troubleshooting arcade machines..

[kramer]

ok guys, i'm very new to this so bare with me.

pc's are more my thing, but i have a general understanding of electronics.

 

Virgil suggested i post it here, the following is a message i sent to him this morning..

 

 

"

hey mate,

thanks for your reply!

 

basically i bought a leisure and allied cab. everything appears complete. i have a reasonable knowledge of electronics, but this is my first cab so i dont know much about it.

i checked all the wiring as best i could,

from what i can gather it's like this..

 

240v in goes to a long rectangular panel that splits it into 4 outputs. there's a big transformer which i'm guessing steps down to 110 volt, and another which has labels for like 12 volt and others around that range.

theres a power supply ( not a pc one) but has 12v, 5v etc. has a little knob on it. not sure what for..

5v adjustment mayby?

 

has 2x 20c oldham coin mechs, which i've managed to get one working, and a odometer thingo that's been disconnected ( 2 orange wires hangin off the connector.

 

i think you guys call it a lowboy design. except it's not a lowboy. the monitor has a marqee above it and a speaker, all built into the cabinet. the speaker faces the screen basically. it's got a monitor that's rectangular and longer vertically than horizontally ( like widescreen vertically lol). from memory the monitor is mitsubishi branded on the back of the tube.

 

has a single joystick 2 buttons and a 1 and 2 player button. this is all an upright design. it's missing the coin holder box but that's not too hard to fabricate i spose.

 

it's got a time pilot board in it and a bigger board under that with sort of like an 40 or 60 pin ide type connector linking the two.

 

as far as i can gather it's got a jamma wiring harness, and has a edge connector than converts it to konami plugged from the cab's jamma connecctor to the board.

 

i've got no way to know whether any of the electronics are working, as soon as i turn the damn thing on it blows the fuse in the 240v distribution thingo ( that thing also has a main power switch which cuts the positive power only, according to my multimeter.). i've tried 3amp 240v fuse and went to 5 amp 240v but they blow straight away.

 

cant really find any info on troubleshooting them, and monitor repair is likely out of my league.

 

it's seen better days, and my goal was to get it to work and put space invaders in it and put it into a pub and make some $$.

 

last night i realised that running mame on it with a pc etc and charging for it ( commercially) was highly illegal and could get me in serious shit...i think.

 

any thoughts?

 

to complicate things, i'm in brissy at the moment,

but live in toowoomba, where the machine resides.

 

paid $50 bucks for the machine and so far spent $4 on fuses. so i dont think i'm doing too bad.

 

bit depressed that i cant seem to get her going.

all the ground wires appear ok.

there's a bit of aftermarket wiring which is really confusing near the transformers, and the other night while trying to figure out the wiring for the transformer etc i broke one of the wires off that.

 

do you reckon mame it and just keep it for home?

i really had visions of getting space invaders going on it and placing it in a pub.

 

how can i do that legally?

 

sorry about the huge reply lmao

kramer.

 

"

 

any advice on what to do would be appreciated people :)

this is i suppose the best place for it.

[GameDude]

Unplug the monitor and try another fuse, if it doesnt blow the fuse then your monitor chassis is stuffed, dont bother fixing it its not worth it...

 

If it still blows then disconnect the PSU see if its that. if it still blows your short is elsewhere and you may want to stop before you hurt yourself!

 

I do cab wiring, psu and monitor chassis if you want to revive it and not electricute yourself :D

[kramer]

dare i ask what a monitor chassis is worth?

 

i'm beginning to think mame is the only way to go here.

 

picked up a 19" flatscreen CRT today at a good price, and i have all pc components ( ~p2 450, 256 ram etc, ti4200, and also 2 thrustmaster joysticks that i picked up cheap from cashies a while ago. i think that's everything i'd need for mame..

would save buying a keyboard encoder and total build cost would be around $100.

 

less if i sell the old componentry.

 

it's an option....

 

will try unplugging the monitor chassis... its a pain since wires go everywhere from it.

 

any way to test a transformer?

i'm dealing with ~25year old hardware here...

