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Hi chaps, and chapesses. As I get MPU3's in various states of damage one of the most usual things is the cart holder is either missing or broken. As everyone knows without the holder intermittent faults abound due to vibration. Trying to find spare carts is more or less impossible so I thought I'd have a go at knocking up a 3D version. Here's the 2nd attempt, the 1st one the mounting holes spacing were about a 1mm out. I can probably use it but wanted a good one straight off the printer. Having said that it does need a little filing to ease the connector in but everything lines up which is the main objective. I will install it this afternoon and report back but so far all looks good. The rough bits on the bottom are where the supports have to go to enable the raised bit which takes the metal brackets. I cut those off with a small chisel. If there's any interest I'll post the STL file so you can print your own or if you want to improve it. All I ask is you post it back here so I can use it as well.

easy one

Found this. Wish I had a time machine...

My last visit was great. I did a tour video to update you all.

Yep, it does make it an MPU2. They obviously made these before the MPU2 was released to give the extra functionality, and then developed it into the MPU2. Managed to get it working today.

Hi all, I've blocked all fruit machine sales pages recently but this has been shoved in my face by Facebook as it's just on a general page, not a fruit machine one. I've no idea what it is. It's before my time and no idea if it's electromechanical, microprocessor based, or even who is it made by! Any ideas? Would it be worthwhile picking it up even if just for a project I'll never complete? Seller asking £60 which seems a bit much for what is 99.9% likely a non-worker. Ta!

Cabaret 144 jackpot😂😂😂

broken tracks by the battery as the battery leaks it kills the tracks by it

Jackpot Multiplier is a late 1970s, 2p play, electro mechanical conversion on what would have originally started as a Bell Fruit Ten Up electro The conversion build was by a company called ADMC or Automatic Development Manufacturing Company LTD who were based in Nottingham back in that era. The cabinet corner looks a bit battered but if it's complete inside and not been tampered with, then there is no reason why it should not restore and run again. Having said that, It looks like it's been stood for sometime and many of the timers could be jammed or seized so don't expect it run well if at all when plugged in. As it stands with the inner workings unseen so anything missing and it's spare parts so, About any offer up to £50.

Definitely electro! If the cabinet is good, it’s probably worth £60, these machines are quite fixable for sure!

We have all done it Ronnie! Many times, glad you got there 👏

So just an update on this ! I decided to check for reel voltage and I had none tracing it all the way back to the big diode I was confused why I had no power then I realised I fitted the p600 diode the wrong way round! Must have been a senior moment! Spent blood ages on this one, oh well at least it’s working now thanks Ronnie

It is mainly the RESET but before we go down the rabbit hole it might be a good idea to swap it out. If you can scope the 4 outputs from this chip and they look OK then maybe all is well. Like all these things that are intermittent sometimes it's best just to swap out to be sure, at least it's another thing eliminated. The part number for the TVS is 1.5KE6.8A (RS 171-9442)

Don't understand that Ronnie? If the 100Hz is going in it should come out as a nice 100Hz square wave about 5v p2p assuming the chip is powered ok. Pin 12 feeds IC2 (6840) and IC3 (6821) but I can't believe they would be causing anything.

I have a few 80s mpu4 game cards... I'll.check and let u know tomorrow ..

It's a tantalum capacitor so there's a good chance it has! Snip it off and try it again.

They shouldn't run hot, sounds like a chip has failed unless C1 has gone short?

Unbelievable 😂👍.great capture

Yep power's up straight away. Thanks so much for the advice really appreciate it. Will try and track one down now.

yes just put it in the working machine and see if it boots up

It could be, on pin 13 there should be a double half wave 100Hz about 3-4v pp and then a nice chunky square wave out of 12. I've had various faults here IC18, R85 and broken track between the big diodes and R85. Could be anything really but easy to locate. If any of those components above look corroded I just change them all. The vbatt (not actually called that in MPU3) is the voltage to the RAM and battery charger. As long as you have 5v at the collector of T61 you should be OK. I usually change all the components around the battery area as most times they all show green legs. Saves a lot of time looking for faulty bits that you're probably going to have to change anyway. I reckon you'll be senior pro MPU3 fault finder before too long Ronnie.

'resetting' on a mpu4 i found is likely something wrong with the switch inputs, I had a cart that would do this on the test rig and never did work out which switches needed to be where on it for it to continue. perhaps its similar for mpu3

Just a thought, what mod board is it? The early ones won't run the later games. Easy way to tell is if it's got a 74LS03 for IC24. I suspect you probably know this already but in for a penny....

