Barco CVM 2037, Инструкция по эксплуатации

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Component input and audio circuit alignment (cont.)
,
For authorized personnel only
2 Decoder Section and Lum & Sync Section
Factory adjusted, adjustments to be carried out only in
case of replacement of compenents in the decoder
section and/or Lum & Sync section.
2.1 Sandcastle pulse
Program the OPT input for S-VHS format.
Apply a PAL S-VHS colour bar test signal to the inputs : chrominance (C) to
CHANNEL A,
lumi-
nance (Y) to
CHANNEL B.
Connect an oscilloscope to TP10 (sandcastle pulse).
Synchronize the oscilloscope to the video input signal.
Short circuit bridge BR5.
Adjust P3 for zero beat of the sandcastle pulse on TP10.
Open BR5.
2.2 PAL decoder section
Connect the oscilloscope to TP15 (U6 chrominance input).
Adjust P8 for 200 mVpp chrominance signal at TP15.
Connect the oscilloscope to TP14 (R-Y).
Short circuit bridge BR6.
Adjust C58 for zero beat of the R-Y signal at TP14.
Open BR6.
Connect the oscilloscope to TP13 (B-Y).
Adjust L2 for correct phase and P6 for correct group delay.
2.3 NTSC decoder section
Apply a NTSC S-VHS colour bar test signal to the inputs : chrominance (C) to
CHANNEL A lumi-
nance
(Y) to
CHANNEL B.
Connect the oscilloscope to TP14 (R-Y).
Short circuit bridge BR6.
Adjust C59 for zero beat of the R-Y signal at TP14.
Open BR6.
Adjust P7 for correct phase (monitor still in calibrated position).
2.4 Luminance
Apply a 100% White Field video signal
(CHANNEL B
is sufficient).
Install the colour analyzer, probe attached to the screen.
Adjust P2 for 120 nit on the screen.
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