Installing my first cap kit on a G07 / Joust

smokinfish

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So I want to take the plunge and install a cap kit. I ordered the kit from Bob Roberts, and soon I will be ready to go! I have watched videos online, and read as much as I can find. It sounds easy but there seems to be some scariness to it as well. I have discharged a monitor before, so I have that completed. But I have never dismantled a board from the monitor or handled a board / monitor tube on there own. That part does make me nervous, because you don't know until it happens. Any tips I should look out for?

Also I found this:
if you are installing the cap kit into a dead Electrohome GO7 monitor with a blown F901 fuse, be sure to short across the fuse as it will be storing a large painful charge.

If my monitor is working do I need to worry about this?

Why the need for a cap kit? ok here it goes but remember I am just learning! 1. the Joust monitor just doesn't seem as vibrant as my Robotron 2. the blacks seem dull this may be because the colors aren't as bright. 3. On the right side there seems to be about a inch of really dark pixels. 4. When I centered the picture up, (the previous owner shrunk it and moved it to the left so not use the dead pixels) I get a crazy line of multi colored pixels on the top of the screen.

I have played with the settings on the back of the monitor to get a better picture. The Robotron is just sooo much cleaner and brighter. I will say the joust monitor does have some serious burn in from multiple size settings. The Robo has minimal burn.

Any feedback, tips, or suggestions as always is appreciated.

Thanks
Mark
 

dont hold the soldering iron on for more than 6-7-8 seconds as the heat can damage transistors, chips, etc. you will get the hang of it quickly.

look for cold solder joints and resolder them too.

dont rely on the silkscreened mark for the orientation of the capacitors for reinstallation. very few mistakes are out there but you dont want to learn the hard way. i used to use an arrow pinned to a nearby shelf to point the direction of the negative lead so i wouldnt install one backwards.

cap kits generally dont come with the big huge cap so you might want to order them too for installation.

get a lamp with a magnifying glass.
i like the high tech solder from radio shack.
i use a big fan in the window in front of me as i dont want to die from breathing whatever gasses come off of the solder, etc.

i need an oscilliscope bad and am hoping someone here can sell me a working one.

good luck and have fun !
 
Well, since you did some reading, I hope you noticed the part about replacing the original flyback at the same time you replace the caps. If you don't, it's a good bet that the flyback will die sometime in the next month or two (possible immediately).

And no, you don't need to discharge the backside of the fuse if the monitor is currently working. If the fuse blows, then the filter cap doesn't discharge, and it will bite you a lot worse than the tube would if you didn't discharge it.

As for the colors, your caps will probably brighten them up, but don't be surprised after the cap kit to find everything a bit darker or brighter than you need. It's normal to have to make brightness or color adjustments after a cap kit.

If it's still not vibrant enough, you may need to have it rejuved, or the tube could just be tired or have too much burn in...
 
I get a crazy line of multi colored pixels on the top of the screen.

if you're referring to the line of rapidly flashing and changing colors, that's standard issue for many early Williams games. i've got the same on my Defender. you can either try to move them off screen by adjusting the vertical size and position or just live with it. why they're there is as far as i know a mystery to just about everybody.
 
I hope you noticed the part about replacing the original flyback at the same time you replace the caps. If you don't, it's a good bet that the flyback will die sometime in the next month or two (possible immediately).

Is this just for G07 monitors, or is it a best practice when re-capping any monitor?
 
Is this just for G07 monitors, or is it a best practice when re-capping any monitor?

G07's (and maybe K7000's) that have original flybacks. Others don't necessarily need to be replaced unless you have a problem with them....
 
On the cap kit install I wouldn't remove the monitor from the game. Just remove the chassis board and neck board. Before you put the chassis back in find the right size allen wrench that fits the inside of the horizontal output coil and make sure you can turn the iron core.(buying a plastic wrench is optimal but not necessary) After you get the monitor running again I would try to center the picture as best as possible using those centering tabs to get an equal amount of black on each side. Then with the power off, adjust the HOC core with the allen wrench to stretch the picture a little at a time. Stopping to turn the monitor back on to see the change in picture width. Make sure you take the allen wrench out each time before powering up if its metal. When the picture fills the whole width of the screen on both sides, then adjust the vertical height control to fill the top and bottom of the screen out or shrink it if need be.
 
On the cap kit install I wouldn't remove the monitor from the game. Just remove the chassis board and neck board. Before you put the chassis back in find the right size allen wrench that fits the inside of the horizontal output coil and make sure you can turn the iron core.(buying a plastic wrench is optimal but not necessary) After you get the monitor running again I would try to center the picture as best as possible using those centering tabs to get an equal amount of black on each side. Then with the power off, adjust the HOC core with the allen wrench to stretch the picture a little at a time. Stopping to turn the monitor back on to see the change in picture width. Make sure you take the allen wrench out each time before powering up if its metal. When the picture fills the whole width of the screen on both sides, then adjust the vertical height control to fill the top and bottom of the screen out or shrink it if need be.

nope nope nope, NEVER USE A STEEL TOOL ON THE WIDTH COIL. magnetic resonance will heat it up cherry red and quickly, it will also swell the ferrite core , freezing it in place. save yourself the headache , spend 6 bucks and get the proper adjusting tool set
 
if you're referring to the line of rapidly flashing and changing colors, that's standard issue for many early Williams games. i've got the same on my Defender. you can either try to move them off screen by adjusting the vertical size and position or just live with it. why they're there is as far as i know a mystery to just about everybody.

My understanding is that the cause is known - it's an error in the blanking code that misses the top line of the scan, so you get rainbow-hued random garbage just on that top line.

