Is this an isolation transformer?

[rob1234]

I bought an isolation transformer to connect to a monitor I just bought, then when I pulled the power supply out of my cab, I noticed it ran to this silver box. Is this an isolation transformer, or what is it?

[MonitorGuru]

THe silver box is merely a power line filter. (basically a couple of capacitors to filter out RF noise).

However the power supply as you called it behind it *may* be an isolation transformer, you have to check what the markings are on it and where the wires lead to. We'd need more picturs to be able to tell for sure.

[rob1234]

more pics

[Ken Layton]

You have a power chassis assembly from a Williams cabinet. The silver box is indeed a power line noise filter. The big power transformer next to it already has an isolated winding for the monitor. Terminals 9 (purple wire with yellow tracer) and terminal 10 (also a purple wire with a yellow tracer) are the isolated 120 volt ac output to your monitor.

A Williams Defender manual/schematic set will match the wiring that you have.

[MonitorGuru]

Dang, if it wern't for the cost of shipping, I'd gladly send you a plain, brand new isolation *only* transformer (only 2 wires in, 2 wires out needed) in exchange for the entire power board and wiring that you have (that you won't need if you're converting the Defender to a Mame or newer game)- --- As I have a Defender that is a bubble bobble and I'm trying to convert back to original Defender-ness!  You wouldn't happen to live in ND/MN

[rob1234]

nope, I live in Kentucky. I have a plain old isolation transformer with 2 inputs and 2 ouputs, but can't figure out how to hook it up. I looked at the bob roberts ac wiring diagram and still can't completely figure it out. That is why I was planning on this one. A little off topic, but were these power supplies used in a select few cabinets? My cabinet is converted to a tecmo ninja gaiden, and I have no idea what it was. Here are a few pics, let me know if you have any idea what it is

[rob1234]

so if I connect the two purple and yellow wires to the monitor, that is all I need to power up the monitor? I am wirring an electrohome g07 monitor for mame use.

[rchadd]

I also need to hook up a MTC9000 monitor to an isolation transformer i managed to pick up.

I assumed that mains connects to input side of transformer and output hooks up to the monitor.

After reading the above I am wondering if a line filter also required?

[MonitorGuru]

Your cabinet is a Williams cabinet. It appears to have been a Robotron in it's past life. (It has a smaller chance of being: Bubbles, Sinistar, Joust, Moon Patrol). It definitely wasn't a Defender. I think it's a robotron due to the extra amount of panels on the side that stick out over the cross piece, but it's dark and I can't tell for sure.

In any case, an isolation transformer is easy to connect. One pair of wires should be labeled "Primary" (usually the two on the bottom) and one pair should be labeled "Secondary" (usually the pair on the top).  Just connect the primary to the neutral and hot AC wire, and then the secondary to the monitor... It's that simple.  (Test with a digital multi meter set at 200 Volts AC to ensure you have them connected correctly)..

Yes, you SHOULD use a AC line filter to prevent interference from making it into the game (both into the monitor and into game boards/etc..) Computer power supplies have them built in, but games need the separate box. Wire it up just like Bob Roberts diagram.

You can steal AC line filters out of the backs of many dead consumer devices like VCRs, old AT/ATX computer supplies (they're often attached directly on the receptical end of the power cord in the power supply--look for a black receptical and a couple, typically blue colored, round flat capacitors.... just use the whole thing and make your game have a detachable cord then!