Leaderboard

OK, the first thing is this is probably a MOD 2 board being as it has a 74LS03 as IC24. The output is now on pin 11. Does it come out of RESET? On switch on it should stay LOW for about 1 second then go HIGH. Do you have the correct RAM fitted, it takes the smaller RAM (in Bytes) 256x4. HM6561 or equivalent. Because of this it won't run later games. T62 doesn't appear in this revision of the board as it has a thyristor (T56) in the RESET circuit.

Hello everyone. I'm back for a short month. Maybe enough time to repair my second MPU3, if anyone would be willing to help. It won't start. I've replaced the capacitors around the regulator. The 104 capacitors on the MPU, the RAM (NOS), and the transistors in the reset area. (By the way, I don't know where T62 is on the schematic.) So, here are my readings based on what I've read about the MPU3 and my recent experience getting help from Midibob. IC24 74LS03, yes, new. IC10 Pin 3 - 561 Hz square wave. IC18 Pin 12 - 100 Hz R83-84-85-D43-C39 100 Hz R68 and R69 OK C32 and C34 OK IC24 Pin 8: I can't find 2 Hz; nothing. IC9 Pins 10 to 15: only high levels (logic probe). All components in this area have been tested or replaced if suspected. D44 and D45 are also new. No corrosion on the RAM sockets or underneath. Cartridge port is also free. Ah yes, the 5V is at 5.2V. The circled area contains all components that have been tested or are new. So, if you have any ideas where to look, I'm all ears. And whatever happens, we won't throw ourselves into the Thames. :)) Thanks in advance.

You'll tell me; look at your first repaired MPU. !!! Make some comparisons. It's back in its machine and working perfectly thanks to you. I don't want to touch it anymore. Okay, I'm going to investigate my problems. Thanks

Hello experts So, Bob is right. I installed the wrong component: T56. 🙄 I was really incompetent. This board has already been repaired, and the previous owner installed the wrong component, BC172. I always check the component and the schematic; and on the schematic, it's a BC172. Hence the mistake. Now it starts; yes; Bingo! 🙂 😀 Thank you; thank you again. But, well, there are some problems: The sound; I'm going to replace T11. The display is acting up a bit. One scroll bar is stuck in HOLD mode. And others... I'm going to check the connectors, the soldering, etc. Thank you very much.

T56 should be a thyristor? 2N5061 or 2N5060 at least that's what should have been removed. You had better check!

Good evening, everyone. Thank you for taking an interest in my problem. So, T56 = BC172 (new) As are T57, T58, T59, and T60 (BC172) (new) T61 = ZTX510 (new) I'm going to do some checks, track checks and others. Thanks; have a good evening.

Good Morning, Reset line is on pin 34 of all the 6821`s and a few other places, also easier is the test pin above the power socket, see pic. Connect your logic probe, turn it on and report back what happens. 👍

No worries and like you ive played quite a few clubbers and still do and much prefer them to awps . Im pleased there are still one or two still about .

Welcome back and great to read up on another machine post (youve done one or two 😉)yes sadly the mecca isn't as busy as it once was but is still a good place .sadly or happily there are many new forums on fb which have poached members which was always going to happen . Mmm yeah id agree with you on almost most points regarding nbn . It really wasn't a great game and desperately needed new features injected into an oldish idea . You could almost say it was made for the bingo hall environment and perhaps it was but I dont remember playing any in seaside arcades but oddly im sure I remember seeing at least one .I use to own one ,having purchased it from the late Mike stead (mds) and didn't gel to it .I was never a fan of the double/ nothing gambles these later mpu3 gave and much prefered the roulette wheel or straight ladder climb/reel spin type gamble of earlier machines . Each to their own pete but razzle was a far better machine in my opinion and possibly fortune numbers too even without an exchange when compared to nbn . I think it was an ongoing thing with barcrest and its special/super series win spins that they were from the outset very mean and we never got what we expected even with the club machines. Oddly the club machine s even stated a maximum of £100 could be won off special series but it never happened of coarse . I think the writing was on the wall once the tall cab came out with the likes of strike a light and odds on as nothing new was really injected into the mpu3 game play with odd exceptions like razzle and autoroute .it was only at the end of the mpu3 reign that big shot showed promise . I'd give naughty but nice a 5/10 too as I do like the sounds and artwork very much . Oh and just one thing you didn't mention was the intended inclusion of a scavenger type mech to accept 1p/2p&5p coins for credits. The only other to include this was autoroute both using em5 mechs which were very unreliable .what was going through the minds at barcrest was anyone's guess but probably a arcade owners worst nightmare sifting through 100s of 1p and 2p coins ! Imagine putting in 10x1p coins just for one credit 🤷🤦. Anyway great write up and most enjoyable and hope you can do a few more .👍

Classic 777 Heavens graphic layout will be released later this month. Forum member, Thompy, has been supplying me high quality images and technical assistance from his own machine over the last couple of years, just recently he has supplied vital lamp numbers so the emulation can be released with almost 100% accuracy. . 'Thompy' also supplied video and sound of the pull handle mechanism from his actual machine and thanks to our late, great, mfme author, Chris, it is now incorporated into mfme. J