Amplifone Tube Swap ...

[Level42]

Agreed 100% with everything Komodo writes.

Here's the simple frame I built for a 25" tube:

Crude and simple but effective and amazingly firm.

 

[VectorJunkie]

Agreed 100% with everything Komodo writes.

Here's the simple frame I built for a 25" tube:

Crude and simple but effective and amazingly firm.

You using a WG6100 yoke on that thing? How well does that work? Ok I see a WG serial number on that thing.... I thought the 25" monitors were Amps only. Did WG make one?

 

[m_mcgovern]

You using a WG6100 yoke on that thing? How well does that work? Ok I see a WG serial number on that thing.... I thought the 25" monitors were Amps only. Did WG make one?

6100 monitor, 25" amplifone monitor use same wg6100 yoke (wire color differences)
19" amplifone monitor uses a different yoke (amplifone)

 

[VectorJunkie]

6100 monitor, 25" amplifone monitor use same wg6100 yoke (wire color differences)
19" amplifone monitor uses a different yoke (amplifone)

Thanks for the info... Didn't know they mixed up the parts like that for the 25" solution.

 

[Level42]

Note that I never got it properly converged. It's not mine though, I have a full original (yes ALL boards are the original serial nr.) Amplifone 25" in my SW cockpit.

That one was from a friend.

I have a feeling that it's not possible to get a 6100 tube right with a 25" CRT. I think the angle is different (Can't remember, there are so many combo's "possible").

As far as I know the WG6100 was a 19" only monitor. So, I assume this is a hack.

So the full info would be:

6100 monitor (19") and 25" amplifone monitor use same wg6100 yoke (wire color differences)
19" amplifone monitor uses a different yoke (amplifone)


[Edit] Mmmm, I never messed with those magnets (or are they simply metal strips) under the tape inside the yoke (didn't even know they were there). Maybe the reason for not getting it converged correctly lies in this ?

 

[joeycuda]

6100 monitor, 25" amplifone monitor use same wg6100 yoke (wire color differences)
19" amplifone monitor uses a different yoke (amplifone)

What are the 'wire color differences' you speak of? Will the WG6100 yoke plug right into the Amp boards? I just got a WG yoke and will be going this route.

 

[Level42]

Well, since WG6100 19" yoke = Amplifone 25" yoke, it should indeed.

Even the 19" Amplifone yoke should fit straight away since it runs on exactly the same Amplifone boards.

 

[dezbaz]

Great thread guys, very useful - cheers

Anyone mind if I use the links in my Amplifone site below?

Dez

 

[m_mcgovern]

What are the 'wire color differences' you speak of? Will the WG6100 yoke plug right into the Amp boards? I just got a WG yoke and will be going this route.

Yes. Connector between "amplifone" 25" yoke and 6100 yoke are identical. Wire positions are identical...so you can plug it in with no worries that it will work properly. However, wire colors between the two are different. I'll see if I can add a pic later tonight.

 

[joeycuda]

Yes. Connector between "amplifone" 25" yoke and 6100 yoke are identical. Wire positions are identical...so you can plug it in with no worries that it will work properly. However, wire colors between the two are different. I'll see if I can add a pic later tonight.

Good info, thanks! I didn't know..

 

[kentmurphy]

I'm back and I have problems. I degaussed the tube several times and then attempted to adjust the purity per the manual. I cannot get the colors consistent across the screen. The upper right, lower right, and upper left corners are off. The videos below though crappy should help you understand the problem I am facing.

http://www.youtube.com/watch?v=UyVHaZCQmRc
http://www.youtube.com/watch?v=TcDv-nquGiE
http://www.youtube.com/watch?v=9tGgQPKRXCQ

Any ideas? Could it be the magnets taped to the yoke or is the tube bad?

Kent

 

[kentmurphy]

I hope this isn't my problem ...

http://forums.arcade-museum.com/showthread.php?t=172652

Kent

 

[kentmurphy]

A few more comments. The tube is facing north. I tried a little experiment. I rotated the yoke a full 180 degrees to see if the discoloration followed or not. It did not follow leading me to believe this is an issue with the tube and not the yoke or the magnets in the yoke. Does this make sense?

Kent

 

[Mark H]

Set the screen for a solid green cross hatch.
let it run for 10 minutes or so.
Degauss the tube.
Make sure the convergence rings are 180 degrees opposite each other (no correction) you can even leave them off at this point.
Loosen up up the yoke and slide it back and forth untill you get a solid green.

*The solid green is the key, untill you get that, you are just wasting your time with the rest of the colors.*

when adjusting the other colors, yo may have to move the purity rings bcak and forth a bit get them dialed in 100%

mh

 

[kentmurphy]

Mark,

Ok so here's what I did. Removed the rings, let the tube warm up for 10 minutes, degaussed it, set the self-test to the green crosshatch, and then moved the yoke backwards and forwards. Regardless of what direction I move the yoke I cannot seem to get the color green to cover the entire screen.

