Kristel 1428-30k series, Руководство по обслуживанию

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CRT diagnostic software included in Kristel 3.5” diskette
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hipot tester
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video generator
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TEST Bezel - fixture model / depending on customer availability
PROCEDURE
⇒
Apply AC recommended power and video signal from customer supplied generator
or use IBM compatible computer
⇒
Adjust screen control (FBT) to be able to view screen & focus control to best possible
setting.
⇒
Convergence: some fine adjustment with pre-mated yokes to CRT can be achieved with
magnetic tabs (see instructions and theoretical considerations - how to provide a best
convergence.
⇒
Adjust B+ from VR501 / per CRT requirement:
•
connect the positive lead of multimeter to D508, negative to chassis
•
adjust VR 501 to obtain the voltage resulted from the spec. of the CRT
⇒
Select crosshatch pattern from video source / 31.5KHz (640x480)
⇒
Vertical linearity adjustment: adjust VR310 to allow no more than 3.0mm max.
misadjustment.
⇒
Vertical size is performed from VR309 remote control potentiometer
⇒
Width size adj. is performed from VR307 and VR501. maximum attention for
heater voltage / maximum permissible value must be between 5.9 - 6.5vDC /
⇒
Horizontal raster centering is performed from VR604
⇒
Horizontal Phase adjustment:
•
input 31.5kHz timing with crosshatch pattern
•
adjust VR604 to center the picture per specs.
⇒
Pincushion adjustment: VR304 and VR301
•
input 31.5 kHz (640x480) timing with crosshatch pattern
•
adjust VR304 and 301 to obtain the best pincushion pattern
⇒
Focus adjustment:
•
display any character all over the screen, set contrast in max. and brightness in cut off po-
sition. Adjust focus for best resolution possible.
⇒
Horizontal Oscillating Frequency, connect a capacitor 10
μ
F/50volt, to Hsync from video
PCB to GND, than adjust VR601 till the sync slash blanking bar is vertically stable possible
after that remove the jumper
pg.19
1428-30k series