Iso or not?

pacman71

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I pulled a polo monitor out of a Street fighter II. I am replacing it with a monitor that needs to have a iso transformer.

I don't see one in the cabinet, but does that mean that it doesn't have one? I see a pretty large power supply; could it be hidden in there?

I am not hooking this up until I know for sure...

Is there any way to test to see if the power is safe to use? I have a decent multimeter, but don't know how to test.
 
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Check to see if there is a large, isolation transformer shaped object bolted to the bottom of the cabinet. If so, you have an isolation transformer.

Or, the definitive way, unplug the game, and check for continuity between the blades of the plug on the power cord and the pins in the monitor's power connector. If there is continuity at all, then there's no isolation transformer.

-Ian
 
Check to see if there is a large, isolation transformer shaped object bolted to the bottom of the cabinet. If so, you have an isolation transformer.

-Ian

This should be made a sticky on how to spot and recognise isolation transformers!

Retrohacker said:
Or, the definitive way, unplug the game, and check for continuity between the blades of the plug on the power cord and the pins in the monitor's power connector. If there is continuity at all, then there's no isolation transformer.

-Ian
Now that's some good stuff right there. I'm going to try this out when I get home and if it works, you sir, shall be my hero for the day.
 
This should be made a sticky on how to spot and recognise isolation transformers!

Well, that's a start anyways....don't want to misconstrued a basic "power" transformer with an "isolation" transformer.
So I'd say that should be STEP 1.

Now that's some good stuff right there. I'm going to try this out when I get home and if it works, you sir, shall be my hero for the day.

And this should be STEP 2 because it is definitive.

Beings this game is Street Fighter II, which is most likely a kit, the OP should identify what cabinet it's in and that may help knowing what the original wiring layout should have been.
 
I am 99% sure there there isn't an iso in there . ISO's have never been incorporated into power supplies have they?

Thanks for the help.
 
ISO's have never been incorporated into power supplies have they?

Well, depends on what you're talking about. A switching power supply will NOT have an isolation transformer built in. A linear power supply, using a power transformer, sometimes uses only one large transformer to do feed both the power supply regulator board and the monitor. Examples here would be Atari games, with the large "power brick" assembly in the bottom of the game. This has separate windings for the low voltage for the ARII board, as well as windings that act as the isolation transformer. Similarly, Sega games tend to have a very similar setup - with one large transformer for everything. Another good example would be Williams games like Robotron or Stargate.

Games like Pac-Man have two transformers - one for the low voltage to the game board, one for the isolation transformer. Jamma games tend to have a standalone isolation transformer (or, perhaps, an isolation transformer with an additional winding for the coin door lights) and a switching power supply.

Also, it's important to understand the difference between a power supply and a power transformer. A power transformer is only a single component of a DC power supply.

-Ian
 
Dynamo cabs like that usually have the iso mounted at the rear of the cab not the bottom. Pull the drawer out and look inside the cab to see if it's not mounted in the back.
 
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