g07 width issue

p1899m

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I've got a g07 in a jungle king cab. image never filled the screen so I did a width cap mod as suggested by Bob roberts. This was a while back and I recall that it helped but didn't get the image to fill the screen 100%. Based on what Bob says i wasn't sure how far I could go with the cap values and not cause issues. Talking with another KLOVer I was told I should be able to try a lower or higher value depending on what was needed and it should be safe. Pretty sure I had a .22uf 250 v mylar cap in there and the plan was to try a.1uf 250v cap and see if that made the image larger. In theory it should since moving from the larger original value down to the .22 increased the image size. Any how when I fired it up with the .1uf cap in there I saw a tiny flash on the chassis and the image on screen is now missing a couple inches off both the left and right sides of the screen. . I know the general area but not the specific component that the flash came from. I also smelled a light electrical burn but can see no obvious burn. I'm thinking I may have actually killed a cap although I'm not certain. The chassis has been recapped so if it was a cap it was a new one. Just looking for some insight. Could I have killed a cap? Or is there another more likely component that went bad?
 
In general, you should look for cold solder joints. If you recapped it with a full kit either from Bob Roberts or Zanen Electronics, even new capacitors can fail suddenly or for no reason.

Remove the width cap you installed in C515 and test it to see if it shorted.
 
In general, you should look for cold solder joints. If you recapped it with a full kit either from Bob Roberts or Zanen Electronics, even new capacitors can fail suddenly or for no reason.

Remove the width cap you installed in C515 and test it to see if it shorted.

The monitor was working fine with the new caps as well as with a different width cap for some time. After I had the initial issue swapping the width cap I put the other width cap back in place. I get the same results on screen with this width cap. Although not certain my educated guess is that the current width cap is good. Which would mean that something else is bad. I think I'm gonna try replacing a couple other caps in the area I saw the flash and see if I get lucky.
 
If you didn't solve this issue yet, or if someone else has a similar issue, I just fixed a chassis with a similar problem:

Monitor had been recapped with new flyback and new width coil. Had a good picture, but the image was too narrow (about 2" of black on each side). Tried replacing C515 horizontal width cap with a smaller value, and had a good wide pic for a bit, then smelled something burning and the image went back to the same narrower pic.

Upon inspection, I found a few issues:

- Cold solder joint on L502. Repaired and retested but still had narrow pic.
- Found R525 looked burnt, even though the value still measured as good. Checked D507 which is parallel with it, and found the value about half what it should be. Replaced both, and have my full picture again - and it's staying that way.

Just in case it helps someone...
 
Ok mod has been helping me via pm with this type of issue tonight (thank you )

I have a question or two.

I pulled the horizontal width cap (g07) position C515.

Replaced it with 2 mylar caps twisted together. VAlues of .033, and .068, giving me in the neighborhood of the .1 that is recommended for this procedure. (I think)

anyway, I went for it, plugged her back in, and I think the pic is a little better though I am not certain. I may have seen a little flash as power up (like Dan), and I have an ozone smell, or burning smell, but the monitor was working fine.

1. did I calculate the values right to drop into C515
2. should I try it on another chassis I have that definitely has 1-2" of black on either side of the screen (horizontal mode, in my wacko)? That way I could see if there is a difference.

open to suggestions
 
So I got some of the mylar caps and replaced C515 with a .1 uf cap.

I got a waaaaay too wide picture for a few seconds, then it settled down to being a little weird, but almost how it was. Well go to the back of hte cab and I smell smoke.

R525 and D504 are FRIED!

Fortunately I ordered several replacements for R525 and D504.

Should I just reload and try again? (R525 and D504)
 
Where did you get the .1uf cap. Is it a mylar 200v cap?

yeah it's from bob roberts width cap kit. 250v cap I think. I would need to go look, but the website says 250v.


keeping in mind this chassis worked great with a full rebuild, but picture was too narrow (horizontal mount)
 
Not sure if I mentioned it, but I did replace C515 on another chassis as well, and it made the picture almost full. I have maybe 1/2 " on each side of the screen now. So it was a success on one. This particular one is the one I did the stu pid experiment on with 2 green mylar caps twisted together the other day. (with too low of a voltage value rating)

I did not yet replace the diode or resistor on this one, but I don't think I will since the picture is so close to perfect now.


It's just the 2nd chassis that I mentioned in the above 2 posts that I have an issue with now. Again, it was 100% working with a narrow pic, so I replaced C515 with a .1Uf mylar 250v cap. and the diode and resistor burnt.

Is it worth just replacing them and firing it up again? I don't mind frying those parts again for a test.
 
ok well using the .1uf from bob roberts in C515 continually was burning up the resistor at R525 and the diode at D504. Well it happened the first time, the 2nd time after I replaced them, I turned the game off as soon as I saw smoke so it didn't actually burn them up the 2nd time.

Put the old .53 cap (or whatever it was) back in C515 now I have a perfect picture that fills the screen.

So is this a bad cap? (it's not shorted)
bad combination of parts?
 
ok, I am coming to realize that I should have been replacing d507 not d504.
going to change that and report back.
 
well on one of the 3 chassis I've been 'experimenting' with, I now have a blown flyback (I think)


plug her in, hear raster sounds, neck glow, no picture. yellow goo on the top of hte flyback. It's a new one.


could this mistake blow a flyback?
 
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