There has been a lot of posts about the Monte Carlo game by Gottlieb but I couldn't find a club thread with everything in a central location. I guess it's time to start one!

Recently picked up a project game and want to get it going and restore it. I've fixed boards for these before but never played or owned one of these games. Looking forward to it since I've heard it plays well.

This thread can be a great place to share information about unique features like the roulette wheel, troubleshooting, sharing known issues, and anything specific to this game. I saw one other thread that new ramps are available. If you know of any other threads referencing this game please post them here.

Some questions for existing Monte Carlo owners past or present:

- How many balls is the game supposed to have for the main playfield? I believe 3 but would like to confirm.

- For the roulette wheel is that a standard size pinball or a smaller one?

- Mine was missing the screws for the round window and that window fell off when moving (It's all ok though). I've heard that it used 4 machine screws and two wood screws. Can someone confirm that and the sizes? I'd like to get the correct replacements.

- Probably will have more questions as I work on it!

Last night I had a little time to work on it. Had a large ball sitting in the roulette wheel. Two large balls and the small were sitting in the trough. That is why it wouldn’t start a game!

It needs a good cleaning, new rings, balls and shop job but should clean up well. Someone put grease on the flipper mechs so those will need to be totally disassembled and cleaned.

All six screws are missing on the routlette cover so I’ll see if I can get those at the hardware store.

Luckily the original Nicad didn’t leak on the MPU so no battery damage. Going to pull that off along with the 5101 and install NVRAM.

I also have a night moves with a similar supply. Changed out the adjustment pot on the power board with a precision 10-turn version. Will probably do the same on this game too.

The game plays solid and the displays are all ok. No reset issues. I still have another MPU that I fixed for a friend out of another Monte Carlo and tried that in there today. Same thing.

I get background music and some sounds. Plan on comparing to you tube videos to see what I’m not hearing. I know the coin drop sound is missing. Going to look over the schematics to follow the sound signals.

Does anyone have a spare topper for sale? It would be good to get reference photos of the topper on both the outside and inside showing the wiring.

What is the latest ROM version for Monte Carlo?

From the pinmame source it looks like their could be three versions for Monte Carlo. The plain 708, 708/1, and 708/2

Found a list of checksums on flippers.com and that appears to show there are two versions they know about. No checksums listed for the /2 ROMS.

Does anyone have the /2 version? Anyone know what was fixed or changed in each version?

I think I have everything sorted out! I had two MPU boards each running different versions and each one had a bad ROM. One had the original 708 version. That one had a PROM2 that the checksum didn’t match. Displaying the contents showed a lot of FF which is what the cells default to when erased. Replaced it and all ok with that board. The other board had version 708/1 and the chips verified ok in the programmer but failed the PROM check in the board. Just went with the free play set of 708/2 and that’s good too.

This is the 2nd time I’ve had an EPROM read ok in the programmer yet fail in the board.

I don't think "free play" is in the official 708/2 ROM's as those were tweaks done by flip projects.

Hopefully someone will have some old notes from Gottlieb that mention what was fixed in each version.

What is the issue with that shot? In the manual it shows that it lights up every 40 switch closures or at random depending on how a DIP switch is set.

Got it! Actually that probably wouldn't be all that bad to patch. Just need to isolate that part of the code to change the value added and the probably recalculate the ROM checksum. Unless the checksum is disabled in the free play versions.

My game is missing the topper. Normally I wouldn't worry about the topper but where I have it setup there is room to put it up and the topper for this is pretty cool the way it all lights up. I like to try and keep the games as complete as I can. Maybe there is another one out there.

Today is a good day! Just received my new ramp for Monte Carlo. I asked if it could be made in green right as Ramp-o-Matic was about to make a new batch. This will look really good on the game. Thicker than original and should hold up well.

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Awesome! Thanks for your work and posting what was done on the ROM's. I recently had to repair a couple MPU's for these machines and your existing freeplay code works great. Will need to make one of these sets to try.

I was just over visiting my son and had to play a quick game of Monte Carlo. The roulette wheel didn't seem to take that long. Only possible issue I see with adding that rubber piece is that it may skew the odds a bit as far as what number it ultimately lands in.

