G07-CBO not filling all the way to right side

Dervacumen

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Been this way since I got it. I recapped and upgraded it, but what causes the screen to not stretch out all the way to right side only? I can't seem to make any adjustment with the horiz. width coil. Looked at the topic on Bob's site about not filling all the way horizontal, but in this case it's only on one side.
The picture is blurry because of user error with the camera.
 

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Is that as far right as you can adjust it with the pot? Use one of the jumpers to move it over....
 
I must be missing something, or a previous owner installed pots where the jumpers would normally be. That said, when I adjust the pot (which is where the jumper would have been) I do see a noticeable effect - but the only thing that changes is the curl over at the top goes from the right to the center to the left. Here's a pic of my chassis.
I adjust the brownish red pot to change the horizontal center.
 

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As I fiddled with the width coil my tool got stuck and pulled the top plastic piece off the coil. Apparently the ferrite screw type thing that should be in there is long gone. Looks like I'll either play around with changing the width capacitor ala Bob Roberts hint or get a new coil.
I don't know of anything else I need from Bob right now so maybe I'll wait until I troubleshoot my other chassis. That's more of a challenge.
 
Hmmm, I have never seen that mod with the pots on there. I'm not monitor guru, maybe one of the gurus can chim in....but iif I were a bettin man, I'd say that is the source of your issue....if the variable resistance(ohm value) on that pot is outside range of what those jumper wire's resistance is....you could dial that pot all day and it would NEVER move the picture to the right position.....
 
Yeah, I think I'd cut those pots off. The problem is you're basically connecting all three of them together, when in the design, only one of the outside pins is connected to the center pin with the jumper. If you put the jumper on the center pin, it's connected to itself. So with the pot installed, you're tying all that shit together at the same time and probably changing some values in that circuit. Just cut it off with some snippers and it'll be as if you've got the center jumper connected. If that needs moved from there, you could solder one of the outside pins to the center pin. That's basically what he was trying to do with the pot, but the pot itself is connecting the two outside pins together, and even with the pot turned one way or the other, the center pin is still connected to the other pin by the value of the pot!

Or: Pot is bad
 
What you're saying makes sense. It like the person tried to put a switch on the jumper pins. I'll get rid of them, it's easy enough to solder a jumper in place and see if it makes a difference.
 
Yup, definately. And if he would have used a switch, it probably would have worked, because the switch wouldn't stay connected to both sides.
 
It's a good day.
I removed the pot, jumped to the right, adjusted the curl out and I've got a nice picture pretty close to the middle of my screen. Now I'll have to see if I can adjust the width. I know the slug is still in my width coil but when I was adjusting it before nothing of note was happening. Unfortunately, the top white part of my width coil often tuns when I turn the slug so I have to remove the housing and slug, move the slug and then put it back. A little tedious, but I'll see if it works...

On a side note, the vertical pot is still there. It seems to be set in the right spot though, so I hate to screw with it until I get the horizontal tuned in.
 
Yeah get rid of the pots....use a jumper or a switch if you want to get fancy.......
 
I don't have experience with the width coil. Or much of anything, really. But I do know that adjusting the width coil, even manually does nothing. Apparently there is supposed to be a screw of some sort in the bottom of the center plug that moves up and down in conjunction with the plug in the center of the coil. My coil is missing that screw. If indeed there is a screw or whatever at the end. Rats. If only I had a bad chassis laying around I could rob.
I can order a new one but I need to put together a larger parts list first.
Picture sure looks nice though.
 
Here's how a 'width coil' works. It's a plastic piece, with a bunch of wire wrapped around it. that's all it is. The wire has a resistance of like 1 ohm or 2 ohms. So, if there's no 'slug' inside the coil (the part you adjust) the horizontal deflection circuit has a huge 1 or 2 ohm resistor in it. The way it's wired into the circuit, if there's no slug at all, the picture is the widest it can possibly be.

The 'slug' is a little piece of ferrite or whatever. It's a certain size and length. If you screw the thing down into the middle of the width coil, it shorts the coil out. So now instead of having a 1ohm resistor, you have a dead short, so it's essentially like you connected the width coil together and got rid of it. This makes the picture as small as it can be. So for instance, if you have a width coil that's screwed up, you can actually solder together the two sides of the width coil with a jumper, that shorts it as 'narrow' as it can go. Keep in mind we're sometimes only talking about like an inch that it can adjust.

So. in your situation, you want the picture to be as wide as possible, because your screen is too narrow. IF your B+ is set correctly (120 or so, have you checked it?) then just turn the monitor off, and using your tool, completely remove the ferrite core from the width coil. That will make the coil as wide as it can possibly go, which undoutedly won't be too far since your pic is so narrow right now.

Check your B+ though, if it's low, the screen will be too small.
 
The B+ is at 120. I pulled out the horizontal width coil core and powered on without it. The picture doesn't fill the whole screen, about 1 1/2" blank on the left and 1/2" blank on all other sides. Looking at Randy's troubleshooting chart, the next step is to check X303 and X304, correct?
 
Finally got to replace X303 and X304. The picture is nicely centered, but even with the width coil removed it won't fill the screen, leaving about 1" on each side. When I put the width coil back in, no amount of adjustment does anything that I can tell. I have not yet fiddled with cap 515 as suggested by Bob Roberts. Any other ideas before I do that?
 
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