Tube Swap K4900 Question

[daxwell]

I'll pull it by the end of the week & PM you for your address when I'm ready to mail it.

 

[Oryk Zinyo]

I'll pull it by the end of the week & PM you for your address when I'm ready to mail it.

Thanks for doing this.

 

[daxwell]

Ok, so I start the tube swap. Pull the monitor from the game. Pull the rings and the yoke. Start to pull the rings from the donor tv and bam... the rings are attached to the yoke. Is this an unusual occurance, or am I just jinxed? Guess I'll be going back to the thrift stores.

 

[modessitt]

Ok, so I start the tube swap. Pull the monitor from the game. Pull the rings and the yoke. Start to pull the rings from the donor tv and bam... the rings are attached to the yoke. Is this an unusual occurance, or am I just jinxed? Guess I'll be going back to the thrift stores.

Is the yoke bonded? If not, just remove the yoke/ring combo and use the rings from the 4900.

I've seen a few monitors and TVs with the rings and the yoke all on the same plastic piece. The problem is if the yoke is bonded to the tube. If so, then you're screwed...

 

[daxwell]

Mod, the yoke isn't bonded. I had it in my hands. The rings and yoke are connected to each other. It is one piece of plastic. Isn't it much, much harder to get the new monitor aligned if I don't use the rings from the donor tube. Is it worth trying or is my best bet to get another CR-23 tube?

 

[modessitt]

If you mark the 4900 rings and measure the distance between the rings and yoke and rings and pins, and move them as one piece without moving them (or if you do, putting them back to the way you marked it) you'll have minimum convergence issues when you're done.

And there is a convergence walkthrough in the 4900 manual...

 

[Fudd]

for some reason the dozen tv's i have run across all have had the yoke and rings as one piece. i have yet to see one that was seperated.

 

[daxwell]

So I went ahead and did the swap with the K4900 yoke and rings. I', hoping now my problem is mostly degaussing. Here are some pics after the swap. The first pic is the old tube with Qbert and some other game burned in. The next three are of the new tube after the swap. I think that I have the yoke lined up correctly. The purity rings were glued (hot glue) in position, so they haven't individually moved. Rotating the whore ring assembly, and moving it up and down the neck doesn't seem to do much of anything.

Questions - 1) Is degaussing the main issue with the colors right now, and if so how can I fix it. I tried running my corded drill above the monitor but nothing happened. Does the monitor have to face a certain direction - I thought north, but I'm not sure.

2) Will I have to move the rings individually to correct the colors?

 

[Fudd]

Looks like your yoke is either too far or too close to the tube

 

[daxwell]

Thanks Fudd. I played with the yoke and now I have these pics. I think the yoke is correct now.

Just FYI, I have a problem with the red color. I thought it is was the red drive pot but now I'm not sure. When I started to do the convergence directions in the manual, and thankfully I don't think I need to, I turned down the drives so I only had Green/Blue or Red. When I had only red, only green appeared. When I shor the red pot, I get red on the screen. I will order new pots and transistors soon.

 

[daxwell]

I don't know what I'mdoing wrong with this tube swap. I'm trying to follow the directions in the manual by turning down the red and blue drives and trying to get a uniform green onthe screen. In order to do that I need to pull the yoke almost all the way off the neck. When the yoke is close, having just the green drive on gives me a blue screen. I haven't had any success in getting any 1 color 100% uniform. I was already grey, but I don't want to pull my hair out. I'm leaning towards buying an alva chassis since I have an extra 19"tv. I did however solve my missing red issue - bad connector from the jamma harness to the monitor chassis.