Semi-working k4600 dead after cap kit

hindered

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I have a k4600 that was working sometimes, if you nudged the cab it would wink out and exhibit other weird behavior. So I did a cap kit. In the process, I cut the neck board wire and the degaussing coil wires to have easier access to the main board. (as an aside, whoever says 20ezs are hard to work on is crazy.. the 4600 is a huge pain in my ass... why the HELL is it impossible to get the chassis out without cutting/desoldering a billion wires). I also accidentally ripped the two brown wires off from the width coil. The two purposefully cut wires are reconnected with molex, and I resoldered the pulled wires to the width coil.

Buttoned everything back up -- no power. No neck glow, no hv whine, no static, nothing. B+ is 0vdc.

Possible culprits -- does it matter which way the wires are attached to the width coil? Can it be wrong? Should I swap them?

One of the wires to the degaussing coil was pulled off from the weird place on the corner of the frame with the capacitor it was soldered to. I resoldered it, but may have gotten it in the wrong place.

Any other ideas? I doubt it's any of the stuff on Fromm's flowchart -- the monitor was getting raster and more or less working prior to the cap kit.
 
btw this chassis appears to be super hacked... lots of red jumpers on both sides of the chassis... the daughter boards have lots of caps and resistors on the solder side. is this normal?
 
The only wire that needs to be cut to remove a 4600 is the ground wire to the neckboard. Everything else will unplug or come with it. I usually unsolder the width coil wires (after marking one) instead of taking that out, too.

If you hooked up the width coil backwards, the coil should still work, but in the opposite position from previous.

Did you reflow all of the pins to the daughtercard?
 
The only wire that needs to be cut to remove a 4600 is the ground wire to the neckboard. Everything else will unplug or come with it. I usually unsolder the width coil wires (after marking one) instead of taking that out, too.

If you hooked up the width coil backwards, the coil should still work, but in the opposite position from previous.

Did you reflow all of the pins to the daughtercard?

There are two daughtercards, and I reflowed the pins to both. Neither the width coil nor the flyback are on the board and are mounted to the frame. I didn't want to deal with them hanging loose while working so I didn't dismount them. Also the degaussing coil is one example of something that would've had to be desoldered -- it runs to some weird location of parts (at least 1 capacitor, maybe other stuff too) in the corner of the frame before going to the board... where I believe it's soldered there too. I've never worked on a 4600 before so I'm not sure how much of this is normal and how much is unique to my monitor. It's pulled from a Rockola cab if it makes a difference.

EDIT: Just remembered, if by daughtercard you mean the one on the far edge of the PCB that has a bottlecap transistor on it -- I don't remember if I reflowed those or not. I'll give it a look when I get around to taking the chassis out again. I'll try to get some pics too.
 
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Well, excuse the criticism, but if you cut different wires rather than pull it all out because you didn't want to be inconvenienced, it's not surprising that it's not working now.

I guess you should start by going over everything you did and making sure it's all done properly. And since you didn't pull the flyback out with it, check that none of the wires from it to the chassis came loose. Make sure you plugged in the connector on top of the left daughtercard. Make sure the yoke connectors are on properly...
 
Well, excuse the criticism, but if you cut different wires rather than pull it all out because you didn't want to be inconvenienced, it's not surprising that it's not working now.

I appreciate the feedback, but it's not really fair. I purposely cut three wires and added molex connectors for easier removal before I realized just how many wires would have had to be cut. I could've probably undone the flyback and width coil at that point and removed the entire chassis, you're right. But the neckboard wire and the degaussing coil needed to be desoldered or cut. Now I'm wondering what's going on with my degaussing circuit because you say that shouldn't need to be undone.

modessitt said:
I guess you should start by going over everything you did and making sure it's all done properly. And since you didn't pull the flyback out with it, check that none of the wires from it to the chassis came loose. Make sure you plugged in the connector on top of the left daughtercard. Make sure the yoke connectors are on properly...

As far as "making sure it's done properly", this chassis is messed up, so it's hard to tell. I don't have a ton of experience, but I've worked on 3 sanyo monitors, 3 4900s, 2 g07s and a nanao ms9 and those were all relatively similar. This one is a different beast entirely. Do the hacks/jumpers/solder side parts/etc that I mentioned before sound standard for a 4600?

I'll double check the connector to the daughter card, and loose wires to the flyback, although I remember doing the connector, and I had inspected the flyback at that point too. With regards to specifically checking the polarity/placement of the caps I did, I checked and doublechecked as I went along. They're right.
 