Well it appears to work just fine so I'm well chuffed. All I need to do now is to find a source for the connector. Hens teeth would be easier especially as it needs the little spacer in the right place. Luckily I did have a strip of it but had to cut it both ends as the spacer was in the wrong place. That was my last piece too. If anyone knows a source I'm all ears. (brackets as well)

Can't see as it would as that error would be to do with the character chip either bad or missing on the cart? Although it does sound like it was running before so who knows.

Looking at the wiring diagram err 7 is a characteriser fault! (I'm assuming A/L is Adders and Ladders?)

Must admit I've fitted one or two the wrong way round too! Nice one ronnie glad it's working.

Wow what a shout.👍

Your best bet is to look on Ebay for '32mm fuse holder'. There's loads of different shapes and mountings. You'll have to buy the whole holder as it's extremely unlikey you'll find just a top.

Don't worry I've done it too

So Powered it on this morning fired straight up, instantly out of reset and booted! Surely it's not self healed! It seems since I scoped the 541 it has worked! Now if these mpu3's could only self heal!

I thought there should have been a pulse on 13?? I don't have my notes to hand to confirm and I'll be away for a couple of days but will check on my return. It's funny how it's stayed on though. It's doubtful if there would be any dry joints on that chip as MPS2 is pretty good in that respect.

So since I done this the machine has stayed on without any nonsense, must have been on 3 hours plus

Hmm, lots of head scratching going on this end. This has probably nothing to do with it but can you check the o/p from the 555 (3). It should measure between 500-660 Hz.

The chip does but IC20 only uses 4 so it's pins 11, 12, 13 and 14

I grew up on Ihe island but that place wasn't there until after I left. Did visit a few times in the 2000s when I went back to the Island for holidays.

Sorry if I've already said this but I'm rushing through my inbox trying to clear everything. Can you make sure there's no solder rings on the green connector. Might go for the red one too.

I would swap it out anyway as that one suffers the most being next to the battery.

You'd also better check for voltage starvation across TVS1 (next to the CPU). Should be 5v or thereabouts. If the PSU connector pins are dirty or lost tension it can drop below 4.7v and all funny things start happening.

I can't remember if I asked this but do the reel sensor lamps fire up? They should all come on together.

I'd stick to the existing type ie 74LS541 or even 74ALS541. I know there are some minor differences with the CMOS types (HC) that may (or may not) cause a problem.

Even though most of it isn't my tech (and all of it goes over my head), I absolutely love reading your posts Bob.

Yep always good to swap out those three transistors. If it takes a long time for the reset LED to go out it's possibly IC20 that's going bad. Any of those 4 IC's surrounding the CPU all suffer due to the battry.

Well,I have to admit..18 years have passed, and I'm still none the wiser. But my kids have grown, and left!! The bell fuit machine, I kind of recall. They had another called rubies and diamonds, which was a 2 quid / 4 quid repeater, respectively. System 80??. They could go mental, as Pete has testified. I don't think the resources have found these machines. Yet. Statto

Keep the good work up andy ,it's great that you have these machines up and running in the bowl.like nifty has said I'd happily spend money in your place if I lived nearer.

Something a lot newer. Timeless games X Bar 7 with Flintstones JP tune

This one came in as not booting. These are normally in quite good nick mainly due to the fact they don't have batteries. This model also had the later type of regulator using the TO3 device, like MPU3. The only other odd thing was that the ROM cart was an MPU1 version but running 'Rock on' which is an MPU2 game. First thing was to swap out the old cap. On a power up it would light one of the lamps but nothing else. Looking at the CPU it would start but after a few seconds all activity from the data and address busses would stop? Sometimes they would start pulsing again after 10 secs or so. All very odd. These boards use the 6800 CPU and I didn't have one to substitute and as it appeared to be sort of working I was reluctant to splash out on one until I'd tried everything else. So, after replacing all the 6821's and 6810 RAM I was getting nowhere. All the original chips were put back in and the board was put aside waiting for the CPU to arrive. After a few days it landed on the doorstep and it didn't look like a fake when inspected which was a relief. Putting it in and powering up resulted in still no boot but there was a noise from the speaker and some different lamps flashed. So it was out with all the 6821's again which made no difference. Then the 6810 and bingo she lives! All the original 6821's were OK too so they went back in.

That's funny, I sometimes think somebody's got my other half especially when I'm stuck on a fault!

That is a mask programmed ROM, which contains common code used in all the games. Normally they are SCM39199 which is a motorola device