[Davefjedi]

Dude if you want it for your self mame it....

sell the striped bits on ebay

if you want to make $$$ outa it you wont make heaps

you will have to spend $$$ to make $$$

nothing is easy

:unsure :unsure :unsure

[Mrvfone]

Wellcome to the fourm! :) We all try to help new people out.

 

Repairing Chassis can be expencive, Espescial if the FETs need replaceing. $15 a pop for some... But if you want to run it "as close to the original" it`s not that bad.. I probibly spend all up with Fets, and a re-cap, About $50~ per Chassis.

 

I don`t consider it not worth it.. as all my machines run them and i have inverstered in a far bit of specfic test gear for them. I have been into electronics for many many years! So didn`t have to buy everything....

 

I replace everything and totaly re-wire each cab, It sounds like alot of work.. and it is... but once done.. it`s done. Probibly close to $300, New joysticks,buttions pre-maid harness (Beffed up and fused), new step down transformer, screws , zip ties, AT PC power supply, Chassis service ect...

 

What state you from? Probibly best to see if you can find some one local to give you some "On the job" advice ;) i`m sure one of the guys would be willing to help.

 

Mrv.

 

 

Unplug the monitor and try another fuse, if it doesnt blow the fuse then your monitor chassis is stuffed, dont bother fixing it its not worth it...

 

If it still blows then disconnect the PSU see if its that. if it still blows your short is elsewhere and you may want to stop before you hurt yourself!

 

I do cab wiring, psu and monitor chassis if you want to revive it and not electricute yourself :D

[Arcade King]

Yeah if its a 20" do yourself a favour and buy a universal chassis from Jomac. Can be cheaper than getting the chassis repaired as Mrv already said.

Just remember though when it comes to monitors and chassis you are playing with dangerous voltages, if your unsure about ANYTHING get somebody in that does or its :073:

[kramer]

i guess the issue here is that if i get another monitor chassis, what if the monitor's dead too, and the game board...

 

time pilot sux anyhow !

i want space invaders heh

[4_ur_amusement]

you guys just make things waaaayyy to hard

 

first check your ac cord a visual inspection to make sure the plug is ok

 

then with all the outlets disconnected from your distrubution box turn it on

does the main fuse still blow ??

if it does there is a problem with the distrobution box

if it doesnt blow start plugging in your outlets

power supply

top fluro light ( if the ballast in the fluro is blown it may well be the cause of your drama )

monitor ( if it uses your distrobution box most dont most are wired to the 110 volt side of your transformer although some did use 240)

the plug that blows your fuse with be the source of your trouble

[GameDude]

i guess the issue here is that if i get another monitor chassis, what if the monitor's dead too, and the game board...

 

time pilot sux anyhow !

i want space invaders heh

 

HE he I will have your time pilot if you dont want it:D

 

Anyway the chassis may be blowing because the yoke is shorted, thats the copper coil around the tube.

Out of all the potential problems the chassis/yoke is the most likely cause of your problem.

It is easier to replace the tube/chassis in one go but be carefull the anode on the tube is dangerous to handle, the tube can store dangerouse amounts of electricity if not discharged correctly.

The chances that the stepdown transformer or lights are causing a problem will be pretty remote but you should inspect the wiring for loose connections, frayed cables ect before doing had work.

I do carry spare tubes and chassis if you want and I can do a free quick inspection if you bring the whole cab to work here.

[kramer]

ok update, i traced one of the 3 pin plugs...which has some aftermarket wiring...

 

from distribution box ( pos neg earth) to plug ( pos is running straight back to the distribution box chassis earth ) what the f@#k was this guy thinking..?

 

that's positive straight back to distribution box.. surely that'll blow a fuse faster than oprah on a baked ham ?

 

i'm aware of those nasty anode's. i'll be very careful i promise lol. can't discharge it though, i've got no gear to do it.

 

in reguards to the monitor, looking at the yolk, one of the copper wires is sorta hanging off.. that's bad i think...

 

suggestions?

 

can't solder that wire back onto the step down transformer tonight as i can't find my damn solder.. got iron but no solder :(

 

will check distribution box though without the connectors plugged in. i ran a multimeter over it and every plug seems A1. will see if it blows the fuse though.

kramer.

