Is my MVS setup safe?

I've got 2 MVS boards with sound problems, 1 worked fine for 6 months, the other, I'm pretty sure it was dodgy when it arrived, but I am worried that there's a trend here.

Before I go looking for another MVS, I wouldn't mind people looking over my setup.

Nothing fancy, just a wooden box.



But I have the board sitting above the JAMMA PSU.



I have the board sitting on some rubber grommits, there's about a 10-15mm gap between the top of the PSU and the board.
Could a close proximity to the PSU, like this, cause problems?

are you having heat issues? you can try installing a fan.

I personally wouldn't put the power supply underneath the board. Heat rises you know.

shadowkn55 said:

I personally wouldn't put the power supply underneath the board. Heat rises you know.

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Also, the power supply's external case seems to be electric-conductive. And the underneath of an MVS board has some soldering points, that could lead to a short circuit.

Regards.

Like everyone said, that power supply doesn't have a way to vent out of the enclosure very well. Add a ventilation inlet on one side and another vent on the other side with a fan blowing out for good circulation. Many sound problems are due to capacitors failing and will need replacing.

I like the enclosure because you can easily swap out boards. But I would really take the PSU out and put it in it's own case (with vents).

Those PSU's don't heat up very much tho.
I would rather still not have it that close to the board.

If you're considering keeping it in that place, at least get some PCB legs and you'll get some extra mm's in height.
It'll keep the board away from direct heat.
But again, those PSU's aren't really hot. At least when operating 1-slot boards. Id' rather still play it safe.

Looks to be a board problem,cant imagine the psu heating up that much in order to affect the board but i could be wrong.Try repair it yourself before taking the plunge again.PM the gadget or google that problem and prepare get the soldering iron out.Good luck.

I don't think the heat from the PSU will be an issue - although the PSU does look enclosed there - you really should have some air vents with a fan to allow air flow. How close is the bottom of the board to the PSU chassis? It looks pretty close to me - I would be tempted to isolate the underside of the board with something none conductive to ensure pins aren't able to touch the PSU chassis. Have you measured the voltage from the PSU whilst under load? The reason I ask, some higher power PSUs deliver more than 5v due to the lack of load. For example, you might find its reading 5.30v under load, which is one thing that will kill the Z80. I've had this fault myself where I am convinced my PSU killed the Z80 due to slight over voltage and I've since spoken to someone whos had numerous failures in MVS cabs where the voltage was over 5.25v. An ideal cab PSU probably has trim pots to tweak the voltages. If its a really good PSU you might be OK, but I would almost certainly start by measuring the 5v and 12v lines under load.

Thanks for all the feedback.

For anyone wanting to see my MVS woes, I have 2 other threads.
Original Z80 Error'd board
New board with sound problems
Original board worked fine for 6 months, 2nd board never worked properly, believe I got stung on ebay. Cheap board that came from Korea.

I don't think there's any chance of the board touching the top of the PSU, it's about a 15mm gape, you would need to bend the board, but I'll see if I can get some thin plastic from work to fit underneath though.

The PSU has a trim pot for the 5V line, been awhile since I checked it, but on load it was between 5.00V and 5.10V.

I didn't think heat was much of a problem with the PSU, problem is that there's no room inside to fit a fan, so I'd have to chuck it on the back or something. Maybe find a small 5V PC fan I could use.

Moving the PSU outside the box is a bit more work, while the box is as basic as can be, I didn't make it myself, did all the wiring, but not the actual woodwork, I have no skills or tools.
While I could just leave the PSU outside, I don't relish the idea of someone touching the mains line.
Are there any enclosures I could buy to house the PSU? Or are there better PSU's out there for this kind of job?

Been redoing the wiring on my box for awhile, also fitted a 12V fan on the back, but I'm running it at 5V to keep noise down, it's pretty much silent.

My new MV-1FZ turned up yesterday, so I took it into work today to try it out...and same fault, no damn sound!
Anyway, turns out that maybe I've been reading the wrong wiring diagrams, I was reading says said mono sound was on pin 11, changed it over to pin 10 and bingo. You have no idea how good it sounded to hear that Neo Geo splash screen tune. Plugged in the in the last board I bought and that worked as well, so a nice of mix relief and boiling rage at missing something so simple.

I still need to wire up the controller ports, been rather slack, but something I noticed in the 5 minutes I tried the board before I left the pub, the sync seems to be playing up, sometimes when you turn it on, the pictures all over the place, also the picture seemed to go dim and return to regular brightness at irregular intervals. Again, I've not finished with the wiring or spent any time looking over the boards, or it could have been the TV at work. But I was thinking it's time to get a new SCART lead. At the moment I'm using an AES cable I bought from Retro Gaming Cables, should I buy another, or get 1 of their CMVS cables? http://www.retrogamingcables.co.uk/cmvs.html

Glad to see you finally got it work. At least you have a spare working 1 slot now.

Do you have any resistors or a sync cleaner on the sync line at all?

Only wires I've put resistors on is the red/blue/green signals. I have no idea what a sync clearer is like.
I took apart the SCART lead today at work, there is a resistor between 2 pins. but I didn't get round to seeing which wires they were.

That resistor is probably between pins 8 & 16 to set auto switching and put the display into RGB mode. Try a 1k resistor on the sync line first, that might help.

Thanks for the info.

I always get a little anxious when ordering components, this the thing I need? http://cpc.farnell.com/te-connectiv.../dp/RE06233?in_merch=Products From This Range

That'll do fine. Not sure how much the postage will be if you're just ordering resistors (unless your just adding to a work order or something). These are the same (just select 1k ohm from the drop down box) if the shipping is extortionate:

http://www.ebay.co.uk/itm/Resistor-1-4W-1-from-0-ohms-to-10M-Pack-of-20-resistors-/301220021958?pt=UK_BOI_Electrical_Components_Supplies_ET&var=&hash=item46221cc6c6

Thanks ordered, got a CPC account at work, so don't have to worry about delivery charges.

Well it's been a long time coming, but my baby's finally back home, thanks to the help on this forum.

Ladies and gentlemen, I give you the MVS Box Mk 1.1, with extra cooling!







It's damn nice to have her back.

That vent looks a little overkill - har har har!

Looks cool man, hope you enjoy it a lot with your new MS3

xsq said:

That vent looks a little overkill - har har har!

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Better overkill than underkill...if that makes any sense? :o