I haven't played it a lot but the game grows on you and I think it plays very well.

I made up a couple sets of the new Millions Mod ROM set and will see if I can get over to my machine in the next evening or to so I can try them out.

I made a couple sets too and will see if I can try one in my machine this evening.

the9gman Did you have an external power supply connected to your programmer? I have a few different EPROM programmers and it looks like you may be using a gq-4x4 programmer. For older chips the external power supply helps. While they may have verified when you programmed them have you pulled them back out and tried to verify them again? You may find they no longer verify and if you look at any bytes that no longer match the value will be higher as bits revert back to a 1 state which is like they are when blank.

Can you see if this is the case with your chips and they no longer match?

The gq-4x4 is a good programmer but even that can have a hard time with older EPROMS that really need longer write times or with chips that need a higher voltage. If you use EPROMS meant for a 12.5V programming voltage they are usually ok. I keep an older programmer around just to deal with older ROM's. Takes longer to program them but it does a good job.

Reason I mention this is I just used my gq-4x4 to program three sets of these ROM's and all verified after programming. One of the chips was a slightly older INTEL EPROM and when I went back to reread and verify that one chip no longer matched. One bit flipped. The others are all still ok. I did these on the gq-4x4 programmer since it was the most recent pickup. Any older chips will still be done on my old programmer.

The ST EPROM's should be ok. Can you try to re-verify the set you already made to see if they still verify?

This evening I set aside some time and tried them out but my machine started acting weird too and thought PROM 2 was missing. Pulled them back out and put in the /2 version of the Freeplay ROMs (thanks to the guys that made that awesome update) and the game ran perfectly again. I verified the new sets again with the programmer and they match what was downloaded. So it doesn't appear to be an issue with programming at the moment. Something may be corrupt in the binary images. I can make a fresh set anytime and will be glad to try again.

I’ll make a fresh set but use my old programmer. Your 708/2 free play version on the site works well and that’s what is running in my game now.

can one of you guys help me out? My Monte Carlo was missing the head bolts. I ordered a set from PBR along withe washers but it looks like the bolts they send are at least an 1" too long. IO'm not too concerned since I can use them on some other project but I still want to get the correct length.

If it isn't too much trouble can some one take a picture of the correct bolt and the length? It will also serve as a great reference on this thread for anyone else that may need them down the road.

Thanks in advance!

First, Let me say a giant thank you for all the work you've done on all the Gottlieb machines to upgrade and enhance them. Everyone can tell that you love these old machines and have a passion for improving them. You've made my Haunted House a better machine and I am very happy with the latest freeplay ROM set in my Monte Carlo.

It sounds like you have a really cool bench test setup. However that single PROM adapter you mention is a slight difference from what we use on the Monte Carlo. Something odd seems to be going on and maybe there is a slim chance this could be a difference in the test jigs.

The only reason I bring this up is that all your prior versions are perfect. They run without any issues. In fact I played a few games on you latest freeplay version this evening. First couple of games were rough (my fault) but have a good game before calling it a night.

The patch to address the 10 million scoring for some reason didn't work for me and a few others. So, while we can try burning new ROM's again can you think of any other options? What else could cause the difference in the emulation and what we're seeing in the game?

Personally I am fine with the original 10 million shot and will probably keep your existing freeplay version in the game. I'd just like to help see this get fixed since others really want to have the new scoring in the game.

I don’t know if an inch shorter will still be too long. Once I find out what the correct length is I will pickup a couple at the hardware store. Would also like to see if the bolts were completely threaded or just partway. That is one of the reasons I had hoped to see a picture of the original ones.

What are the correct length of the legs that came on Monte Carlo? Are they the normal 28.5" as used on other games or a bit shorter? Just wanted to find out what originally came on these games and the finish. (Chrome, Silver, black, etc)

Well that explains why my game is taller than my others. It has the regular 28.5” legs on it now.

Actually it looks like my machine may be going to a new home. I'll be sure to pass along the info since they may have room for the topper. Unfortunately often have to avoid toppers since they are often too tall for the basement.

