Video Amplifier Alignment Procedure - EDL Displays 6120 Operation And Maintenance Manual

VIDEO AMPLIFIER ALIGNMENT PROCEDURE

The Model 6115, 6116 and 6119 Video Amplifiers provide start-of-the-art in design and
performance. They provide for control of:
1. Contrast (Gain)
2. Brightness (Black level)
3. Color tracking
4. Automatic Gain Control
MINIMAL ALIGNMENT PROCEDURE
There may be the need to "touch-up" the Video Amplifiers to the video system. Only the Black
level and Gain controls should be adjusted in this manner.
1. The BLACK level control should be adjusted first for color balance on the black or
known dark gray portion of an image.
2. Then the GAIN adjusted for color balance on a high brightness white portion of the
image.
3. Always adjust BLACK level before GAIN.
Video Amplifier alignment should not be necessary unless replacement of the following
occurs.
1. Cathode Ray Tube (CRT)
2. High Voltage Power Supply
3. Video Amplifier Module
Should the CRT be replaced, a complete procedure is necessary and will be presented later.
Replacement of either the High Voltage Power Supply or one or more Video Amplifier Module
requires only a partial procedure which will be presented here first.
EQUIPMENT REQUIRED:
1. Astro Designs VG 809 test pattern generator or equivalent.
2. Minolta TV2130 Colorimeter or equivalent.
3. BNC cables as required.
4. Insulated 1/4" straight screwdriver or adjustment tool.
PARTIAL PROCEDURE
Replacement of a Video Amplifier Module may only require the adjustment of the replaced
modules Black level and Gain pots.
The Black level may be adjusted on the replaced module by:
1. Set the Video generator for 20% amplitude flat white field.
2. Set front panel Brightness and Contrast controls fully CW.
6115 - 6120 Operation and Maintenance Manual ©EDL Displays, Inc. January 1997
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