Tube Swap #2, should I do it?

Vongoosewink

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OK dudes, I'm ready for another tube swap on one of my many grubby monitors.

I've got a WG K7901 that I got from my recent 'Carnival Raid', it has bad 'cherry master' burn in it. Here are it's yoke readings:

2.2 Horizontal
6.4 Vertical

I have a Zenith TV with a compatible neck pin arrangement (9 pins in a hemisphere, and one 'key' pin). Here are it's yoke readings:

3 Horizontal
8.2 Vertical

What do the monitor gurus think? Are these yoke readings close enough to try?
 
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OK dudes, I'm ready for another tube swap on one of my many grubby monitors.

I've got a WG K7901 that I got from my recent 'Carnival Raid', it has bad 'cherry master' burn in it. Here are it's yoke readings:

2.2 Horizontal
6.4 Vertical

I have a Zenith TV with a compatible neck pin arrangement (9 pins in a hemisphere, and one 'key' pin). Here are it's yoke readings:

3 Horizontal
8.2 Vertical

What do the monitor gurus think? Are these yoke readings close enough to try?

I am not a guru but I know that that a go... what i understand if its with in 2 or so its good but if its 10 or more its a no go. GOD BLESS
 
OK dudes, I'm ready for another tube swap on one of my many grubby monitors.

I've got a WG K7901 that I got from my recent 'Carnival Raid', it has bad 'cherry master' burn in it. Here are it's yoke readings:

2.2 Horizontal
6.4 Vertical

I have a Zenith TV with a compatible neck pin arrangement (9 pins in a hemisphere, and one 'key' pin). Here are it's yoke readings:

3 Horizontal
8.2 Vertical

What do the monitor gurus think? Are these yoke readings close enough to try?

You pansies need to learn how to swap a yoke....that way you'll (hopefully) never cross a yoke wire again.:D

Edward
 
You pansies need to learn how to swap a yoke....that way you'll (hopefully) never cross a yoke wire again.:D

Edward

Wow you assume we dont??? For me its about doing as little as possible to get my game or other people games up and running with minumum expense and time.. Yoke swaping and ring swapping isnt that hard... BUT if you have a tube with all the right stuff GO for it...Shee People that think they know what other people know... When they have no idea LOL
 
You pansies need to learn how to swap a yoke....that way you'll (hopefully) never cross a yoke wire again.:D

Edward

Ha ha, so true Edward! Guilty as charged! Let me know when you have the next 'Arcade Repair Class' down there, and I'll be right there, and learn from the pro! :-D
 
Wow you assume we dont??? For me its about doing as little as possible to get my game or other people games up and running with minumum expense and time.. Yoke swaping and ring swapping isnt that hard... BUT if you have a tube with all the right stuff GO for it...Shee People that think they know what other people know... When they have no idea LOL

Hey, it's just an inside joke -- he's talking about the first tube I tried to swap -- I got the wires crossed and blew my chassis. Edward is entitled to poke a little fun, since he's going to be repairing my mistake! :)

OK, so I'm going to give this a shot -- I'll report back with a progress report.
 
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Wow you assume we dont??? For me its about doing as little as possible to get my game or other people games up and running with minumum expense and time.. Yoke swaping and ring swapping isnt that hard... BUT if you have a tube with all the right stuff GO for it...Shee People that think they know what other people know... When they have no idea LOL

Yeah, I was just playing with Chris:)

Edward
 
OK, the tube swap is done!

This turned out really nice. The tube I used ended up being the same make as the original, though the actual tube number and ohm readings were just a little off.

Check out the pictures... I left the yoke and rings on, so I didn't have to adjest any convergence! There are only 2 issues... I have a little patch right of center that looks a little washed out, I think that's probably a gauss issue. The other is that the horizontal width is way off, I have almost 1 1/2 inches on either side of the screen. Now I just need to get an adjustment tool and see if I can fix this, or if not I read on the Bob Roberts page that the resistors can be changed to change the width -- so we'll see how the adjustment goes first.

I wonder if the width is a little off because of the discrepancy in the ohm readings?

Here are some photos.

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I took this one with a flash, the screen looks a bit washed out, but you can see how much horizontal was lost at the edges.

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OK, the tube swap is done!

This turned out really nice. The tube I used ended up being the same make as the original, though the actual tube number and ohm readings were just a little off.

Check out the pictures... I left the yoke and rings on, so I didn't have to adjest any convergence! There are only 2 issues... I have a little patch right of center that looks a little washed out, I think that's probably a gauss issue. The other is that the horizontal width is way off, I have almost 1 1/2 inches on either side of the screen. Now I just need to get an adjustment tool and see if I can fix this, or if not I read on the Bob Roberts page that the resistors can be changed to change the width -- so we'll see how the adjustment goes first.

I wonder if the width is a little off because of the discrepancy in the ohm readings?

Looks good. I'm not seeing the magnetism issue in the picture.

Regarding your width issue....if you've got 1.5 inches on each side, it'll be unlikely that that will adjust out. That's a large amount on the horizontal axis. Yep, check out Bob's page....but it's a cap you'll have to change it's value, not a resistor. One note: don't worry about this until you have the cabinet/game you're using this monitor on. If you mess with it now, you might have to do it again with a different motherboard. Some motherboards CAN display a drastically different sized image on a monitor. Don't (potentially) fix what isn't broken!;)
(and yes, your yoke {could} affect this, too)

Edward
 
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