BTW mod I didn't take offense at your criticism, and I hope you didn't at my reply. This chassis is a bit of a nusiance to work on though. I'll try to get those pics sometime soon, but right now all my free time is going towards refinishing floors. :(
 
The whole chassis comes out easily and only the black tube ground wire needs to be cut. Naturally you unplug the power cord and video signal cable from the monitor first.

Slide neckboard off of the tube.

Remove two 1/4" hex head screws that secure the main chassis assembly at the far left of it.

Remove the two 1/4" hex head screws securing the flyback to the side wall.

Disconnect the high voltage anode suction cup (after first discharging the tube).

Now the whole works comes right out so that you can work on it on the bench.
 
The whole chassis comes out easily and only the black tube ground wire needs to be cut. Naturally you unplug the power cord and video signal cable from the monitor first.

Slide neckboard off of the tube.

Remove two 1/4" hex head screws that secure the main chassis assembly at the far left of it.

Remove the two 1/4" hex head screws securing the flyback to the side wall.

Disconnect the high voltage anode suction cup (after first discharging the tube).

Now the whole works comes right out so that you can work on it on the bench.

Okay, I'll double check when I get a chance. The process I followed was NOT this easy. Either mine's non standard or I missed the obvious/easy way of doing things. Thanks for the step-by-step.
 
Ken's right. You have to do a little more to get the plate off the bottom of the chassis, that's where the width coil becomes a problem.

Check for bad solder joints in the power section. Something must be not making proper connection to not get any b+... also check what you did over on that little vertical board mounted to the side, if the cap is backwards or something it may not come on. You probably would have heard the bang though :)
 
Just remembered one other thing (still haven't had a chance to pull it out at home yet) -- the replacement pot for one of the daugther cards BR sent me only had two leads. I ran a wire from the metal body to where the center lead of the old pot went, becuase that's what the old pot's center lead was connected to on the pot itself. I completely forgot about this -- could it be the cause of the issue? If anything, I'd expect it to cause the monitor to act weird (I think it's the black level pot) but not to fail to power up entirely.
 
If it's the black level pot and it's not working, then you'd get no picture at all...
 
If it's the black level pot and it's not working, then you'd get no picture at all...

I am getting no picture at all, and no b+, etc. I doublechecked and don't see any loose wires or missing connections or reversed caps. Maybe one of you guys will spot something I don't -- Pics incoming.

BTW I'm not sure how the whole works comes out together unless you're saying to remove the whole part of the frame, metal and all.. I suppose that would work although the width coil is still an issue. What I did was flip the monitor up and remove the four screws that held the plastic pieces that secured the PCB to the metal frame and remove the chassis that way...
 

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More pics. It's kind of hard to see, but there's a prong on the flyback that doesn't have any wire attached to it... but it looks like nothing was ever there to begin with.
 

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OK here's the two pics of the weird assembly that is part of the degaussing coil circuit. One of the wires ripped out and I soldered it back where I think it should be. I've got the degaussing coil disconnected right now and it didn't make any difference.
 

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If you have 0v for B+, then you have an issue in the Power Supply section of the monitor. Have you replaced your VR? Fuse Ok?
 
If you have 0v for B+, then you have an issue in the Power Supply section of the monitor. Have you replaced your VR? Fuse Ok?

Have not replaced VR, fuse was fine last time I checked it (post cap-kit). Monitor was working/displaying an image prior to cap kit.
 
Errr, if you mean the bottlecap transistor on the left side of the frame, then yes. I did the complete cap kit as provided by Bob Roberts.
 
Last time I got a 4600 cap kit from Bob, it didn't include the VR or HOT. I guess that means you replaced the brightness pot on your interface board....
 
Last time I got a 4600 cap kit from Bob, it didn't include the VR or HOT. I guess that means you replaced the brightness pot on your interface board....

Yep. It included the VR but not the HOT, if I understand correctly. I also changed the pot, and asked questions about it in this thread, and posted a picture of it above.

EDIT: "the replacement pot for one of the daugther cards BR sent me only had two leads. I ran a wire from the metal body to where the center lead of the old pot went, becuase that's what the old pot's center lead was connected to on the pot itself. I completely forgot about this -- could it be the cause of the issue?" & http://forums.arcade-museum.com/attachment.php?attachmentid=49127&d=1286409659

DOUBLE EDIT: Oh yeah, the old VR had what looks like a resistor (but may be a diode) soldered between a couple of the leads. I left it in place. One of the many things that seems strange about this chassis. Should it be there or not?
 
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