Jump to content


Mecca Supporters 2022
  • Posts

  • Joined

  • Last visited

  • Days Won

  • Donations

    10.00 GBP 

midibob last won the day on May 7

midibob had the most liked content!

About midibob

Profile Information

  • Gender
    Not Telling


  • Are You A Spambot Again?
  • Are You a Spambot ?
    Most definitely not.

Recent Profile Visitors

2504 profile views

midibob's Achievements

Old Fruity Maestro

Old Fruity Maestro (19/19)



  1. It's not the easiest to find on here but try this... https://www.fruitemu.co.uk/ib/files/file/1743-acecoinsystemonehardwaremanualwmpdf/
  2. Yep it's definitely in the downloads. I've done quite a few of these and they are documented in my workshop thread if you search for it. Things to look out for, all the resistors on the bottom row (and next row up) get corroded and I usually swap them all out as they fall to bits on removal. Watch out for the track under the battery, it might look good but you'll often find there's no copper under the solder mask (honestly)! The 15 way pins suffer too and sometimes the only sure fix is to replace them. As you've already pointed out the little caps in that area all rot as well. The RESET circuit can be a head scratcher so don't go looking for faults until you know it's all good. The 8212 chip does fail if you're unlucky. Make sure the TVS diodes haven't gone short.
  3. I'll just chip in here (no pun intended although it's not a bad one as it goes). This is for the older mod MPU3's (1&2) with the 74LS03 fitted so the RAM chips are 256Kx4. The later mods chips although the same physical size (18 pin) don't work in these boards as they are 1Kx4.
  4. This is an interesting old tech and getting to be quite rare these days. Luckily manuals and schematics are available (in downloads) which makes things a whole lot easier. Before starting work on this tech I cut my teeth on the System 1000 which is very similar in construction. I've yet to document that one but one useful part of the project is that both techs can use the same tester I've built along with Bell Fruit Black Box. Here's a quick outline of all the cards and chassis..... I couldn't get hold of any 22 way molex connectors but luckily I had managed to get some 24 way ones from Digikey for the 1000 cards and had just enough spares to trim them down. Starting with the PSU card. They used a very odd arrangement of obtaining a 5v supply for the logic. The main supply (15v) is dropped to 10v and this is then used as the negative for the logic chips, the 15v rail then making the +5v, if that makes sense. I did read an article about the reason for doing it this way and at the time it was the standard way to do it. Wish I'd read that first as taking initial voltage readings was extremely confusing. The next cards are the CPU's. Two types have surfaced so far, C1 and issue 3. The first is the C1 variant and the next two issue 3's but some have only one ROM no RAM and no battery components. The CPU is the 4040 24 way chip so it's only a 4 bit device. The clock and RST is generated by the P4201 chip top left and these are prone to fail. Spares are non existent! Next is the I/O cards. Triac and transistor ouput. Lastly the input card. Most the I/O circuitry uses the same or similar format of ACE techs right through to System one so there's no head scratchers there. Of course things would be too easy if there weren't any any at all and lo and behold we come to the reel deck. There's no documentation on this so it had to be worked out from the physical deck. The principle used is similar to the old mechanical Bell Fruit decks with studs and wipers except they took a leap into technology and made it all electrical. Basically the reel has 20 positions with various slots cut into an attached sensor wheel. This then has 5 LED sensors to report the wheel position back to the program. Considering the motor arrangement is similar to the Bell Fruit it's quite clever how it works. There are slots cut in the outside of the sensor wheel which locks/stops the reel when its associated solenoid is released. It didn't take too long to sus out that the 5 sensors are used to translate the reel position into binary. As I didn't have a reel deck I needed to be able to create one in software on my Arduino. The basic code has been written but not tried as yet due to PSU issues with the test rig but hopefully this won't take too long to resolve. My understanding is the reel sensors are read at every position due to the slots ( 1 per position) on the outside circumference of the sensor wheel. When the program knows it's at the correct position it releases the solenoid to stop the reel. Any old hands out there, please feel free to educate me if this isn't correct or you'd like to add anything. So far I've managed to get all the CPU's to run and a couple of PSU's. No I/O cards have yet been worked on as the PSU supply from my test rig doesn't have enough power to run them and a larger transformer is needed. Once sorted I'll update this thread, hopefully with a working system.
  5. At least we know the ROMs that are in the downloads do support the feature. As you say mine does spin the reels on startup.👍
  6. I had a couple of MPU3 boards testing today so I thought I'd investigate the 5 plays or 1 play and 4 coins from a 50p. I had a sneaking suspicion that it can be done and I was right! The dip switch, as already mentioned is bank 2 switch 3 on but it's not as straightforward as that. I think you may find it also has to do with how the coin tube switches are set. This is what you'll need to experiment with but on mine the right hand 50p coin tube has been tape'd over so the coin level switch is operated. As there's no coins in the tube (either tube actually as I only have one old 50p) normally the switch would be open. I haven't looked at the other tubes so it could be a combination of switches but I think you'll find that's what does it. Once you have then the dip switch controls that feature, odd it's not mentioned in the settings sheet?
  7. Blimey, have I had it that long!
  8. I did post the Cabaret 100 diagram and switch settings here a while back.
  9. 'Ding dong merrily on high' you might say.
  10. Indeed, I spent many an hour looking for something but there's nothing with the same footprint.
  11. You can retension them but because the metal has been tempered with continous heat changes it soon loses its grip again. I would always recommend new ones being as they are still obtainable.
  12. These ones were, it looks like they were filed or sanded down. Trouble with all things like this is the time it takes to try and clean them up. New ones would be the easiest method of course but still you have the issue of the female crimp in the plug also being loose so the thermal damage starts again. The female crimps can still be easily obtained but probably not for too much longer and they are slightly tricky to remove from the shells. With a bit of practice though you can get them out with a couple of jewellers screwdrivers.
  13. Well, I think I've been on it for about 8 years now but haven't given up yet. I must be mad.
  14. Hi chaps, The never ending MPU3 connector saga continues. After many years of searching I've still been unable to source or find the part number for the soldered pins ie the PSU plug. This is what they look like and I've never come across anything like it. As you can see the usual heat issue as taken it's toll but has been made worse by somebody trying to clean the end. Checking with a new female crimp it didn't grip it at all! So the challenge continues to find a part number for this pin. These AMP comboline connectors were used in the aviation industry amongst other places but despite searching through various aircraft manuals I've never been able to find them. Stocks do exist though albeit in the US but like all these things if you don't have the part number you're stuffed. Part numbers are available for all the shells and all the crimps and these I've all obtained from the info that Rich supplied. (what a star)
  • Create New...