adjusting screen on k7000a/k7000 swap

Hrvat9

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I picked up an Atari cabinet with the aero fighters kit in it. Not sure if it's the original monitor but the tube says zenith A48ACB02X. Anyways , the chassis has a power plug type of connector for the power to chassis while the harness has a molex connector. Can I cut the plug and put a molex plug instead to power up the monitor ? Assuming white goes to grey and black goes to brown
 

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Can you tell if somebody added that power plug to the chassis? I've never seen one with that on it like that, I believe you have a K7000a monitor, it usually just has a typical molex plug.

Just make sure that molex power is coming from the isolation transformer, if you plug the monitor into just regular wall voltage it'll blow up a bunch of stuff. It should be, but it looks like somebody's been in there rewiring things...
 
Can you tell if somebody added that power plug to the chassis? I've never seen one with that on it like that, I believe you have a K7000a monitor, it usually just has a typical molex plug.

Just make sure that molex power is coming from the isolation transformer, if you plug the monitor into just regular wall voltage it'll blow up a bunch of stuff. It should be, but it looks like somebody's been in there rewiring things...

it looks like it was suppose to be there, it goes straight to the fuse side of the board. And yes the molex comes from the ISO transformer. I'll give it a go today and see what happens.
Is it white to grey and black to brown though ?
 
Just did it , black to brown and white to grey and it blows the fuse right away. Read up somewhere that this could be the flyback which are obsolete for the k700a.. going over the board now looking for shorts
 
Just did it , black to brown and white to grey and it blows the fuse right away. Read up somewhere that this could be the flyback which are obsolete for the k700a.. going over the board now looking for shorts

you should post a better picture because i don't think you have a k7000a.
 
you should post a better picture because i don't think you have a k7000a.

Here! How often do those big caps go bad? The one in the top left, I can push the top in like its swollen or something ? Also how do you test a flyback?
 

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Picture here. Just tested the diodes beside it and d20 is shorted in circuit and d21 also. Pulled both and d21 is good but d20 is toast.
 

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Yep, that's a k7000A. Testing flybacks uses a special type of tool, that runs some big $$$, there are other cheaper ways of finding out if it works or not. You're doing the smart thing, checking other components. Before all else though, I would confirm where exactly that brown and grey wires run to, just peace of mind.

Pull the HOT and test it, check the caps and diodes in front, and behind the flyback. Also, redo any solder on any of the bigger resistors & connector pins. If the fuse is blowing, start following the path before and after it. Others more experienced with the K7000A, please chime in.
 
Yep, that's a k7000A. Testing flybacks uses a special type of tool, that runs some big $$$, there are other cheaper ways of finding out if it works or not. You're doing the smart thing, checking other components. Before all else though, I would confirm where exactly that brown and grey wires run to, just peace of mind.

Pull the HOT and test it, check the caps and diodes in front, and behind the flyback. Also, redo any solder on any of the bigger resistors & connector pins. If the fuse is blowing, start following the path before and after it. Others more experienced with the K7000A, please chime in.

It's some sort of ring test I think I read up somewhere ? But is there a way to see if the flyback is shorted with a multimeter? I followed the brown and grey wires and it goes down to the ISO. I doubled checked to make sure so I don't fudge anything else up on the chassis lol the HOT on this chassis has 5 legs correct? And the vr has three, that checked out to be good. Checked the board for cold solder points and the connector pin for vid sync and rgb were all cracked, touched them up. I'll keep looking
 
if you have a diode shorted than that could be a fuse popping cause. like sterling said test the diodes (with one leg lifted out of circuit) and the HOT, VR and cap it. the flybacks on the k7000a rarely go bad unlike the WGk7000. do you have any history on this chassis?
 
if you have a diode shorted than that could be a fuse popping cause. like sterling said test the diodes (with one leg lifted out of circuit) and the HOT, VR and cap it. the flybacks on the k7000a rarely go bad unlike the WGk7000. do you have any history on this chassis?



Will do! Unfortunately no..it was In a storage bin where these guys worked on cars. Full of brake or metal dust inside the cab. One day the monitor "popped" the guy said. He didn't seem too knowledgeable about the arcades so I doubt it actually popped. The fuse was blown when I bought it though, first thing I checked. That's probably what he meant by popped. No black or burnt spots anywhere on the chassis so the flyback didn't arc to ground im assuming. Maybe just shorted out
 
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What's this thing ? it's shorted (pulled a leg) and looks like burnt on the paper that was surrounding it. THe white block beside it is also shorted (r104 , with leg pulled). r103 shorted
 

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Yeap, looks like the fly took the piss and took out a bunch of stuff

Anyone have a wells k7000 chassis and neckboard I can swap for this? I wanna do some arcading already :mad:
 

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Yeap, looks like the fly took the piss and took out a bunch of stuff

Anyone have a wells k7000 chassis and neckboard I can swap for this? I wanna do some arcading already :mad:

Make sure you can run a K7000 on your K7000A tube, don't forget to specify! (Unless they're compatible :) )
 
Ok , got a k7000 in it now with a p448 neckboard (10 pin) and were up and running ! The screen was jumping or scrolling I guess but I got it to stop and adjusted clearly, but this is as big of a picture as I can get. As you can see there's lots of room around the whole screen to be filled up. 50/60 pot is turned all the way too to get it where it is now so the picture doesn't fold/get squished. Any suggestions? Also on the left side it looks like that's the end of the picture while the right side looks to be cut off, like I'm missing picture there. Maybe it's just me ?
 

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What's this thing ? it's shorted (pulled a leg) and looks like burnt on the paper that was surrounding it. THe white block beside it is also shorted (r104 , with leg pulled). r103 shorted

None of those are shorted, just low ohm values. Just because the meter beeps doesn't mean there is a short.
 
Try adjusting the width coil and vertical height or size pot.

Totally forgot about the width coil! Vertical though that's as much as it will go :/
I will have at it after work and report back
 
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