WG 19K4900 Vertical Size problem (pic)

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New caps on the chassis (and a successful Tube swap. Woot!), but when I adjust the Vert Size pot, I get separation on the image.

Any ideas about what needs fixing?

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Yes. Chassis, Yoke, and Rings.
This chassis had vert issues even after the Cap Kit, and Before the tube swap. Just not separation like this.

Could it be that the yoke needs to be slid back a bit?
 
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Ifyou want to move the image upwards, you need to hit the horizontal pot(s).

concerning the separation, it looks like a sync issue. Maybe a wire became disconnected from the molex.
 
Ifyou want to move the image upwards, you need to hit the horizontal pot(s).

concerning the separation, it looks like a sync issue. Maybe a wire became disconnected from the molex.


This is the best I could adjust it. Any more Vertical adjustment and it starts to separate. Even at this point, the lines start to widen at the edge.

The chassis is the earlier model without the V. Dampener pot.

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For the older 3 pot chassis, male sure C313 is 47uF/160V and C308 is 3.3uF/50V. Most cap kits come with 100uF and 2.2uF caps (for the 4 and 5 pot chassis revisions), respectively, and those values will cause this issue.
 
For the older 3 pot chassis, make sure C313 is 47uF/160V and C308 is 3.3uF/50V. Most cap kits come with 100uF and 2.2uF caps (for the 4 and 5 pot chassis revisions), respectively, and those values will cause this issue.

I will order the 3.3uF and give that a try (I did put a 2.2 in there). I had a 47uF for 313, so that one is the correct value.
 
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I will order the 3.3uF and give that a try (I did put a 2.2 in there). I had a 47uF for 313, so that one is the correct value.

Hmm, I'm not sure if the 3.3uF will make much of a difference if you already have the 47uF in (I switched both out at the same time). You do have the properly matched yoke for the 3 pot chassis?
 
Hmm, I'm not sure if the 3.3uF will make much of a difference if you already have the 47uF in (I switched both out at the same time). You do have the properly matched yoke for the 3 pot chassis?

I swapped a new tube into an existing frame/chassis/yoke/rings, so it would have to have been mismatched prior to me acquiring it.
I do have another monitor with the 4pot chassis. I'll check the yoke for differences.

The large cap wasn't replaced when I did the rest of the caps. Would that make a difference?
 
it looks like the wrong yoke for that chassis, two different yokes for the 4900 which are not interchangeable.
 
it looks like the wrong yoke for that chassis, two different yokes for the 4900 which are not interchangeable.

I've got a 2021111208 on the 3-pot monitor, and a 2021111201 on the 4-pot monitor. Is that correct?
 
The -201 goes with the older 3 pot chassis.

Well, lesson learned. Never cap a 2nd (similar) chassis at the while in the middle of a tube swap.
Looking back, I think I put the wrong one in. I'll swap them & give an update.

Thanks!
 
Yet another lesson learned.
• 4/5 pot K4900 chassis uses an insulator on IC501.
• 3 pot K4900 chassis DOES NOT.

I swapped IC501 to see if that was why (4pot) chassis was outputting 150v at R503. I noticed that (4pot) had a mica insulator and (3pot) didn't. I left the insulator on the (4pot) chassis, but still got 150v @ R503. I thought maybe the person before me had placed it there in error, so I pulled it. F501 went up as soon as I powered it on.

The (3pot) chassis is still running fine with the IC501 that was swapped from the (4pot) chassis, without insulation.
 
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