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Everything posted by midibob

  1. Nope, no demos or tests pretty basic really. For testing you need the specific software which is in the downloads section but I think you have to modify the cart?
  2. Something to look out for on these old techs is all the switches are break (except for the coins) and you can get some really wierd faults if a switch is open circuit.
  3. LOL, I think I set myself up for that one.
  4. Yep, words of wisdom there. The 53v line can track over to the 5v and 12v lines along with the magic smoke and a barbeque'd board.
  5. Is that Arreton barns? Hopefully going in a few weeks time so must drop in.
  6. Wow £12 a throw!
  7. A good bit of detective work.👍 The only issue with the Ebay one is the tags probably won't fit in the PCB as they are too wide. You really want a pin ended one. Finding it as you you know is going to be tricky but you might be lucky.
  8. You'll probably need to get the side supports remade on a 3D printer as I reckon these are even more difficult to get replacements!
  9. I don't know how many connections there are on that card socket but ones that are similar are for the ZX Spectrum and there's quite a few places that sell them. I don't know what they are called but you can cut them to size if they are too big, if they're too short you're stuffed!
  10. The only reason it was Trick or Treat was I don't know what other games might use the additional sound ROM card, and of course if ROMs are available.
  11. Good stuff. Did some of the legs fall off the old ones, they usually do!
  12. Yep, both common cathode. The only thing you might need sunglasses with the new ones, as somebody on here said once they are F'Kingbright.
  13. In that case I would suspect the displays. Make sure all the connections are good to the yelllow plug.
  14. IC3 & 8 control the Alpha (amongst other things) which is working? Might be an idea if you post a high res pic of the board to see what condition it's in.
  15. If I understand correctly it's the one in your hand that's faulty but is that just in your conversion machine or any machine? I would probably say the displays were knackered in that case but it does seem a bit odd that they are all playing up unless you have a bad connection on one or more of the DATA lines.
  16. No, the tants just blow when they get old. If the +5v is good the red LED should be glowing? TP6 should have a 1MHz waveform. The volume pot will need changing if it's stuck but it wouldn't cause any of your symptoms.
  17. They don't match the CRC's of the ones I need so probably not. Thanks anyway.
  18. Hi folks, I'm trying to find a copy of the sound ROMs for a Procon (Project) Trick or Treat. I've searched high and low but can't locate any. Perhaps there could be a copy in a DX somewhere? The files are labelled 193SND1.000 and 193SND2.000 . The reason for asking is I've been donated a sound card by a kind member and I'd like to get it running as I've encountered a few faults recently which the main board runs OK with code not using a sound extension card but not code with a sound card. I suspect the problem is corroded tracks to the 64 way connector which aren't used in non sound card games. Cheers Bob
  19. Yep sure was. Removed it and back in the test rig and .......nothing! On closer inspection there was another one on the same connector so whoever looked at it previously put two obscure faults on it and then presumably gave up. After the second solder bridge was removed it burst into life.
  20. It's been a while and lots of MPU3's have passed under the bridge since the last update. A couple I did today have to be mentioned as they weren't the usual run of the mill faults. First one, reel 4 didn't spin. Most folks only have three reel machines but I always check the 4th reel in case the board is ever used in one. Normally it's the transistors failing (BCX38) but after swapping them out it was still the same. With fingers tightly crossed I was hoping it wasn't going to be chip failure especially the PIO (IC5). Anyway as luck would have it two of the resistors in the 330R network (RP7) were open circuit. On removal .... The next one was a real head scratcher. Once all the usual corroded bits had been swapped out it was time for a switch on and see what happens....... Nothing! No sign of initialising at all. The CPU was running and outputs were being fed out from the muliplexor chip IC9 (74LS138). No code was being loaded though and this usually means it's going to be a long slog. The RAM was OK which is also a first stop to check. There did seem to be some sort of activity and occaisional switch ons would fire triac TC2 continuously with also a single reel twitch. Being as this is fed from IC5 (6821) which is also the reels I thought I'd start swapping out chips from there. Just after I'd put the new socket in I noticed something else which I hadn't spotted before. See if you can see it. Sombebody's been here before!
  21. That's very kind. I don't actually own the machine but I'm sure the owner will drop you a note if he needs anything. Cheers Bob
  22. midibob

    Mpu3 PSU

    That would be OK although it only needs to be 50v, probably the same price though.
  23. It's not the easiest to find on here but try this... https://www.fruitemu.co.uk/ib/files/file/1743-acecoinsystemonehardwaremanualwmpdf/
  24. 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.
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