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stefuel
Joined: 07 Mar 2006 Posts: 3353 Location: Green Harbor MA USA
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| Posted: Sun Jan 31, 2010 1:11 pm Post subject: AmPro HD convergence tray question |
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I'm having a problem on the left side converging my HD projector. I have a horizontal s-curve in all three colors to the left of center. On the convergence tray (which is comprised of 4 boards) I found a blown cap on the PLL board. Prior to changing that, the turning of "R-4" (registration phase adjustment pot) resulted in moving the blanked sides left and right. After replacing the cap with the exact part, the blanked edges stay in place and now the test pattern moves left and right but the curve does not change. I think there must be something else wrong somwhere in the tray assembly but I cant find it. I have many complete tray assemblies but they are a little different than the HD version. On the HD version, on the center board there is IC-11, IC-12 and C68 through C72. On the HD these are populated and the rest that I have are not. These are not even listed in my manual. I have no idea what IC-11 and IC-12 even do. I'd like to just pop in one of my spare trays but I'm not sure if I should even try it knowing there is something different.
This is the last thing I need to resolve so that I can go ahead and calibrate the projector with it's new set of Thomas tubes.
Note: the tubes are not the cause of the curve. It was there prior to re-tubing. Thanks,
Chip
_________________ Chip
A Barco is only a AmPro with training wheels
Card carrying member of the AVS chain gang.
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tse
Joined: 03 May 2006 Posts: 1014 Location: Sweatbucket, Fl.
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| Posted: Sun Jan 31, 2010 5:49 pm Post subject: |
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The only schematic I have of the OSD/Waveform bd is labeled "W/O INT". It doesn't show IC11 & 12. The missing parts are a programmable part that contains a waveform and a digital to analog converter that takes the digital information and makes an analog signal. It looks like the signal would be "DH BOW" if the parts were there.
The spare bds should work, if they are good, but some waveform will not be there.
If you are going to try unknown condition bds in your 4600 with brand new tubes it would be a good idea to unplug the power going to the Spellman so the tubes can't come on. Then, if a fuse blows or something else dangerous happens, your tubes won't be at risk. P44A is the power connector. It is a three position connector with two wires installed. It comes out of the Spellman and plugs into the mother bd. Unplug the connector, try the registration bd watching for blown fuse (LED on SMPS not on), try 30 code which will give HV, G1, and G2 error.
If no smoke signals, blown fuses, or other strange behaviour happens it might be safe to plug in the Spellman and see how the registration bd works.
Remember to unplug the projector line cord befor plugging/unplugging P44A.
Scott
_________________ "Were we directed from Washington when to sow and when to reap, we would soon want bread."
Thomas Jefferson
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Curt Palme CRT Tech
Joined: 08 Mar 2006 Posts: 24396 Location: Langley, BC
TV/Projector: All of them!
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| Posted: Sun Jan 31, 2010 6:02 pm Post subject: |
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Scott is right, swapping boards between 4600s seems to be easy and you don't have the compatibility issues that we did with the older 2000s. Heed the 'unplug the HVPS' advice!
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stefuel
Joined: 07 Mar 2006 Posts: 3353 Location: Green Harbor MA USA
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| Posted: Sun Jan 31, 2010 7:10 pm Post subject: |
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This is me with a 45 jammed up against my temple. With the new convergence tray I have test patterns that are about 99% perfect. What little curves at the very edges is evenly disributed between the right and left sides. Now I have banding
Life would be so much simpler if 1080P in it's native form fit within AmPro's available raster. That would allow me to increase the size enough to loose the little curves at the edge and all would be well with the world. But nooooo.
_________________ Chip
A Barco is only a AmPro with training wheels
Card carrying member of the AVS chain gang.
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stefuel
Joined: 07 Mar 2006 Posts: 3353 Location: Green Harbor MA USA
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| Posted: Sun Jan 31, 2010 11:36 pm Post subject: |
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I left the spare tray assembly in for a while and let the kids watch a movie. That gave me time to examine the complete assembly under a lighted magnifying glass. I had already replaced "C-28" on the PLL board and that seemed to make some difference. However, after looking more closely at the whole assembly, I discovered that R10 on the power supply board was toast. That is a 2.2 ohm resistor and I replaced it with the exact one. I'm going to swap out the tray again and see what happens. There were no other visually damaged parts and I looked at the whole assembly. I probably should inspect every board in this projector one by one. That should kill a week.
BTW, what is "DH BOW"???
_________________ Chip
A Barco is only a AmPro with training wheels
Card carrying member of the AVS chain gang.
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tse
Joined: 03 May 2006 Posts: 1014 Location: Sweatbucket, Fl.
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| Posted: Mon Feb 01, 2010 1:01 am Post subject: |
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That makes sense. C28 is across the +5VA rail and R10 is in series with the regulator for the +5VA rail. You might have just fixed it. Those tant caps are not the most reliable type of cap there is. It probably just up and died, no reason to it.
I think DH BOW is delayed horizontal bow. I have no idea what it is used for.
Scott
_________________ "Were we directed from Washington when to sow and when to reap, we would soon want bread."
Thomas Jefferson
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