When I move the yoke backwards, the color red starts to move toward the center and the edges start to change to blue. As I move the yoke forward, the color red starts to move toward the edges, but I cannot move the yoke far enough forward to make red completely disappear. The upper left and lower right corners are still red. Does this make sense?

I'm not exactly what to do next. Any ideas? Would pictures help?

Kent

 

[kentmurphy]

Well, I punted, at least for now. I put the old tube back in, set the purity, converged it, and it looks better than it did before. It has the small burn hole in the center, but I guess I'll have to live with. I really don't know what is wrong with the new tube, but I couldn't get the purity right. If anybody has any suggestions I would love to hear them. I intend to try again in the next day or two, but I need a break.

Thanks,
Kent

 

[KenLayton]

I am swapping my old Amp tube with a NOS one. I've removed the rings, the yoke, and I have pulled the tube from the cabinet. I have a few questions though.

There is tape around the neck of the old tube. See the first pic. Do I need to put a similar type of tape on the new tube?

There is tape inside the yoke. See pics 2 and 3. Should I leave it there or remove it?

The yoke windings are dirty. Would it hurt to wipe down the windings with a dry rag?

http://cid-4127ea3a33b50049.office....Arcade/machines/starwars/images/tubeswap1.jpg
http://cid-4127ea3a33b50049.office....Arcade/machines/starwars/images/tubeswap2.jpg
http://cid-4127ea3a33b50049.office....Arcade/machines/starwars/images/tubeswap3.jpg
http://cid-4127ea3a33b50049.office....Arcade/machines/starwars/images/tubeswap4.jpg

Thanks,
Kent

1. That tape is called " 3M glass cloth tape". It is there to provide a non-slip surface for the yoke to clamp to. It has a special adhesive that sticks to glass and the heat of the tube's filaments (heater) bonds the glue. The tape comes in a roll like electrical tape, but this stuff is EXPENSIVE! Costs about $20 a roll from most industrial suppliers. Here in Olympia, Washington I buy it from regional electrical contractor supplier, Platt Electric.

2. Those long strips are not tape, but rather long strips of thin plastic with a tiny magnet in the end. These need to be transfered to the new tube exactly like they are on the old tube.

3. The tape inside the yoke stays with the yoke. Leave it alone.

4. To clean the yoke wires, use a 1" bristled paint brush to knock the dirt loose and a can of air to blow it out.

 

[kentmurphy]

1. That tape is called " 3M glass cloth tape". It is there to provide a non-slip surface for the yoke to clamp to. It has a special adhesive that sticks to glass and the heat of the tube's filaments (heater) bonds the glue. The tape comes in a roll like electrical tape, but this stuff is EXPENSIVE! Costs about $20 a roll from most industrial suppliers. Here in Olympia, Washington I buy it from regional electrical contractor supplier, Platt Electric.

Since I wasn't sure what type of tape it was, I used athletic tape. Seems to do the job fairly well.
http://www.walgreens.com/store/c/wa...-purpose-athletic-tape/ID=prod2301329-product

2. Those long strips are not tape, but rather long strips of thin plastic with a tiny magnet in the end. These need to be transfered to the new tube exactly like they are on the old tube.

Interesting. I have several new magnetic strips which I intended to put on the new tube while adjusting the dynamic convergence. According to the Amplifone manual, the dynamic convergence adjustment is the last step in the process so these magnets were not on the tube while I was setting purity. Do you think this might be the reason I can't get good overall purity?

3. The tape inside the yoke stays with the yoke. Leave it alone.

4. To clean the yoke wires, use a 1" bristled paint brush to knock the dirt loose and a can of air to blow it out.

Thanks Ken!

 

[Level42]

2. Those long strips are not tape, but rather long strips of thin plastic with a tiny magnet in the end. These need to be transfered to the new tube exactly like they are on the old tube.

I am quite surprised to read this from you Ken. AFAIK the strips do not carry a magnet but simply a piece of metal to influence the magnetic field created by the yoke to correct the edge convergence.

Also, transferring these exactly to the new tube sounds strange to me ? I thought these are used to "iron out" tiny production tolerances of the tube. But, as you put it, they are actually "ironing out" the tolerances of the yoke ?

 

[VectorJunkie]

I am quite surprised to read this from you Ken. AFAIK the strips do not carry a magnet but simply a piece of metal to influence the magnetic field created by the yoke to correct the edge convergence.

Also, transferring these exactly to the new tube sounds strange to me ? I thought these are used to "iron out" tiny production tolerances of the tube. But, as you put it, they are actually "ironing out" the tolerances of the yoke ?

Like Ken would be wrong...

http://www.wellsgardner.com/service/monitor_terminology.asp

Read "Yoke Tabs".... It says there is a magnet.