Is it normal for a switcher to put out 12.7-13 instead of 12?

mhanlen1

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Is it normal for a switcher to put out 12.7-13 instead of 12?

I've just finished wiring a 60-in-1 up. It worked fine for 15 minutes, but then the screen froze, and I got a red blinking light on the board. My 5v is spot on- but my 12v reads a little high. Anywhere from 12.7-13.0vs- but it's consistent over this time period. Would this cause the board to freeze or have problems? The 60-in-1 is brand new. Otherwise the game plays normal. Everything else works fine. Could I have a bad board?

This switcher was capped by me. And unless I'm mistaken, the switchers won't allow you to change the 12v right? Just the 5v.
 
Yes that is normal BUT it shouldn't affect your 60in1 (or many other games for that matter) as, generally, the 12V is only used for the audio output amplifier and so is not critical. I have seen them at 10V through to 15V will no ill effects.

I think your issues are elsewhere - keeping in mind that the 60in1 might need 5.1V or 5.4V - they are all different between boards.

Also check that the ground and 5V wires running from the PS to the edge connector are VERY heavy gauge and measure the 5V AT THE BOARD - not at the power supply.
 
Yes, slightly above 12.000v is no big deal.

The part that scares me in your statement is that you "capped" a switching power supply. Did you use low ESR caps? Why did you do that, did you identify a problem caused by capacitors? If you're seeing proper voltage then it's probably ok, but depending on the switching frequency those things can be a lot more sensitive than your average early 80s technology. For hobby-use I usually consider them disposable if there's any problem; a cheap replacement is only $20 (link). A high quality replacement is only slightly more.

Call whoever sold you the 60-in-1 board; any reputable seller should be able to provide technical support and should warranty their equipment. It's JAMMA right? So find somebody locally and test it in another known-good cabinet. If your board is working properly, then my wild guess is your power supply cannot source enough current and you need a better one?
 
Totally normal and for the 12v line it doesnt really matter anyway. The 12v is related to the 5V in that when you crank up the 5V the 12V will also increase. It doesnt matter tho because on almost all modern boards the 12V is only for the amp chip, and these are usually happy with anything from 9V to 20V.
 
Thanks for the help guys. I know switchers are disposable, but I've capped them before, and had no problem. I really don't like throwing anything away. The power supply seems fine, I check it frequently and the voltage is always the same.

Unfortunately this is my only cab and board, otherwise I would have swapped the things out already. I have one of the newer small 60-in-1s that everyone is selling, I will see if the manual has any specific voltage requirements above 5.0. I will also check the voltage at the board to see what its reading.

Thanks again, I'll report back.
 
Checked it at the board it read 4.9. The manual states 5.0-5.5 volts (cannot exceed 5.5). I upped the 5v to 5.2 (measured at the board), and I'll see how that works. I'm going to leave it on for several hours.
 
No dice. Eventually it goes to a black screen with a reddish/brown horizontal bar. There is a red light on the PCB that flashes when this happens. So this morning, I tried running the switcher straight from the wall, to try and eliminate the Atari power supply it's tied into as the culprit. Locks up again. Ok, next up... well I found another switcher that was a little dusty, to I put that one in there- checked the voltages... adjusted the 5 v to 5.15 and then hooked the rest of the wires into the switcher. Still does it- even with another switcher. You can always switch the machine off and right back on and its fine for several minutes to an hour. I'm leaning toward bad board? The JAMMA harness in it is brand new, by the way.

Any other suggestions? It'd be nice if I had a second JAMMA cab.
 
Check the connectors on the power supply and the Jamma edge connector. If the connections are weak they can cause problems as they warm up. The 60 in 1 board is more picky than many older boards, so this temporary drop in power might only cause problems on the 60 in 1.


Of course, the manufacturing quality on these 60 in 1 boards is suspect. The same heat problem can be present on the board resulting in your issues as well. I'd say look over the board for cold solder, but the surface mounted components make this more difficult.
 
One thing I'll add......are you using one of those cheap $10 JAMMA harnesses? If so, beef up a couple of the grounds and 5VDC from the power supply to the PCB. Those harnesses are crap.

Edward
 
I don't know if it's the same as the 48-in-1's (I would think it would be), they don't even need 12V for the audio. I have one of those JAMMA cabinet adapters in my Gaplus cab, and the 12V line is only putting out 5V, and I still get audio on my 48-in-1. I also get full audio on Gaplus, so it probably hasn't had 12V since I got it. Some of my other PCB's won't have audio at only 5V though, and some have partial audio, but its distorted.
 
The power supply seems fine, I check it frequently and the voltage is always the same.
With this sort of problem it's ideal to use an oscilloscope, setup a single trigger around 4.8v, and look for any occurrence (during the entire hour you're testing) that the power dips momentarily. The multimeter shows you the voltage when you're looking, but it's not the best tool for observing a glitch or dip that might last only a fraction of a second.

There's not much involved with this hookup so I only see two possibilities -- either you're not supplying good enough power, or the board is defective. And if the board is defective then your only option is is to call the company that sold you the board and followup as a warranty issue.
 
Yep Ed, it's the $12 harness. I just soldered a few heavier gauge wires to the ground cluster and ran them to the switcher ground to see if that helps. Although the ground wire in the harness is as thick as the 12v and 5v wires. I've used the cheap eBay JAMMA harness before and didn't have any problems with the slightly larger iCade. I've got the new, smaller version in this one.

No oscilloscope sorry. The voltages look fine, they've been identical everytime I have tested them. The monitor that runs off the atari big blue power supply works great- no problems. I also have a new big Blue on it as well. The FG on the switcher running to the atari power supply wouldn't be causing this right?
 
