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Discussion Starter · #1 ·
Can any of you Ampro 4300 owners give me an idea of where your sub brite and sub contrast settings are set to.
 

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Rick,


Bright = 40

R,G, and B sub-bright are in the 70-80 range


Contrast = 55

R,G, and B sub-contrast are in the 60-70 range


This is on a 45"x80" screen.


I set the values using Video Essentials through my HTPC. I still need to tweek things a little depending on what I am watching.
 

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Discussion Starter · #3 ·
how do you set the g2? (the little red pots on each CRT) I need to get those right before I set up the rest, don't I?
 

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Rick,

Yes, the G2 needs to be set correctly first. To set G2 you need to cut off the tube using the remote and then adjust the G2 pot so that the raster disappears completely (counter-clockwise) and then turn the G2 back up slightly until the raster just appears.


KennyG wrote a thread on using a colorimeter to assist in the calibration of the G2, brightness, and contrast.
 

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I used AVIA to set G2 by bringing up the black bar pattern and lowering bias until the second bar was just above black. I did this for each individual color. Is that an acceptable method?
 

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John,


Not good.


You have to first set G2 while each crt is "cutoff", not while displaying any sort of video image. The intent is to make sure that the video raster (which is normally not visable) is blacked out during the video beam retrace period.


To illuminate the crt phosphors, beam current must flow through the crt cathode element at the back of the tube to the anode faceplate. This current is generated by the neck board amplifier. If the raster is not totally blacked out during retrace, then beam current can be drawn during the period of time when it is normally shut off. This has the downside effect of generating extra heat in the amplifier card, and long term wear and tear on the phosphor.


Walter Allen (from Elite Video) discussed the process in more detail when he was a recent guest:

http://www.avsforum.com/avs-vb/showt...hreadid=248180


Ray
 

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Discussion Starter · #7 ·
Ray your link is wrong, could you please post the correct link. ( I searched and couldn't find it and need to do this right) Thanks in advance!
 
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