Help: 4900 med res sync issue

avidgeek

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Chassis has been capped, powers up but I can't seem to get it to sync. I don't know much about this specific chassis but is there a trick to syncing it?

The RGBHV wires as they sit work on my other med res monitor but this monitor is squirly with picture. Should I attempt to combine the HV sync wires together?

THanks.

AG

http://www.flickr.com/photos/82339247@N00/5504008738/

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If it's been capped, while do some of the caps look new and some look old? That would seem to indicate that only a partial cap kit has been done. You should complete it, including the one on top of the small add-on board.

As for the sync, if it's composite sync, then you should remove the vertical, but if it's separate sync, then leave it as is. Did you reflow the video input pins? Not uncommon to get cold solder on the sync pins...
 
If it's been capped, while do some of the caps look new and some look old? That would seem to indicate that only a partial cap kit has been done. You should complete it, including the one on top of the small add-on board.

As for the sync, if it's composite sync, then you should remove the vertical, but if it's separate sync, then leave it as is. Did you reflow the video input pins? Not uncommon to get cold solder on the sync pins...

Okay Mod, thanks.

Does the lack of sync look like a standard res chassis on a med res monitor? I'm almost certain the chassis is correct (med res) for the tube.
 
The only versions that had that little board on the top left is the 4915 (19" med-res), 5501 (25" standard-res) and 5515 (25" med-res). There are a few ways to check to see which way it is, and a search here should find a few posts I've made about how to do it, but it's most likely the proper one...
 
Looks like you have a 4915 in a 720, correct?

If so, you can not combine the sync wires to make it work. You can connect up the monitor using negative comp sync by using the neg comp sync pin on the video header at the video board and making a new video connector for the monitor header.
 
The only versions that had that little board on the top left is the 4915 (19" med-res), 5501 (25" standard-res) and 5515 (25" med-res).

I guess its a 5515 (25" med res) because at C311 the cap is 10uF 160v.

I'll try capping the entire chassis and see if that changes anything. I doubt it will as that picture really looks like a sync problem.

Can a 4915 chassis run successfully with a 25" med res tube? Anyone try it?
 
Looks like you have a 4915 in a 720, correct?

If so, you can not combine the sync wires to make it work. You can connect up the monitor using negative comp sync by using the neg comp sync pin on the video header at the video board and making a new video connector for the monitor header.

It is a 720....not following you on the last part of your post. Any pics to explain what you mean?
 
720 originally had a video cable with two ends on the monitor side, one end was for positive individual sync which you have and the other end was for negative composite sync. Sometimes med res monitors like the neg comp sync better than the pos individual sync.
 
Did this issue ever get resolved? I'm trying the replace my k5515 with a 7500 and I appear to have a sync issue as well. Looking at the schematics on both chassis, it appears as if they are identically labeled, but I keep getting a rolling picture on the 7500 (something that can't be adjusted out).
 
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