Check the connectors on the power supply and the Jamma edge connector. If the connections are weak they can cause problems as they warm up. The 60 in 1 board is more picky than many older boards, so this temporary drop in power might only cause problems on the 60 in 1.


Of course, the manufacturing quality on these 60 in 1 boards is suspect. The same heat problem can be present on the board resulting in your issues as well. I'd say look over the board for cold solder, but the surface mounted components make this more difficult.



Also, I've pressed on the board, and checked for cold solder- nada. I can't recreate this problem by tugging on wires, pressing on the board, or jiggling connectors. It happens when the machine isn't being touched. Again sometimes it's 5 minutes in, and others it's nearly an hour before it does it. Most of the time though it's 15ish minutes.
 
The monitor that runs off the atari big blue power supply works great- no problems. I also have a new big Blue on it as well. The FG on the switcher running to the atari power supply wouldn't be causing this right?
Based on what you describe the big blue capacitor is not even used. That capacitor performs filtering if you're are using the original linear power supply. The monitor uses the 110v isolation transformer but nothing else. So if you've installed a switcher to replace the original linear power supply then you're wasting a $15 part having a new big blue capacitor in there.

Right now it sounds like you've run yourself into a corner. You don't have a known-good cabinet to test the board in, you don't have a high quality power supply to swap-in, you ruled out power but don't have the right tools to test it, you haven't sent the board back to the seller for a warranty issue, you don't have a lot of stuff.

You need to figure out some way to remove one of those limitations. There are three pieces under your control: power supply, wiring harness, and board. One or more of them is faulty. Maybe hookup with another collector locally who has the right stuff and is willing to help you out.
 
Based on what you describe the big blue capacitor is not even used. That capacitor performs filtering if you're are using the original linear power supply. The monitor uses the 110v isolation transformer but nothing else. So if you've installed a switcher to replace the original linear power supply then you're wasting a $15 part having a new big blue capacitor in there.

Right now it sounds like you've run yourself into a corner. You don't have a known-good cabinet to test the board in, you don't have a high quality power supply to swap-in, you ruled out power but don't have the right tools to test it, you haven't sent the board back to the seller for a warranty issue, you don't have a lot of stuff.

You need to figure out some way to remove one of those limitations. There are three pieces under your control: power supply, wiring harness, and board. One or more of them is faulty. Maybe hookup with another collector locally who has the right stuff and is willing to help you out.

Whoa wait a sec. I just got this board in the cabinet last night and sought advice- it's been less than 24 hours. I received it earlier in the week. I wouldn't say I've backed myself in a corner. I've tried everything that has been suggested here that I have the ability to do-including swapping power supplies checking for cold solder joints, and beefing up my grounds. The big blue capacitor was bought and installed last year- no big deal- i didn't know the direction I was taking with the cabinet at the time I purchased it. And I have PMed the person here I bought it from- I did so last night. And I've let him know all the stuff I tried yesterday and today. I am awaiting his response. So as far as I can see, I am trying everything in my ability. Again, this isn't like I've been asking for help over the course of a month and not doing anything I've been told.

Anyway I'm waiting for the seller to get back to me. Also it seems to stop playing game sounds after a while- like the sound goes away entirely. So it leads me to believe the board may be flaky. I may post an ad here and see if I can get someone who has a JAMMA cab to let me test the board in there. But I don't know any KLOVers here or I would have hit them up.
 
Sorry it probably came off tougher than I intended. Power is quite likely; you've tested with two questionable supplies and all replies suggest this board is extremely sensitive. It seems most likely you'll succeed if you install a brand new high-quality supply from Happ. And if you don't, then at least you've ruled it out and you have a good power supply on-hand for next time.

If you have a good multimeter it may have high-speed min/max capture that can watch for any voltage-dip like I suggested with an oscillscope. See this article: http://www.fluke.com/Fluke/usen/community/fluke-news-plus/ArticleCategories/DMMs/
 
Yep Ed, it's the $12 harness.

Sorry!....Man, I just hate those things. They just scream...."problems down the road". From outward appearences, they don't look too bad.....20 gauge wire, maybe. Then you cut one and strip a bit of insulation.....WTF....24.....26 gauge wire. It's the tiniest stuff I've ever seen a harness made out of. It just has nice thick insulation, to make it appear of a better gauge.

Edward
 
Sorry!....Man, I just hate those things. They just scream...."problems down the road". From outward appearences, they don't look too bad.....20 gauge wire, maybe. Then you cut one and strip a bit of insulation.....WTF....24.....26 gauge wire. It's the tiniest stuff I've ever seen a harness made out of. It just has nice thick insulation, to make it appear of a better gauge.

Edward

And it is not copper wire!
 
Ok, swapping in an ATX. By doing this I'm eliminating the power cables from the cheap JAMMA harness, and the 5v, and switching power supply thing. The guy who sold it to me, said that the newer smaller boards require between 5.0 and 5.1, just FYI. Anyway I'll provide an update.

And for testing purposes, I have the ATX and the monitor running off different power switches for right now. It seems the iCade board is finicky about turning the monitor on after you turn on the icade. It gives an error message on screen. I don't know how it is with VGA, but thats how it behaves with an arcade monitor.
 
And for testing purposes, I have the ATX and the monitor running off different power switches for right now. It seems the iCade board is finicky about turning the monitor on after you turn on the icade. It gives an error message on screen. I don't know how it is with VGA, but thats how it behaves with an arcade monitor.
That's another symptom that suggests power issues. When you turn on the monitor there's a huge inrush of 110v AC and maybe you're seeing a line voltage dip.

Check where you've picking up 110v AC for the switching power supply. The monitor should be through an isolation transformer. The power supply should be past the line filter and safety switch but not through the isolation transformer.
 
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