I'm tying up some loose ends on my game and it would be a huge help if I could get a couple reference photos from other Monte Carlo machines. In particular:

- Pictures of where the power cord comes into the machine and how it is attached and connected. (Want to ensure all that is correct)

- Under the playfield I could use pictures of the GI sockets. One of them that goes under the triangular piece of plastic by the flipper was pulled out and hanging. looks like it connected to the ground braid and a couple other wires. Again I want to confirm everything is correct. Want to put that back where it belongs and put a bulb back in.

Thanks!

In order to get free play a set of free play ROM chips would need to be burned. I had a set in mine but I sold the game and the person that bought it wanted the machine to take quarters only. Don’t recall if I saved them or wiped them to reuse. There are ways to use an old plastic coin mech to mount a switch in parallel to the coin switch to add credits too.

It would help to post pictures of your boards. Is there any battery damage on the MPU board? Some can get into the connectors used by the switch matrix. Also if the power board wasn’t touched it should probably have the 5V potentiometer replaced with a precision one. The original ones are junk by now and replace every one. Just did a set about a week ago for a Genesis which has the same board set.

Also a picture of the coin door wiring may help since I think it may have a slam switch on it.

The one small board on the large black heatsink is the 5V power supply. Towards the top is an adjustment potentiometer. I’ve had to replace many of those.

The rest of your boards look really good. You have an aftermarket MPU with NVRAM

You already have a good MPU board and it already has NVRAM on it. All set there. Nothing needed.

Maybe but honestly I prefer the original board that is already in the machine. Just a quick update to replace that one control, resolder any cracked solder connections, and then adjust it on the bench is all it needs. I've done that to all of mine and they run fine. Costs a lot less than the replacement board too.

The only machine that I recommend a replacement power supply for is the earlier System 1 games. Usually better off on those.

There is but it has been a long time since I've had to do that and I need to look back in the manual. Would definitely try that first.

Monte Carlo does need all three regular size pinballs in the trough or it won't start. When I originally got mine it had a large ball in the roulette wheel, and two large and one small in the trough. One of the many reasons it wouldn't work.....

Picture of an updated power supply with precision potentiometer installed.

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You can get them from places like Digikey, Mouser, etc. Last time I bought some I think I ordered 50 of them. They are the sealed precision potentiometers. I prefer these since they are sealed and also thet aren’t sensitive to vibration and shaking as much as the others.

Sure. Mouser 652-3296Y-1-501LF

It is a Bourns 3296Y-1-501LF 25-turn trimmer resistor. Not only are they sealed they offer a much finer adjustment and even if the adjustment screw is bummed it won't change the value as drastically as any of the regular ones. That is why I switched to these.

To close the loop on this the issue ended up being a bad 74LS04 at Z12. That chip handles the Strobe 0 and Strobe 1 that are used to read the switches on the roulette wheel. The MPU and power supply were dropped off yesterday, fixed them last night, and they are back in the machine working well. Put a precision trim pot on the power board too.

Check voltages first. Di you have a solid 5V at the MPU? If not it may be time to go over the power board. I typically install a precision trim pot and reflow teh connector pins.

You can try reseating the cable connections too.

It would help to know if this is a new game doing this or one that was working fine and just started doing this.

I think every game on pinside was working fine until it wasn't... Really need a dew more specifics. Have you had it for a while and was everything playing well for you up to this point? Simple yes or no is fine.

Do you have the manual for the game? If not you can order one from pbresource.com Having the manual will help.

If it stopped working then you need to start by checking power. There are some excellent troubleshooting tips on the Gottlieb System 80 section of pinwiki.com

The original potentiometer on the power board does fail. If it does the 5V could be missing, low, etc and it will cause all sorts of issues. Best to measure and see. Also the pins on the connector where it is soldered to the board can crack and need to be resoldered.

Can you post a picture of the MPU board? Does it still have an on board battery? Are there signs of battery corrosion? If there was it may have gotten into the connector pins too.

It is supposed to have black rubber sponge washers but that red felt actually looks pretty good.