have these readings, a Q-tip dipped into alcohol can be used to clean the top of the photo-transistor by pushing the Q-tip into the hole and then twisting the Q-tip. I routinely clean these as well as to clean the bulbs.

Repeat this process for each of the following pins 1, 3, 5, 7, 9

Other than pin 11, all of the other pins are in pairs

Pins 1 & 2 Collector of Q1
Pins 3 & 4 Collector of Q2
Pins 5 & 6 Collector of Q3
Pins 7 & 8 Collector of Q4
Pins 9 & 10 Collector of Q5

Pin 11, Common emitter
Pin 12 Missing (pin is cut off)

Pins 13 & 14 Ground
Pins 15 & 16 Vcc
This process is not nearly as quick or accurate as using the tester but should allow you to test each of the cards.

The 5 volt card testing process is not much different other than it is not necessary to split the cards and you need a 3K resistor instead of a 47K resistor.

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Apply the 5 volts across pins 16 and 14 and then measure the voltage on the associated
pin pairs.
In this case the 3K resistor attached to pin 14 and pin 11 biases another transistor’s base (Q6), pulling it low so that it will turn on the IR Emitters. Remember to block the light for each IR emitter to see the photo-transistor transition to a low state.

Testing results for the 5 volt cards readers you will not read anywhere near 4.7 volts, they will be closer 3.0 volts for a high and about 0.2 volts for a low

Repair Tips for Power Supply

I have noticed that the schematic for the Bally E1000/E2000 power supplies list expected voltages, but, what does that mean?

I have a couple of these power supplies so I decided to do some testing to see what voltages were obtained under certain circumstances.

If you apply 12 VAC across pins 1 and 10 of the board J1 connector,you should be able to measure the voltages on the test points (+UR, ZC and 5V)

These voltage readings are based on a supply that has no load (nothing else connected)

UR = 15.96 VDC
ZC = 10.07 VDC
5v = 5.0 4VDC

Slot Machine Tilt Error

One might think something is wrong because both UR and ZC are higher than the schematic states. However with no current we would expect to find the voltages higher, what matters is the voltage under load conditions.

The LM340-T5 Regulator has a maximum current output of 1 amp so using ohms law we know the voltage is 5 volts and the current is 1 Amp, Resistance can be calculated using the formula R=V/I (R=5/1) so R=5Ω, Now that we know what to use, we can figure out the wattage, this is rather simple, Watts = Amps x Volts so in this case we have 5 volts, 1 Amp so need 5 Watts. For testing I use a couple of 5Ω 5W resistors , actually, I use 20 Watt resistors to keep from burning my fingers. Anything smaller than 5W will burn and smoke is bad. The load resistors are placed across pins 13 and 20 of the J1 connector

To test the power supply drawing .5 amps we place 2, 5Ω resistors in series for a total of 10 Ω. With a 10 Ω load, drawing .5 amps these readings are fairly typical of what you should expect to see

UR = 12.16 VDC
ZC= 8.83 VDC
5v = 5.01 VDC

The final test is to test at full load, drawing 1 amp of current by removing one of the 5 ohm resistors so that only 5 ohms appears across pins 13 and 20 of J1, the readings you should expect to see would be.

UR = 7.57 VDC
ZC= 9.6 VDC
5v = 4.98 VDC

It would appear that the voltages shown on the schematic are voltages when the power
supply is measured with a full load.

I also recommend that when repairing these power supplies to remove the heat sinks from the bridge rectifier (BR1) and the 5 volt regulator (Q1). Clean off the old thermal heat sink compound and add new compound so that the heat transfer is more even. This will allow for maximum cooling.

The minimum voltage to expect from the LM340-T5 is 4.75 volts, if less than this then it is better to spend a couple of dollars and replace it.

Sometimes you will find that you have no voltage. In this case you want to check the 4 diodes and if the voltage seems to be half of what you expect then check the solder connections on the bottom side of the diodes. These will become bad because of heat. Other causes of no voltage is an open diode in the Bridge Rectifier (BR1).

I would recommend to anyone doing any type of repair work to invest in an ESR Meter. ESR means Equivalent Series Resistance and a high ESR can have adverse actions to your circuit. I have had several of these power supplies where despite changing the diodes, bridge rectifier and voltage regulator the output voltage was still below the regulators specified voltage of 4.75 volts @1 amp. These problems were resolved using my ESR meter and the discovery of the large 11,000 ufd capacitor having a high ESR value.

Can’t run Tests

I have seen many complaints of not being able to run the tests or clear errors on these E Series machines. If you have a light tower the WHITE light should be illuminated before the tests or resets can be done. This does not mean that a burnt out bulb will prevent this but only serves as a quick indication that you should be able to run tests or clear error codes. If you find that you are unable to run the tests or reset the machine, check the cherry switch behind the door hinges. If this switch goes bad it will signal the MPU board that the door is closed. Many owners of these E machines will bypass the door switch however the cherry switch must be operational

RAM Tester

Since many of the problems with the E Series slot machine are related to RAM failures I thought it would be a good idea to have one hanging around in my shop. I searched the web and located a guy that had developed a tester for testing the 6264 RAM chips. I sent him an email asking if this might be easily converted to test the 5101 RAM chip used in the Bally E Series slot machines and a large number of Bally Pinball machines. As it turned out he did not have a problem in making this modification as an ‘Engineering Change’ for me. My tester only tests the 5101 RAM chips, but NeoLoch Sales has since altered the design so that it will now test 5101, 6116, 21C14 and 9114 RAM Chips. It also will run on a 5, 12 volt power supplies or from a 9 volt battery.

For further information please visit his website NeoLoc the page will open in a new window. This tester is now obsolete and has been replaced by a newer more versatile version

If you have some electronic design work that you need to get done contact David, he is easy to work with and offers reasonable prices.