19K4606 in my $110.00 Pacman,dead

[SaminVA]

Ok I just noticed something strange.
The 4600 monitor I am trying to fix only has 1 rectifier diode X601
The schematic shows 4 diodes X601, X602, X603, X604
My working K4600 in my Frogger has all 4 diodes.
So what should it be? Could someone removed 3 diodes and left one on the board or is their a version of the board that only uses 1 diode?
Below is a picture of the 4600 in my Pacman with 1 diode and a picture of the 4600 in my Frogger with all 4 diodes.
Which is right?
Could this be one of my problems?

 

[Oryk Zinyo]

I believe those diodes form a rectifier bridge. Where does the blue wire go? Maybe the rest of the circuit was relocated.

 

[SaminVA]

I believe those diodes form a rectifier bridge. Where does the blue wire go? Maybe the rest of the circuit was relocated.

Yes they are the rectifier bridge diodes. If you look at both pictures the blue wire is on both boards in the same place and goes to the white resistor mounted on the metal bracket on the back side of the board

 

[Dokert]

Not it. I just checked my 4600 and it only has the 1 diode at X601 and it works flawlessly.

 

[Oryk Zinyo]

Is the bridge somewhere else?

 

[SaminVA]

Not it. I just checked my 4600 and it only has the 1 diode at X601 and it works flawlessly.

Thanks, I guess that means the HV transformer is bad

 

[SaminVA]

Is the bridge somewhere else?

Looks like they have one verson with 4 diodes and one with 1 diode.

 

[Dokert]

It is rare, but it does happen.

 

[Oryk Zinyo]

It looks like Chad has replacement flybacks:

http://www.arcadecup.com/

 

[SaminVA]

It is rare, but it does happen.

Well I guess my only option would be to try the one from my working monitor. I dont supose their could be something on the board that would kill my good transformer.

 

[SaminVA]

It looks like Chad has replacement flybacks:

http://www.arcadecup.com/

Wow, I guess I should have sent it off to Chad or someone else to start with, but I was haveing so much fun pulling my hair out.

 

[Dokert]

I don't see the 4600 flys available on Chad's site.

 

[SaminVA]

It looks like Chad has replacement flybacks:

http://www.arcadecup.com/

Where did you see K4600 flybacks for sale on Chads site.
I didnt see it, maybe I am blind today
Guess I should email him

 

[Oryk Zinyo]

I don't see the 4600 flys available on Chad's site.

Where did you see K4600 flybacks for sale on Chads site.
I didnt see it, maybe I am blind today
Guess I should email him

You guys are right, I could have sworn that I saw 4600 and 4900 fly's there this morning but I am not seeing the 4600 now...

 

[SaminVA]

Just thought I would give an update on my K4600 from HELL as I now call it.
I took my working K4600 out of my Frogger, it needs a cap kit anyway but it does work and I tested the 3 plug in boards from my Pac man 4600 and they all work. So that leaves the main board,flyback,tube and yoke. I decided to take the working guts from the Frogger 4600 and install it in the Pac 4600 frame. I powered it up and I got a full screen raster on the Pac 4600 tube. I even pluged the Degausser coil back in. That means the tube and yoke is fine so that narrows it down to the main board or the flyback. So what should I do next. As I see it I have 2 options. Swap out just the flyback and if the Pac 4600 flyback is bad it will take out my HOT and I'll know it's bad or if it works then I'll know the problem is on the main board. Or I could leave the working flyback from the Forgger 4600 in and put the Pac 4600 main board back in with a new HOT and if it works I'll know the board is good and the Pac flyback is bad. If I try the main board with my good flyback I hope their's nothing on the board that could takeout my good flyback. Any suggestions
Thanks

 

[SaminVA]

Good news, The 4600 monitor from HELL is fixed.
I decided to put another new HOT in the main board and wire up the working flyback from the Frogger 4600.
Put it all back together and checked and double checked everything and applied power and I could hear the sweet sound of hi-Voltage. Walked around to the front and I had a full bright raster on the screen. Now that it's working and has been capped I think I'll just put it back in my Pac man and find another flyback for the Frogger. I did buy another 4600 from a member here but it's the same mount as the Pac so I could just swap everything over to the Frogger vertical mount frame. At least it's suppose to be working so should be an easy fix.
Thanks to all who helped out with all the suggestions.

 

[SaminVA]

I have a question for all the monitor experts out there.
I got this K4600 capped, replaced the flyback with a used one and installed it back into my Pacman cabinet.
I tested my Pac board in my Jamma cabinet with an adaptor. The board worked fine, great picture and sound.
I put it back in the Pac cabinet and although I get no sound, should be simple to track down, I do get a picture and can coin up and play a game. The problem is it appears the Convergence is off. I have not moved any of the convergence rings but I suppose someone could have before I got the game.
Looking at the pictures do you think it could be a problem with any of the monitor boards or is this always the Convergence rings needing adjusting?
Any tips or tricks and can it be done without a RGB generator for a test pattern just by looking at the Pacman screen wile adjusting the rings.
Thanks

 

[Oryk Zinyo]

You should be able to fix that by adjusting your colors. It looks like the red is bleeding. I use a test pattern to make these kind of adjustments, but sometimes after installing the game board some additional tweeking is needed.

 

[Peale]

Yes, you have a convergence issue. Put the game into rack test and you should get a crosshatch pattern, IIRC. Mark the rings before moving them with something you can remove pretty easily. Then start making adjustments. Once you get everything where you want it, mark it with something permanent.

 

[SaminVA]

Well you were right Peale
The convergence rings move freely so they could have been moved. I moved the 2nd and 3rd rings as I think the first one is purity so didn't want to mess with that yet. I have it much better, not perfect but I can live with it. Maybe I'll try and tweak it a little more later . Now I have to figure out the sound problem. The board has 16 volts and 5 volts so it has to be lost contact for the speaker wires on the edge connector, broken wire or a bad speaker. It will give me something to do tomorrow.
Oryk, probably needs a little color tweaking too.
Thanks for the help