Need help..monitor appears to be dead

scamp

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So I have a Tron that was fully working until I went messing with the power supply...

I've put in a switchers and the game is playing headless...monitor has now glow....

Monitor is getting 120 to it...

The chassis is a Wells G 19k4906..

What should my next step be?

1. Discharge
2. Pull chassis and check fuse?

Anything else?? I'd love to get this working again if possible!!!

Thanks!!
 
Has the monitor been rebuilt ( i am guessing no). I would order a cap kit and rebuild it while you have it out. And ya, you need to check that fuse, but chances are if it's blown, another one will do the same.

edit: you sure you did not mess the boards up playing with the power supply. What exactly do you mean by "messed with the power supply"
 
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I hope you didn't remove the isolation transformer when you "put in a switchers"...
 
I think you think the thing at the bottom...no...but at one point I was tapping into the power wire for the monitor for the wires to the switcher and one of the wires were hanging down there and sparked.....I think that might have done whatever damage to cause the monitor to stop working...no glow etc...

I'm hoping its the fuse.....

I've already sent an email to Bob Roberts for a cap kit...

I hope it doesn't mean its just dead...it worked fine prior to all of this!!
 
Tapping into the power for the monitor was your first mistake. Take some pics of the setup and post them up. that way people can better help you.
 
I was just following the directions that come with the switcher adapter board from Arcadeshop...

I've done this in my Jungle King and it worked...

This was because the clips cut the wire too much...I've repaired the wire...

Pulled the chassis and the fuse is blown due to this...I'm in process of replacing...also a cap kit is coming in mail...but I'll probably try it after replacing the fuse and see if it works...
 
You may have blown the voltage regulator and a rectifying diode or two also...
 
The fuse did not bring it back to life....

So how do I determine if I need a new voltage regulator and rectifying diodes and such?

Also, does anyone have a pic of this chassis wired up? I tried to take pics as I removed the wires, but they did not come out good and I want to make sure things are wired correctly (they aren't molex type plugs that only fit one way!....

I'd like to order whatever I need to bring it back to life today...Ideally I'd like to get this thing working before the holiday weekend for family to play while here...
thx!
 
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The Bally/Midway Monitor Troubleshooting guide says: (pg 7 of pdf)

Monitor won't turn on:
A Problem in power supply. Check fuse (done, replaced), transistors, open fusible resistor
B. Shorted horizontal output transistor
c. Defective high voltage disabling circuit
D. crack in main chassis board

So can someone help walk me through how to test:

1. Transistors
2. Open Fusible Resistor (what is that?!?!?)
3. Check for shorted horizontal output transistor
4. Check for defective high voltage disabling circuit


Thanks!! much appreciated!
 
Okay here is what I learned....

I found a doc on the web by Randy Fromm titled VIDEO GAME MONITOR REPAIR Troubleshooting Horizontal Deflection Failures


The doc discusses the Horizontal Deflection Circuit. A critical component to it is the horizontal output transistor...This cross references from the Bally Guide telling me if the monitor won't turn on to check this component...

I followed Randy's description on how to test it, and it in fact seems to be shorted or dead....This was the main culprit as per Randy's doc for most problems and is typically associated with the Fuse being blown (which had happened to me)...

So with my fingers-crossed, I've placed an order for the part to arrive by Friday...I may have my cap kit by Friday as well...so HOPEFULLY...this will put me back in business!!!!

I hope this solves my problem and helps someone else out too!!
 
I replaced the horizontal output transistor and it still isn't working.....

I need help gang....I'm not sure what parts to replace at this point...

I have no idea which is the open fusible resistor.......

anybody have any ideas???

Anybody have a Wells 4906 they want to sell? ;-)
 
Tapping into the power for the monitor was your first mistake. Take some pics of the setup and post them up. that way people can better help you.

Still could use these.

at one point I was tapping into the power wire for the monitor for the wires to the switcher and one of the wires were hanging down there and sparked

Why were you doing this with either the power on, or the game plugged in?

So, when you meter the horizontal output transistor now, are you getting the same reading you were before?

How is the fuse now?
 
The game is getting power...it plays blind...sound everything...the problem is the monitor now...

Power is traveling through the monitor power cable, how do I know? Because I spliced in the power wires for the switching supply....

Pictures would just represent a Wells Gardner 4906 chassis....

I wasn't messing with it with the power on per-se...I had the 2 wires for switching power supply still attached to the monitor wire (hanging) when I tried to put the original power supply in....anyway, what's done is done...the real problem is the monitor....

Both the old horizontal transistor and the new get no reading when testing with the black lead on the chassis and the red once on the case of the transistor....The fuse is still fine since I've replaced it...
 
Meter set to Ohms, correct? That would indicate that both the old and the new horizontal output transistor are good. Open, or very high resistance generally means that it's good. There are exceptions, but they're rare.
 
Generally, meter set to DC voltage. Black lead to frame, red lead to either side of the large white resistor mounted on the frame. List both voltages at either side of this resistor.

This is kind of a pain in the butt on a K4900. There may be a better place to put the red lead, but I don't have one in front of me to give a suggestion.

Modesitt?
 
Do you mean this big blue-ish resistor?? (In my photo it's at the top of the pic)??

I attached a photo of the chassis
 

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  • 4906-chassis.jpg
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That large white rectangle is a resistor????

Is it a special kind? What is it's purpose in the chassis? Does it ever go bad?? I've seen these on the power board too...
 
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