RussM
 
Space cowboy missed the part where I said don't put a metal allen wrench in the HWC while powered on. There is an added risk though of cracking the ferrite core if you torque to hard which is why you should get the proper fit and make sure the core adjusts freely out of the game where you can see it turn and be very careful. The horizontal width coil (HWC)at L503 I meant to say. When you get it out of the machine there should be a ferrite core that has a hexagonal hole in the middle of it. You are supposed to adjust it with a plastic allen wrench but they might be a pain to find nearby. As for the centering tabs, since you are going to do a cap kit you might want to wait on doing adjustments until after because the cap kit might just fix the problem. But if not, you have to start with the image centering so you can then accurately stretch the horizontal width to both left and right edges of the screen. That adjustment will automatically alter the vertical length of the image and should hopefully change it to the correct length for the screen. The vertical positioning of the image probably will be a little off either too far up or down. So just adjust the vertical position with I believe the pot at R408. If you adjust the vertical first you will be adjusting it based on the wrong aspect ratio. The horizontal stretching(or shrinking) done by the HWC adj.(L503) controls the aspect ratio between height and width.
 
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On the cap kit install I wouldn't remove the monitor from the game. Just remove the chassis board and neck board. Before you put the chassis back in find the right size allen wrench that fits the inside of the horizontal output coil and make sure you can turn the iron core.(buying a plastic wrench is optimal but not necessary) After you get the monitor running again I would try to center the picture as best as possible using those centering tabs to get an equal amount of black on each side. Then with the power off, adjust the HOC core with the allen wrench to stretch the picture a little at a time. Stopping to turn the monitor back on to see the change in picture width. Make sure you take the allen wrench out each time before powering up if its metal. When the picture fills the whole width of the screen on both sides, then adjust the vertical height control to fill the top and bottom of the screen out or shrink it if need be.

Space cowboy missed the part where I said don't put a metal allen wrench in the HWC while powered on. There is an added risk though of cracking the ferrite core if you torque to hard which is why you should get the proper fit and make sure the core adjusts freely out of the game where you can see it turn and be very careful. The horizontal width coil (HWC)at L503 I meant to say. When you get it out of the machine there should be a ferrite core that has a hexagonal hole in the middle of it. You are supposed to adjust it with a plastic allen wrench but they might be a pain to find nearby. As for the centering tabs, since you are going to do a cap kit you might want to wait on doing adjustments until after because the cap kit might just fix the problem. But if not, you have to start with the image centering so you can then accurately stretch the horizontal width to both left and right edges of the screen. That adjustment will automatically alter the vertical length of the image and should hopefully change it to the correct length for the screen. The vertical positioning of the image probably will be a little off either too far up or down. So just adjust the vertical position with I believe the pot at R408. If you adjust the vertical first you will be adjusting it based on the wrong aspect ratio. The horizontal stretching(or shrinking) done by the HWC adj.(L503) controls the aspect ratio between height and width.

Really? No seriously, Really?

Smokinfish, do the job right and pull the monitor as a whole. Install your cap kit, replace the monitor, and adjust the monitor as needed.

For your SAFETY, DO NOT use any kind of metal allen wrench when adjusting the Horizontal Width Coil.
 
Well, I wouldn't pull the entire monitor from a Joust, as it's very easy to access and remove the chassis without doing so. If you were doing one in a Pac-Man for your first one, then I'd probably recommend pulling the entire thing, as it can be difficult to get everything mounted and plugged in properly in a Pac-Man if you've never done it before...
 
Yes really. Why would you need to pull the monitor as a whole? To do the cap kit you have to remove the boards from the monitor chassis anyway. I see no need to take the picture tube and metal frame out of the cabinet. In fact I see it as an unneccesary risk. I'm not saying to skip safety procedures. Of course discharge the anode and disconnect the monitor boards and its connectors from the game. There is nothing unsafe about using a metal allen wrench when the power is off. You just have to be careful not to over torque the core when trying to turn it and of course don't leave it in there. If someone doesn't think they can manage a little finnesse, then they probably shouldn't mess with these things. If a metal allen wrench can't budge the core because its already trashed than the plastic one certainly won't get the job done. If it won't move, I don't force it, I go to plan B and change the value of the HWC's corresponding ceramic capacitor(on a WG4900). What am I missing? If I have somehow missed something you find obvious I honestly really would appreciate your input. But if they don't sell those plastic wrenches nearby, many people are not going to wait 2 weeks for them to come in the mail. I thought my posts were very detailed and clear and I mentioned the risk of over torqueing. Telling someone to "adjust the monitor as needed" is kind of vague and probably won't result in a "distortion free" monitor picture.
 
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Smokin, one thing I think maybe most people might agree with me on. Before you do the cap kit, you might want to identify the capacitors you will be replacing and their locations. Then, verify that there are no descrepancies between the polarity of the capacitors leads that are currently soldered into the holes of the board and the polarity markings stamped on the board. On rare occasion there can be revisions to a design that were not updated on the boards markings and it is important to catch that. And there might be one non polarized capacitor in the kit that can be soldered in any direction.
 
I did a cap kit on my G07 in my ms. pac-man about 6 months ago. i left the monitor in there and pulled out the board as some people have indicated. While ultimately my cap kit didn't help I do have 1 bit of advice for what its worth. Take your time, be patient and be careful. Heed all the appropriate warnings. ;)
 
I did a cap kit on my G07 in my ms. pac-man about 6 months ago. i left the monitor in there and pulled out the board as some people have indicated. While ultimately my cap kit didn't help I do have 1 bit of advice for what its worth. Take your time, be patient and be careful. Heed all the appropriate warnings. ;)




Well said.
And...a cap kit isn't the answer for every problem. And replacing an old flyback that shows no evidence of being defective just seems like a waste of money to me.
 
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