nba jam TE/ WG 25k7191 problem

[neon]

I'm trying to diagnose a Wells Gardner 25k7191 that was found in an NBA Jam TE machine.  The machine powers up and I get sound but I don't get power from the monitor (plays blind).  Instead, the front fuse blows.

Having very little background on this type of thing, I was hoping you guys might be able to help out.  Initially, I found what I think is the the VERT sync wire that runs from the PCB to the monitor, but is unfortunately disconnected from the connector on the chasis board.  Additionally, the schematics for the 7191 list both +vsync, -vsync, and an additional ground, but no wiring is present on the NBA PCB for two v syncs.  It looks as if the connector has been broken making me think this isn't the original monitor or the previous owner hacked it up pretty badly.  I have taken a picture of it in case someone can recognize it as being wrong. 

http://nicholascrumrine.net/otherpics/arcade/connector.jpg


Having read a few threads now, I can't determine if a v-sync not being hooked up would blow the fuse.  I have noticed a few capacitors with clear, almost epoxy looking, goo running down the sides, and another with black mystery stuff at the base.  Here are best pictures I can get while the monitor is still mounted.  Does this look right?

http://nicholascrumrine.net/otherpics/arcade/leakycap2.jpg
http://nicholascrumrine.net/otherpics/arcade/leakycap1.jpg

The black and white wires coming from the monitor are zip tied to a green ground wire and is cut off before it reaches the chasis board.  Would this indicate that it wasn't needed?  Heres a picture.

http://nicholascrumrine.net/otherpics/arcade/noground.jpg

Finally, what is a good place in or around Austin, Texas that might be able to take a look at it? 

Absolutely any help would be greatly appreciated.

[Ken Layton]

First: NBA Jam generates composite negative sync and your video connector appears to be wired correctly (negative horiz sync).

Second: That is the two different types of glue Wells-Gardner used to secure larger capacitors from breaking free/vibrating loose/falling off during shipment. Over time and heat, the glue may discolor. Remember they ship monitors all over the world and under less than ideal conditions.

Third: NBA Jam dedicated cabinets were originally supplied with Wells-Gardner U-2000 and U-5000 monitors which did not need isolation transformers. It appears somebody did swap out complete monitors in your cabinet and cut off the original connector on the 7191. The 7191 DOES REQUIRE use of an isolation transformer or else damage will occur to the monitor, game power supply, or worse, the gameboard.

[neon]

Hey Ken!  Thanks for the quick reply.  I had seen you helping another person with a similar problem.  Glad youre still around.  Ok, so I understand I need the -H Sync running to the pcb but would that make my chassis fuse blow?  Im inclined to think that without it, I would just get a bad picture. 

[Ken Layton]

This monitor needs to be run from an isolation transformer. If run without one you'll blow the fuse and/or have other damage.

[neon]

http://nicholascrumrine.net/otherpics/arcade/isotrans.jpg

I'm pretty sure the isolated transformer is the device on the right?  If so it looks like both the load and neutral are running to the monitor, but are both split to the power supply on the left.  How does everything look?

[Ken Layton]

Oh so you have a dedicated NBA cabinet. You should have said so first because I thought you had a conversion kit cabinet. It makes a difference.

As I've said several times in the past regarding dedicated Midway/Williams cabinets (Mortal Kombat, Blitz, NBA, etc.), Williams ---fouled up beyond all recognition--- up the wiring to the monitor and connected the monitor power, fluorescent marquee light power, game switching regulator power supply, and (where applicable) dollar bill acceptor power all to the output of an isolation transformer thus defeating it's purpose.

This wouldn't matter if using a monitor that does not need an isolation transformer like a U-2000, U-5000, k7400, or k7500. However, the k7000 (or in your case 7191) DOES REQUIRE A CORRECTLY WIRED ISOLATION TRANSFORMER TO WORK PROPERLY AND SAFELY!

You need to either replace that monitor with one that doesn't need isolation or else you need to rewire the AC power wiring in the cabinet to ONLY have the monitor running from the output of the isolation transformer. That means the fluorescent light, game switching power supply, and (if applicable) the dollar bill acceptor power must be wired in BEFORE the power transformer in the circuit.

The way your cabinet is wired now, your monitor may already be damaged and that's why the monitor fuse is blowing.

[neon]

Sounds like I need to rewire it either way.  How would I go about doing that?  I'm assuming the power supply takes 110-120 volt.  Can I just split the power from the wall before the isolation transformer, run one to the power supply, and the other to the isolation transformer.  I probably need to cut the black and the white wires running from the chassis PCB board to the power supply, and also disconnect the wires running from the isolation transformer to the top of the cabinet (to the sound, light, etc).  I would then need to power the top of the cabinet, right?  Am I anywhere close?  Thanks!