ThatArtGuy's Joust Cocktail Restoration

The only other component that would suspect is Q5 (7905). The other parts should have been replaced with the rebuild kit.

Looking at the pictures of your power supply, Q5 is twisted pretty bad; may be a broken leg?
 
Hooked up the board and checked the Isolation transformer this time. I am getting the following out of the top:

1 - 120v
4 - 120v
3 - 0.2v
6 - 0.2v

On the bottom (can't read point numbers) I am getting 3.4v and 3.2v and nothing on the other points.

I am thinking that the isolation transformer is bad. It is going to be fun finding a replacement.

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Input side (TOP)
Pin 1 120 AC input via the interlock switch
Pin 4 is connected to Pin 1 via the 12 pin molex
Pin 6 120 AC input via the power toggle
Pin 3 is connected to Pin 6 via the 12 pin molex


Output Side (BOTTOM)
Pins 7 & 8 120 AC isolated output for the monitor
Pins 9 & 10 20 VAC
Pins 11 & 12 should be around 9 VAC (Might be higher)
Pins 13 & 15 23 VAC
Pin 14 is the center tap for Pins 13 & 15 (Pins 13 & 14 and Pins 14 & 15 should read about 11 VAC)
 
So... tonight I asked myself, "Self? Should we restring the guitar, or work on the Joust machine?"
"Well, self, you have a good idea on what to do on the Joust machine."
"Not really, self, but we will try anyway."
I then broke out the soldering tools and went to work. The first thing I did was connect W2 and W3 jumpers on the power supply board.

01.jpg

After doing that, I looked under the board and pin 12 on where the board connects to the isolation transformer was suspect. So I reflowed it and pressed it gently back towards the board.

02.jpg

I turned on the machine, and got lights!

04.jpg05.jpg

I still wasn't getting anything from the ROM board, but when I tested the sound board, it was so loud that I thought I was going to jump through the roof. I took a chance an pressed down on the interboard cable. Then I got this:

06.jpg

Success! I moved the yoke until I was satisfied with how straight it was. There were still some RAM errors so I fiddled around some more and got it stable. I tried to go into settings, but odd things were happening in the menus. I finally figured out that the second player joystick is permanently pushing left. I will have to check that out later. As you can also see above, I have some degaussing to do. I tried to fix it, but I will probably need to move the machine before doing final degaussing.

08.jpg

I was also getting a little curl at the top of the display. Convergence could be better, but I don't think the rings I have will move without disintegrating.
 
So after running the machine for an hour, the roll at the top has become worse, but hasn't gone down further.

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During this process tonight, I noticed power issues and finally tracked it down to the plug side of the power cord.

Things left to do:

Inspect image curl
Fix player 2 controls
Repair power plug

Oh, and get a battery for the PCB.
 
The curl at the top is gone since some adjustments since last night. I still haven't picked up a 2032 battery for the board yet, so the last part is the Player 2 going left controls.

After research at work, I found that the PIA chip may be the culprit. However, after getting home, I checked by starting a new 2 player game and disconnected the control panel. The ostrich stopped moving. That means that it isnt a PIA chip, otherwise it would keep moving. I checked the wiring on the CP and it looks okay. I have another leaf switch, but I don't think the switch is the issue.

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Looking at the schematics, it looks like the W1 jumper on the I/O board is used only on the upright. I will most likely need to remove it. This should hopefully be the culprit. It is the jumper closest to the capacitor at the bottom of the board next to the cable.

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Check continuity between both wires and that metal base.

Are there insulators around run the machine screws?
 
Right here (circle is what caught my eye as being suspect)

This is the screw I was talking about.

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If the circle area is clear, Try removing one screw, then the other, checking if continuity changes after each one.


If there is continuity, you could try a straw or coffee stir cut to length and slipped over the threads to insulate the machine screw.
 
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