[Virgil Tracy]

If this machine is at Goodna I will come around and have a look with you

[kramer]

thanks for the offer virgil, your a champion, but the machine's in toowoomba, where i reside :(

 

wont fit in the back of my nissan pulsar either !

 

just trying to figure out where the other 2 wires go..

 

question...noobish i know, but since i can't turn it on i can only guess what this thingo does.

 

it's a variable resistor with about a 3" long shaft, and has a momentary button... both are located on the same little panel, on the inside side of the rig

 

is it volume control and a service button?

 

what's the service button for, assuming it is one..?

[WOKA]

Service buttons used for for racking up credits..

 

See, I'm an expert - I can tell you what the service button is for.. ;)

[kramer]

what the... i dont need a service button lol, i've got access to the coin mech... click click click hehe

[4_ur_amusement]

well gd if you havnt seen lights and other things being the cause of some problems you mustnt of been doing this very long ive seen the on off switch being the cause of the problem ive seen fluro ballasts being the cause and a million other things have you ever heard of starting with the simple things first ?? before making it harder than it needs to be ?? maybe a chassis problem im not there but the same still applies transformers do go so do power supplies and chassis but doing the whole distrobution box thing is an easy way of checking rather than looking for and assuming the worst

[GameDude]

well gd if you havnt seen lights and other things being the cause of some problems you mustnt of been doing this very long ive seen the on off switch being the cause of the problem ive seen fluro ballasts being the cause and a million other things have you ever heard of starting with the simple things first ?? before making it harder than it needs to be ?? maybe a chassis problem im not there but the same still applies transformers do go so do power supplies and chassis but doing the whole distrobution box thing is an easy way of checking rather than looking for and assuming the worst

 

 

I personally see more chassis faults blowing fuses than lights.... also bad wiring ect but I cant see that through a forum post with no picture, just offering suggestions on the most likely problem.. not the least likely problem. For all we know there may be a dead rat in there somewhere causing a short.

Anyway we all welcome your suggestions as well, we are all here to help. :lol

[4_ur_amusement]

me too

[kramer]

just thought i'd keep you guys updated...

i've got the cab working now!!!

 

but everything is in the middle of the screen.... it's like stretched so that everything is

tiny horizontally, and normal vertically.

 

oh and no sound yet.

 

any thoughts on the screen issue?

[GameDude]

just thought i'd keep you guys updated...

i've got the cab working now!!!

 

but everything is in the middle of the screen.... it's like stretched so that everything is

tiny horizontally, and normal vertically.

 

oh and no sound yet.

 

any thoughts on the screen issue?

 

You have a collapse of the picture, commonly its the pots or bad/broken joints on the chassis. a multimeter and a good eye are all the tools you need to check for that. Pots can crack or break inside so the multimeter is a good tool for that.

visually check underneath the PCB for broken joints and damaged or craked tracks, you will need that good eye for this.

 

Also check your X-Y cable, make sure its fully inserted.

 

Other possibilities are bad caps which are easy and cheap enough to replace even if they are OK (worth a try)

or worse a transistor or something expensive.

[kramer]

hey mate,

caps look good,

the board is a kortex as identified my the prof ( big thanks for your help this far )

 

talked to a ex operator today. he said the 1 or 2 broken wires on the yolk may be stopping deflection. does this sound right?

 

i'm gonna be brave and discharge the monitor tonight ( never done it) and pull out the chassis, flip it over, and check for dry joints and resolder..

 

we're getting closer here! it powers up now.

[GameDude]

hey mate,

caps look good,

the board is a kortex as identified my the prof ( big thanks for your help this far )

 

talked to a ex operator today. he said the 1 or 2 broken wires on the yolk may be stopping deflection. does this sound right?

 

i'm gonna be brave and discharge the monitor tonight ( never done it) and pull out the chassis, flip it over, and check for dry joints and resolder..

 

we're getting closer here! it powers up now.

 

Maybe on the yolk, if its the wires going to it OK but if its the yolk itself not as good and also highly unlikely as they are not an item that is moved often enough to get a break in it.

Joints and Caps are my probably bet on the problem, also the pots.