Jamma PSU problem

[strykr]

Hi all,

My Videowizard cab seems to be messing me about. I bought it and it was fine when powered up first time, then quickly the problems arrived. The latest one is with the Jamma PSU, It had one in there that was working fine, but after a week or so it bit the dust giving out nothing. Not knowing the history of the cab i thought a safe bet was to replace it with a new one. So I installed it and it worked for about a week, now the red indicator LED has gone, and the voltages it's giving out are all over the place, and the dial to increase/decrease doesnt appear to be doing anything.
This hints at a bigger problem with the cab, any ideas where i should start troubleshooting? any advice appreciated!

 

[stevearcade]

Just to second this, as the I was guy who was poking this thing with a multi-meter about 12 hours ago. Same issue twice over, (well, sort of). PSU dies for unknown reason first time output nothing. The replacement is now putting out low voltages (like 2-3) on the +5v, no matter what you do with the dial. The LED is not on and 12v is jumping around between 7-9v

.

Is it coincidence that a second power supply's gone funny? Is it possible that an issue with one of the other power devices in the cab is causing odd spikes that are knocking out the JAMMA supply?

The JAMMA power supply, monitor's brick, and the marquee light all come off the mains in at the back of the cab like normal. The wiring is clean, very tidy and organised with no signs of obvious damage or dodgy operator antics if that's of any help.

Please help and Strykr's just got an original 1942 that we're both dying to have a crack on

.

 

[andyman]

Is it happening with any pcb in particular ?, is there a mains filter before the psu ?, anything high current powering up around (i..e compressor or something else with a big motor), definitely sounds spike related.

Also what line voltage do you have as your mains as PSU expects between 220-240

About all I can think of tbh

Andy.

 

[strykr]

Is it happening with any pcb in particular ?, is there a mains filter before the psu ?, anything high current powering up around (i..e compressor or something else with a big motor), definitely sounds spike related.

Also what line voltage do you have as your mains as PSU expects between 220-240

About all I can think of tbh

Andy.

Ive been afraid to whack a PCB in tbh andy until I was able to confirm a stable 5v, It's a mame and Jamma cabinet via a J-pac, want to put a switcher in and play my favourite PCB's and also switch over to mame, like stevo's set up. J-pac in or not the voltages are all over the shop.

I have no shame in admitting Im a dunce when it comes to electrics. So over to you Steve?

I can say there is no mains filter tho, and the only things powered up around it are two other cabs.
strykr2012-01-20 12:01:02

 

[andyman]

PSU maybe needs a load attached before you will get stable voltage, most new ones do.

You need a test pcb, haven't you got a Streetfighter martyr ?

Andy.

 

[stevearcade]

The input's pretty high. My meter's reading between 240 and 250v which is a high really for mains I think. But then nothing else in the room is breaking and everything is running fine. I guess we can't speak for Rich's neighbours in terms of what they are using in terms of compressors and the like. Do you think a 10VBAG5 line filter before anything is good route to go down?

stevearcade2012-01-20 12:27:53

 

[andyman]

Cant hurt to try, might even have a spare somewhere I can chuck in the post, check resistance on loom for power cables too, you want close to zero, you never know what bodges there are hidden away.

Andy.

[edit : I knew what it was

]
andyman2012-01-20 14:31:38

 

[stevearcade]

Thanks Andy, take another Medal out of the bucket

.

By check the resistance on the power cabling, I assume you mean in case they've used cable that isn't mains cable and therefore under 13amp? Is this right?

I've got a line filter we can try, but I don't actually know if it works as it's old and has never been tested since I've had it. So maybe Strykr might take you up on that offer of the line filter in an envelope

.

Test board for the voltages and creating a load to put on the PSU you say. Looks like we better dig out the Pocket Gal 2

.

 

[andyman]

Bucket's empty mate

Nope, in case there are just about joins wrapped up with tape etc, you don't want to much resistance, things get hot and break/burn out. Doubtful it would be enough to kill a psu but worth a look.

Not much goes wrong with filters either, so give it a go

SF is the universal test pcb, just ask around on here

Andy.

 

[stevearcade]

Cheers Andy. I'll get on the case. And it will be Pocket Gal 2 getting put through her paces after this.

 

[strykr]

Looks like mr Steve is all over this,

Thanks for the advice Andy, a gent as ever. Would like to take you up on your offer if thats ok? you coming to the Slam? Im sure i can shout you a beverage!

Im still concerned that the red LED gave up after a day. and the fact that 3 other cabs seem to be running fine, off the same mains circuit leads me to beleive it must be a wiring problem in this cab?

Theres no such thing as a street fighter martyr.

Theres no better time to have a Pocket Gal PCB in the family

strykr2012-01-20 19:30:49

 

[andyman]

Ok, I'll try & post it tomorrow

 

[stevearcade]

Legendary! You realise Andy, you're almost single handedly managing to keep the Eastbourne wing of VAC in gaming with the cabs, control panels and tons of advice

. On that subject, just for the future, I'm looking online and can't find anywhere that sells the kind of filters I have in mind (the one I asked you about some time ago - that was in the Daytona I got from you). Do you know anywhere that sells them? Do they go by another name that they may be listed under?

Rich, we'll gut the cab next week and trace all the power wiring, fix/replace anything suspect. Also, hopefully the PSU's internal fuse is all that's blown and we can sort that too. I imagine it's a slow-blow fuse of some kind.

But take out the power supply and take the case off, there should be a fuse fitted to the board inside. It will probably be a small glass fuse, smaller than a mains one, and you can see the broken wire inside that will have failed. There will be a code printed on it or embossed on the metal cap at either end. Let me know what it is as I might have one either at home or at work (you might even have one in amongst you arcade spare part stash). Failing that, it'll probably be a 30p job from Maplins.

We'll replace the fuse in the PSU, fit the filter from Andy at the power input stage of the cab, amend any suspect wiring and go from there. That should safe guard the cab as much as possible from any suspect inputs (spikes in voltages). If that doesn't work, at least we've eliminated one potential cause and it won't have been in vein as it's always good to have clean wiring and a line filter. I understand line filters are common on cabs, and it just seems that every dodgy old JAMMA cab we've ever bought hasn't had them

. But from what I understand a good quality cab (normally dedicated cabs) have them. So it's only a good thing.

 

[strykr]

Ok, I'll try & post it tomorrow

Cheers Andy, as ever, much appreciated!

 

[stevearcade]

Please excuse my ignorance regards reading circuit diagrams here, but assuming this EMI filter you're sending Andy will look something similar to this:

which way round do I wire it

? I.e. which side am I putting the mains in? Line or Load? And what do I do with the earth from the load side? Do I just put both earths together on the line side? It's gotta go somewhere right?

 

[andyman]

Nearly

Line is the mains side, load is whatever you put onto the other end, earth for the load side is the metal casing.

 

[stevearcade]

Nice one Andy, and 10 out of 10 for the rapid reply

.