U5000 - I need a tube.

SilverDuck

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I have a 25" wells U5000 that I need a tube for. I have a Maganavox 25" tv. What are the chances that I could use this tube with this chassis? What do I need to look for?

Thanks
 
u5000

i have a tube it was out of a police trainner i sold the boards.im not sure of the size and i dont know how you would get it.well let me know and i will find out the size if your are interested.bob
 
I have a 25" wells U5000 that I need a tube for. I have a Maganavox 25" tv. What are the chances that I could use this tube with this chassis? What do I need to look for?

Thanks

Open the TV and look for the sticker with the tube number on it....like A63xxxxx....we can look it up and go from there.
 
Should work fine, BUT you will need to use the matching yoke for the med res chassis.
 
How do I get the yoke off? It seems to be glued to the glass where the purity rings are.
 
The U5000 yoke should come right off. I have one here on my bench. Just break the glue around the rings, undo the screw, then twist to get the rings off. Mark them with a sharpie first so you can put them back one properly. Then loosen the screw for the yoke, grab with both hands and twist to break it loose, then slide it off also. Pay attention to how it's aligned with the anode cup, and how far off the tube it sits with the wedges, so you can mount it the same way on the new tube.

BTW - are you missing a tube or did you break one? If the tube is just dim, you can rejuv it. If it's burned in, then a replacement is your only option...
 
the one needle pin broke off inside the tube.

I can losen the yoke, but the purity rings are glued on. I worked and worked, and it seems they are going to crack and break before coming off the tube.

Can I destroy the purity rings, remove the yoke...and use the arcade yoke and chassis, and tv purity rings?
 
Can I destroy the purity rings, remove the yoke...and use the arcade yoke and chassis, and tv purity rings?

Yes. You want to use the TV purity rings anyway - they are adjusted for the tube, not for the chassis. If at all possible, any time you do a tube swap, you want to keep the rings with the tube they came from, and keep them aligned properly. Mark the TV rings and their position on the tube so you can put them right back.

-Ian
 
Ok...so I have a known good chassis and yoke, and 2 working 25" tv's.

What do I want to know about the tv tubes to be sure my chassis and yoke will work?
 
I have an OLD floor model RCA tv....and a more current (8 years old?) Maganavox 25" tv. Which is more likely to be "tube swap material"?
 
I have an OLD floor model RCA tv....and a more current (8 years old?) Maganavox 25" tv. Which is more likely to be "tube swap material"?

id check the neck pinout and neck size of the newer one first.

If its the sasme theres your swap.

if nto check the older tv.

ALso ohm the yoke before you swap you might get even luckier and find its close enough to plug right in.
 
I seriously, seriously doubt he's going to find a TV yoke that's going to work with this chassis. Remember, this is a medium resolution monitor... He's going to have to change the yokes.

Things you need to look for in choosing a replacement tube:

- Physical size. Make sure the tube is actually a real 25" tube, the tube number should start with a 63, which denotes the size in some wacky foreign measurement - centipedes or something. :)

- Neck connector/pinout. The neck connector needs to be the same as the arcade tube. Easy way to verify this by looking it up in the B&K tube tester manual and checking to see if it uses the same tester adapter as the arcade tube. Most arcade tubes use CR23 or CR31. Neck diameter goes hand in hand with the connector - CR23 tubes are "wide neck", and CR31 is "narrow neck".

- Mounting. Some television sets have different positions for the mounting ears, which will require fabrication of spacers to mount the tube into the arcade frame. (i.e. the tube ears are too far forward) Just be sure when fabricating spacers, that if you use wood, you still need to ensure the dag ground strap makes good electrical connection to the metal frame. This is usually accomplished by the strap looping around two opposite tube ears, which then get bolted to the frame. The metal bolts should make a sufficient ground, just ensure that your spacers don't interfere with that, and double check. Sometimes the bolts screw into "keep nuts" clipped into the frame, which may or may not make a good electrical connection.


Edit: I would start by checking the newer TV first. An old enough set will have a delta gun picture tube, which won't be usable. Besides, wouldn't you rather keep the older set around and working so you can play your Atari 2600 on it? :D

Also, another thing to check - deflection angle. Some TV tubes are shallower than the arcade tubes. Arcade tubes for 25" monitors are 100 degree deflection, 19" tubes are 90 degree, with the obvious exceptions on vector monitors. Most modern 25" sets are 100 degree as well, but I've seen some 110 degree ones. It'll be obvious by comparing the two tubes - they look a lot different. Electrically they'll still work, but you might not be able to get it to converge.

-Ian
 
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So, I could just crack open the case, get the number off the tube without even removing the tube from the tv case? Post the tube number here, and we can look it up?
 
Yes. Or just look at the tube and look it up yourself. Compare the physical appearance of the neck connector. If it's different, then you don't even need to look any further. If it looks right, and the tube looks similar, then check the number. You will be surprised just how many tubes are all compatible...

But yeah, take the cover off, look at it, and post the number. Sometimes you don't even need to open the set, you can usually look in through the vents in the back with a flashlight.

-Ian
 
A63AAX ZERO ONE x Is this a good tube number?

Yes. It's a 25" tube, with a standard CR23 neck. IIRC, the U5000 uses a CR23 tube - but it's been a while since I worked on one, and I have tried my absolute best to block all memory of that horrible monitor out of my mind. The nightmares... So many blown vertical IC's. Oh, the carnage! The HOTs that had to suffer! Shudder....

-Ian
 
So....get the yoke off my U5000, use the U5000 yoke, the TV purity rings, and then I'm in business?
 
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