Barco GRAPHICS 1209S, Руководство по обслуживанию

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Date: 10/02/97 R762745
QUAD Comb_Filter R762745
14
ADJUSTMENT PROCEDURE QUAD DECODER R762745
Adjustment procedure
Location of controls
C11 C13 P10
C16 C18
FI10 FI12 FI11
Factory pre-adjusted
Re-adjustment NOT allowed
L100
L272
L12
Factory pre-adjusted
Re-adjustment REQUIRES
special equipment
Measurement point 4Fsc
A. Adjustment Comb Filter 1. Quick adjustment for Color display
- Connect to the VIDEO input e.g. an electronic PAL color test video signal.
- Switch the projector in the VIDEO MODE. Select source 1.
- if there is no colour, adjust trimming capacitor C11 for color display.
- Connect to the VIDEO input e.g. an electronic NTSC3.58 test video signal.
- if there is no colour, adjust trimming capacitor C13 for color display.
Final adjustment of the trimming capacitors C11 and C13 is explained in the
'adjustment of the decoder' (see further).
2. Oscillator adjustments
- No input signal connected to the VID/LUMA and CHROMA inputs.
- Connect pin 28 of IC11 to L13 (forcing decoder into PAL mode).
- Connect a Frequency meter (Range 20MHz-accuracy of 10Hz) to the 4Fsc line
(pin 17 IC15).
- Adjust the trimming capacitor C18 for a frequency read out of 17.734476 MHz
with an accuracy of 80Hz.
- Connect pin 26 of IC11 to L13 (forcing decoder into NTSC mode).
- Connect a Frequency meter (Range 20MHz-accuracy of 10Hz) to the 4Fsc line
(pin 17 IC15).
- Adjust the trimming capacitor C16 for a frequency read out of 14.318180 MHz
with an accuracy of 80Hz.
Measurement
point 4Fsc