Sony HCD-GZR888D Service Manual page 28

HCD-GZR888D/GZR999D
VIDEO SECTION
Video Level Check (VIDEO BOARD)
Purpose
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.
set
J1502
VIDEO OUT
Procedure:
1. Connect oscilloscope to VIDEO OUT jack.
2. Load a DVD reference disc playback.
3. Check the video signal level is 1.00±0.07Vp-p.
(WHITE 100%)
28
oscilloscope
75 Ω
+
–
1.00 ± 0.07 Vp-p
DECK SECTION
0 dB = 0.775V
Except E2, E51, AR, MX Model:
1. Demagnetize the record/playback head with a head demagne-
tizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in this
service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit ad-
justment.)
6. The adjustments should be performed for both L-CH and
R-CH.
7. Switches and controls should be set as follows unless other-
wise specified.
• Test Tape
Tape Signal
P-4-A063 6.3 kHz, –10 dB
Record/Playback Head Azimuth Adjustment
Procedure:
1. Mode: Playback
test tape MAIN board
P-4-A063 IC101
pin wh (L-CH)
(6.3 kHz, –10 dB)
pin ql (R-CH)
MAIN board
IC101
pin t; (GND)
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
within
L-CH
1 dB
peak
output
level
R-CH
peak
screw
position
L-CH
peak
Used for
Azimuth Adjustment
level meter
+
–
within
1 dB
screw
position
R-CH
peak