Which P.S.U. Replacement.

[CHRIS-F]

Hi Guys,

My Jamma cabinet has some interference on the monitor, I don't really use the machine because of it, someone told me a while back it could be the PSU, so I replaced the PSU electrolytic caps with what I believed to Panasonic low ESR caps but it never made any difference to the interference, also after I recapped it seems to vibrate a bit causing a weird noise on the PSU housing, is it possible the PSU could still have other problems?

As I said in another post I initially wanted to get rid of the CRT and fit a flatscreen, but after powering the machine on (after a few years of it gathering dust) and seeing how good the image was I decided I would like to try and get it running properly with the CRT.

I thought it would be a good idea to start off with a new power supply, but what should I look out for I've seen the terms Linear and Switching what is my old type (see attachment) and what type should I get as a replacement? Are there different amperages or were all games compatible with the same PSU, I intend to use MAME mostly in the future but I am currently running a city connection PCB and I would like to be able to swap over from MAME to a real PCB from time to time, also would it be ok to leave a PSU attached running with no PCB connected just the mars coin mech I would like to try and connect the coin mech via a relay so it works with MAME and PCB's to make swapping from one to the other a matter of swapping the harness from my j-pac to a pcb. edit forgot to mention I'm in the U.K.

Thanks in advance guys :-)

[Mike A]

What does the extra set of leads on the AC input connect to?

[Titchgamer]

Here ya go:

https://www.arcadeworlduk.com/products/Black-Arcade-JAMMA-Power-Supply.html

[opt2not]

The PSU isn't powering your monitor.  PSU's are there to power your game PCB.

Monitors get powered from the power center in your cabinet. There should be the power entry from your wall outlet, which goes to the power center "block" usually consisting of a Fuse, an EMI Filter, a distribution terminal that connects to an Isolation Transformer (the big heavy metal block), then connected to your PSU for running the boards.

What kind of interference are you getting on the monitor?  Could you post a picture?

[Mike A]

I am thinking those extra AC leads are going to the monitor. Could that be the problem?

[CHRIS-F]

What does the extra set of leads on the AC input connect to?

I've not seen inside many arcade machines, but assumed this was how they were all connected, the mains lead connects to the PSU and the other set of leads go to the isolation transformer (is that what it's called?)

[Mike A]

It should be something like this.

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[Mike A]

Does the AC main go straight to the PSU or is there an AC line filter before the PSU?

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[opt2not]

What does the extra set of leads on the AC input connect to?

I've not seen inside many arcade machines, but assumed this was how they were all connected, the mains lead connects to the PSU and the other set of leads go to the isolation transformer (is that what it's called?)

Let's see some pictures of this wiring.   It's really hard to help if we don't get the full description on how things are wired.

[CHRIS-F]

The PSU isn't powering your monitor.  PSU's are there to power your game PCB.

Monitors get powered from the power center in your cabinet. There should be the power entry from your wall outlet, which goes to the power center "block" usually consisting of a Fuse, an EMI Filter, a distribution terminal that connects to an Isolation Transformer (the big heavy metal block), then connected to your PSU for running the boards.

What kind of interference are you getting on the monitor?  Could you post a picture?

Here's a picture of the interference, the lines alternate left to right they roll slowly left then right sometimes they are almost vertical but mostly about 45 degrees.

[CHRIS-F]

Does the AC main go straight to the PSU or is there an AC line filter before the PSU?

Sent from my Pixel 3 using Tapatalk

This is how it's wired the power cord enters the cabinet and goes to the PSU the other wires come out of the PSU and feed the Transformer, this is the only machine I've seen inside and I thought it looked normal?

[opt2not]

Yeah, I've never seen this kind of wiring before. Normally the power entry goes to a fuse and EMI filter first.  Some folks say the EMI filter isn't completely necessary, but I've seen many cabinets with it and would rather be safer than sorry.

If I were you, I'd re-wire the way the power is set-up here, and build a proper power center that incorporates a fuse. 

I recently built a new power center for a test bench, while repairing a few monitors, it's really not that difficult to do and requires no soldering.  Just a bunch of crimping and cabling.

This guide is invaluable for doing so:
http://therealbobroberts.net/acwiring.html

In fact, feel free to peruse Bob's site, there are many articles that have incredible information for people new to working on cabinets.

[CHRIS-F]

Yeah, I've never seen this kind of wiring before. Normally the power entry goes to a fuse and EMI filter first.  Some folks say the EMI filter isn't completely necessary, but I've seen many cabinets with it and would rather be safer than sorry.

If I were you, I'd re-wire the way the power is set-up here, and build a proper power center that incorporates a fuse. 

Thank, will check that out :-)

[Titchgamer]

My cabs done like that to.

The reason being (I would guess) is that in the UK we have fused plugs unlike you guys so the cable is protected right from where it plugs into the wall.

I do have a filter on mine though.

But yeah on mine it goes fused plug, filter, PSU then on to the marquee light and possibly the monitor? Never bothered to trace the last set of cables :p

[CHRIS-F]

Does the AC main go straight to the PSU or is there an AC line filter before the PSU?

Sent from my Pixel 3 using Tapatalk

Are either of these filters the right type for an arcade cabinet? what amperage do they need to be, also what size (amps) fuse should I be using in my cabinet as someone mentioned in the U.K. we already have a fuse in the plug. so not sure I would need another.

I'm looking at that diagram and wondering why the power switch is after the filter, wouldn't it be better for isolation purposes to have the switch directly after the cable enters the cabinet? (I'm a total noob with electrics just wondering).

Regards,
Chris.

[Mike A]

The first one looks like what is commonly used.

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[Titchgamer]

You will probably find a 3A fuse will suffice in the plug.

[Mike A]

Yeah. None of my games draw more than that even on startup.

[Titchgamer]

Yeah the PSU is rated for about 1.5A then you have extras on top which rarely equate to anywhere close to 3A lol

[opt2not]

My cabs done like that to.

The reason being (I would guess) is that in the UK we have fused plugs unlike you guys so the cable is protected right from where it plugs into the wall.

Interesting, I didn't know that about the UK.

Are either of these filters the right type for an arcade cabinet? what amperage do they need to be, also what size (amps) fuse should I be using in my cabinet as someone mentioned in the U.K. we already have a fuse in the plug. so not sure I would need another.

This is the one I use:
http://www.arcadeshop.com/i/1347/a.c.-power-line-filter.htm

3 Amp is what you need.

I'm looking at that diagram and wondering why the power switch is after the filter, wouldn't it be better for isolation purposes to have the switch directly after the cable enters the cabinet? (I'm a total noob with electrics just wondering).

Regards,
Chris.

Probably something to do with the EMI filter and the fuse not receiving any "spikes" when the power is cut.  But bobroberts is the man when it comes to arcade tech, he's been around for decades supporting the scene, so you can trust what he says is the gold standard.

[CHRIS-F]

Thanks for the info Guys :-)