Panasonic AG-DV2500P, Service Manual

Page: 272 / 306

3-1
3.1 PRECAUTIONS FOR ELECTRICAL ADJUSTMENTS
Electrical adjustments should be performed only when they are
required, for example, during maintenance. Electrical adjust-
ments that are possible only after mechanism adjustments
should be performed after completing these. Before proceed-
ing to perform electrical adjustments, be sure to warm up the
unit for at least 10 minutes after turning it on.
Use the 10:1 probe with the oscilloscope unless otherwise speci-
fied.
3.1.1 Measuring instruments and Tools required for
adjustments
(1) Measuring instruments
• Oscilloscope: 2-trace, 100 MHz or more.
• NTSC/PAL waveform monitor (WFM)
• NTSC/PAL Composite and Y/C video signal generator
• Frequency counter: 10 MHz or more, resolution 100 mV
or less.
• Monitor TV
(2) Tools
SECTION 3
ELECTRICAL ADJUSTMENTS
3.1.2 Alignment tape specifications
VFK1842
Table 3-1-2
1
2
Moving
image
Color bars
Moving image
audio
1 kHz
Block noise check 10
10 •Interchangeability
adjustment
•Video/audio play
circuit
check/adjustment
Audio
signal
Video
signal
Time
(min.)
Applications
No.
3.1.3 Signals required for adjustments
NTSC and PAL color bar signals are required on “3.3 VIDEO
SYSTEM ADJUTMENT”.
NTSC:
100% color bars (100, 0, 100, 0) (Without SETUP)
100% color bars (100, 7.5, 100, 7.5) (With SETUP)
PAL:
100% color bars (100, 0, 100, 0) (PAL does not use SETUP.)
(1) Composite 100% color bars
(2) Y/C 100% color bars
Fig. 3.1.3 (1)
Fig. 3.1.3 (2)
1
2
Alignment tape
VFK1842
VFK1846
Rewrite board (Jig connector)
NTSC : A = 0.714, B = 0.286,
C = 0.0536S (SETUP 7.5%)
PAL : A = 0.7, B = 0.3, C = 0
A
Vp-p
C
Vp-p
B
Vp-p
1.24
Vp-p
Y/C (C)
NTSC : A = 0.286, B = 0.84 [SETUP 7.5%]
(0.9 [SETUP 0%])
PAL : A = 0.3, B = 0.885
A
Vp-p
B
Vp-p
A
Vp-p
1.0
Vp-p C
Vp-p
B
Vp-p
Y/C (Y)
NTSC : A = 0.714, B = 0.286,
C = 0.0536 (SETUP 7.5%)
PAL : A = 0.7, B = 0.3, C = 0
Table 3-1-1