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Discussion Starter · #1 ·
Well, I'm neck deep in setting up my low hour 3600, everything is looking pretty good...except my Raster centering.

In order to get the Rasters centered I have to adjust the Phase to about 90.

As I recall, I was able to move the Rasters in my NEC XG using...I think some of the CPC magnets on the tubes. However Ampro ownly uses two pair of CPC magnets, one for Astig and one pair for flare.

Is there a way to move the Rasters so I can bring the Phase adjustment back to it's centered position?
 

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Are you using the detailed setup guide ? On the 4600 I had, I think there was only electronic controls for raster centering, just like the XG NEC's. Do you have the manual for the 3600 ? I've got most of it if you want. Its missing (2?) pages.
 

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Discussion Starter · #3 ·
Thanks, I have both the owners manual and the tech/repair manual...the electronic centering you speak of is "Phase".

I'm not sure how this works, but perhaps it is not a voltage change...perhaps it is some sort of phase adjustment (gee imagine that :)) In which case a high adjustment will not be hard on the pj.

Last night I adjusted Flair and Astig...nothing else on those tubes moved the image around on the tube...so I suppose I've got to live with this....but like I say, if it is actually a phase adjustment, then it's probably no big deal.
 

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Discussion Starter · #4 ·
Perhaps someone can clue me in on something else that is a little strange???

When I use the "step-by-step" setup guide, my blue gun's vertical alignment must be max'ed out to 100% and it's still not enough!!! Red is also a ridiculously high 74%

However, when I bring up the crosshair pattern in the AVIA disc and check my settings...the blue and red are within 2 clicks of null (50%)...what gives???


I suppose it's a good thing I don't need that setup guide whatever the reason.
 

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There are two types of vertical shift on the Ampro. The first is the static vertical shift (probably the high values you are talking about) and must be performed with registration turned off. The second is the dynamic vertical shift done with registration turned on (the ones near the 50% point in your case).
 

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Discussion Starter · #6 ·
I don't know...I turn the register off (55 code) and look at static shift, and both Blue and Red readings are within +/- 5 of the center position (50) however, much of the other convergence is off.

Turn the Register back on, and the dynamic readings are close to the same, and of course the rest of the convergence come back into correct adjustment.

So, the only time I can get these very high readings to show up is in the instructional setup.
 

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Perhaps its all related to the internal patten generator. That could be flakey ? I don't think they broke the bank on it, on the one I had, I NEVER saw a clean pattern, it was always corrupted in some way, yet the end result image was always excellent.
 

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Discussion Starter · #8 ·
Yes, very strange...the internal patterns always show some areas of convergence to be off, yet I can bring up the crosshatch pattern in AVIA and everything is right on!?
 

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Kenny,

I don't think you can get to the red and blue static vertical shift with the shift button on the remote. To get into the red and blue static vertical shift, you need to use the 40 and 41 codes when registration is off.
 

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Discussion Starter · #10 ·
Thurman you are correct when I use the 40&41 codes I get the static shift readings.

My Blue is maxed out at 100%, and Red is at 74%...there has got to be a mechanical adjustment to fix this...and from the readings I'd say it's mostly the Green tube that needs it.

However I must say, this picture is starting to look as good as I'd hoped when I sold the NEC!
 

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Kenny,


On your first comment about the Phase control, remember that the adjustment is just shifting the video image on the raster, it is not moving the raster itself. The raster cannot normally be seen unless you turn the brightness up, and the contrast down. That will let you see the full raster whose video level is normally set to be "blacker than black" such that it can't be seen.


I had a problem with the blue raster position on my 4200. It was shifted too far to the left on the crt face. The normal electronic controls lacked the range to center it properly with the red and green.


The only mechanical raster adjustment I found was to rotate the magnetic focus coil on the blue crt neck. This caused some up/down and left/right movement of the raster, and let me shift it to the right somewhat. I was joking about adding some refrigerator magnets to deflect the beam, and I didn't realize at the time that the focus coil itself is a large magnet. I had to rotate it a full 180 degrees to pull the raster over. It looks kind of strange, but it gets the job done.


I also found that moving the coil assembly forward or back on the neck will change the focus. In my case this was good because I had just replaced the high voltage power supply, and I couldn't get the focus set with the electronic controls. I had to move the coils forward about 1/4 inch to get the focus to come back in.


Ray
 

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Discussion Starter · #12 ·
Thanks Ray, that was it! Rotating the focus coils took care of it...they are now both at 50 +/-2, so that solves that...once I started playing with them it suddenly hit me that I'd also done this with my first XG, I had just forgotten, and my second one didn't need it.

Sliding the F coil back about 1/4" also gave me a tighter focus on the Green, so thanks again.
 
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