Pimp my arcade machine - Enigma II

[Russ]

Brilliant thank you! And lol they can bite, they can bloody kill you if you're not careful lol, I'm not going anywhere near touching that tubes exposed parts

Having gotten over the excitement and starting to play hunt what smoked I realised the transformer has a shiny finish, the glow I saw was just a reflection of the fuse toasting so I'm sure the transformer is ok

That link you sent is the same as mine, but without all the bodged wiring. I want to bring it back to really good condition and leave it as Enigma II as it's been in my family twenty years as that game

Cool I'll get taking it apart later and get photos of each board individually. I have a bench top power supply I can rig up for some power if it helps with testing.

Thank you very much again, can't wait to get back and try it again now

 

[twoforty]

Don' worry too much about the tube High voltage( about 14,000 volts ) on a black and white monitor.....pretty much all of them discharge after a few minutes of being switched off. If you want to take the tube out get a wire with a croc clip at each end, attach one end to one of the metal ears of the tube and the other to the shaft(non insulated) of a flat blade screw driver....slowly slide it unter the cap that covers the HT cable on the tube...I very much doubt it will crack (discharge) but it's better to be safe. You can then pull the cable off and unplug the neck board off the back of the tube. Obvioulsy don't turn the game on with the tube out!! lol now that would hurt

 

[Russ]

Ahh, I've just had "DONT TOUCH IT OR YOU'LL DIE!!" beaten into me from working with lots of pc monitors

Nice to know it discharges fast, it's been off 24 hours now. I think I'll try to leave it all in place but as per usual curiosity will overcome me and I'll want to practice/learn how to remove one safely. I'll do my best and if you don't get a reply to this thread don't feel bad that I didn't make it... it was my own fault

Thanks again

 

[twoforty]

TAITO COCKTAIL - POWER SUPPLY BOARD on eBay (end time 12-Jul-09 19:30:47 BST)

 

[Russ]

Brilliant thank you! I've had no time lately, but can I test that component on mine that typically goes before I replace it in case the problem is elsewhere? Or would you bet your 240 on it that it's gone and I should just buy one and be done with it? Need to save my money atm so trying to avoid unnecessary purchases

 

[twoforty]

Yours can be repaired no problem . Let me know when you get a chance to take amother look at it .

 

[Russ]

Got it out last night...

Generally looks ok, however you can see some water or something has gotten into the board over the years and it's kinda de-laminated. It appears the tracks on the board are in tact, but maybe better with a new one? Or do they all go like this?

Cheers

 

[Russ]

Bumpety bump Wanna get it working, far too much of

Visitor - "Awesome games machine"
Me - "Why thank, yes you're right"
Visitor - "Switch it on"
Me - Various excuses and disappointment

 

[twoforty]

yes that is normal . If you want you can send that board to me and i will check it over .

 

[Russ]

I'm glad that's normal, I was worried that if it wasn't I'd find that all over the table. That's a very kind offer thank you!! I have your address on the members database so I'll pop it in the post tomorrow Without trying to be cheeky or offload work onto you is it worth me popping any other parts (the EPROMs maybe?) in with it?

Thanks again

 

[twoforty]

to be honest your best bet is to drop the whole game off and let me sort it otherwise it could take a very long time to find the problem . .

 

[Russ]

Hey twoforty,

About my arcade machine, is there a forum that'll be good for me spending the next couple weeks of evenings trying to get it working please?

I know you've been very helpful with my arcade machine, I don't want to keep taking up your time though, I know you said you'd fix it for me but I'd like to learn how to fix it myself

I'm getting fed up with people asking "does it work yet?" and the weather isn't quite good enough for gardening yet lol

 

[twoforty]

hmmm well there is jammaplus, there are some people on there that know a bit about games, to be honest though they will same the same thing
First verify your power supply voltages +5v, +12v -5v etc....if those are good then tryadding a coin and see if the game plays blind....then monitor is the problem....if you can see random graphics on the monitor then the game PCB is at fault, I would say its more than likely a bad RAM IC on the middle board...you can see a bunch of them right next to the processor....IIRC they are 2101's about 8 of them and they always fail, to fix it you will need to desolder the old chips (not easy) then fit sockets and new RAM IC's, that's the easy fix it could be something else and you could teach yourself about logic circuits from the 80's ...be prepared for some serious reading. I don't mind talking you through it but you need to start at the right place or you will be wasting your time, on the main PCB you will see the edga connector that feeds power and inputs to the board. Down load the pinout for your game and then start measuring voltages at that connector.... with your meter set on DC volts place the black probe where its says 0 volts or ground on the pinout sheet then place the red probe on the 5v pin... then move the red probe to the +12 volt and -5volt and the -12v if it has one.....post the results here and I will explain the nest step. If the volatges are good then you will need a logic probe for the next step Logic Probe : Test Accs : Maplin
this will give you an idea of the state of the data and address lines, download a pinout of the processor..i think its an 8080 on that game, then you can check to see if there is activity on the data and address lines atthe cpu, you will need to lay the 3 boards out flat on a bench and have the power connected to do this, you can also check to see if the reset pin on the processor if being held low or high... (low 0v, high +5v) if its pulsing then the watchdog if barking because the code from the ROMS is corrupt....could be a bad rom or data/address problem.

 

[twoforty]

Here are the pinouts for ENIGMA II



http://www.arcadeuk.com/pinouts/Enigma2.htm

 

[twoforty]

Space Invaders Manuals @ www.robotron-2084.co.uk schematics can be found here, probably much the same as the Taito 3 board space invaders part I and II , Enigma was a ROM change for those games.

 

[Russ]

Man, thank you so very much, the second I fix this I'm gonna renew your club membership or you can have beer to the equivalent value.

I appreciate what you're saying, there will be some cut off point where it's no longer worth me learning/investing time in trying to fix it as I've no ambition to do it again, just wanna get this one (it's actually my mums bless her) working. I'm a programmer by trade so I've got some logic and problem solving skills, but without some heads up I'll be there forever.

What I'm hoping is that it's just the (decrepit) power supply that's duff, I swap another one in and voila! A simplish fix. If it goes beyond the scope of that or something I can't fix without driving you mad with questions then I'll have to admit defeat and take it to an expert

I'll get stuck into that and get back to you, thank you again.

 

[Russ]

Ok cool!

I lifted the transformer, and get 14.4v between the two purples on the transformer. One purple (0) goes to the fuse holder, and out to connecter A, the other purple (14v) goes direct to purple on connector A. This connects to the PSU board and is presumably a good supply for the suspect board?

 

[Russ]

Ok so now I need to test "the 5v regulator and is probably the cause of your problem" Will see what I can learn from google

 

[Russ]

Ok trying to test the transistor, figuring that at the moment, get 427 ohm on one point and 451 ohm on the other. I have a bench top power supply I can use if needed to test it.

Have attached datasheet for the transistor and diagram for the taito power supply in case they're useful

 

[twoforty]

14v? you had your meter on AC volts right? best way to check the 5v regulator is to measure the 5v line with your meter on dc volts. You can check the regulator using your meter on diode check but you may get an odd reading if it has a resistor somewhere on the pcb connected across the regulator. There is a reset voltage that comes from that board upto the game board, if its missing the game won't run, you should check that at the edge connector also. Keep it simple at first and check the voltages at the edge connector or you will be testing parts you don't need to test