Sony DNW-A100 Maintenance Manual page 476

7-1-3. Video Tracking Check and Adjustment
6. Check the Y/C Head Head-to-tape
Contact
(1) Connect the oscilloscope.
CH-1: TP500/EQ-56 board (A2A6 signal)
CH-2: TP1500/EQ-56 board (B2B6 signal)
TRIG: TP100/EQ-56 board (A1A5 SEL signal)
Oscilloscope setting :
CH-1 : 200 mV/DIV
CH-2 : 200 mV/DIV
TIME : 5 to 2 ms/DIV
n
The Ya and Yb signals of Betacam/Betacam
SP are output from TP500 under playing back
the CR2-1B/PS. In the same way, the Ca and
Cb signals are output from TP1500.
(2) Press the EJECT button so that the unit put
into the unthreading end state and remove the
SR2-1/P.
At the same time, the tracking VR becomes
to be not effective.
(3) Set the CR2-1B/PS and put a weight on the
cassette so that it does not rise up.
Weight about 1000 g is suitable.
(4) Press the PLAY button to play back the CR2-
1B/PS. (Any portion playback is acceptable)
The waveform is displayed on the oscillo-
scope as shown in the figure.
(5) Check that the RF waveform of Ya, Yb and
the RF waveform of Ca, Cb satisfy the
specification 2.
7. Mode Setting (REC Head PB)
(1) Press S1101 switch on the SS-63 board to
enter the maintenance mode.
(2) Set the cursor "*" to the "M0 : TAPE
MAINTENANCE" and press the SET button.
(3) Set the cursor to the "C4 : OTHERS" and
press the SET button.
(4) Set the cursor to the "C48 : PATH MODE
SEL" and press the SET button.
(5) Check that the "Switching PB" is indicated,
and press the SET button.
Then, mark is indicated at the right up
corner on the monitor.
n
Refer to Section 4 of Maintenance Manual
Part 1 "Maintenance Mode" for more infor-
mation about the maintenance mode.
7-16
. Connection of the ocsilloscope
CH-1: TP500/EQ-56 board
CH-2: TP1500/EQ-56 board (B2B6 signal)
TRIG: TP100/EQ-56 board
<EQ-56 board, side A>
A B C
TP100
. Alignment tape : CR2-1B/CR2-1B PS (Any portion)
(Tracking VR : Not effective)
RF waveform
CH-1
of Ya
(Ya,Yb)
CH-2 RF waveform
(Ca,Cb) of Ca
TRIG
(A1A5 SEL signal)
B A
Spec. 2
B
x 100 > 85% (Drum entrance side)
A
C
x 100 > 85% (Drum exit side)
A
D
x 100 > 85% (D is minimum output level of waveform)
A
Y/C Head Head-to-tape Contact Check
(A2A6 signal)
(A1A5 SEL signal)
D E F G
TP500 TP1500
RF waveform
of Yb
RF waveform
of Cb
a b
D C
DNW-A100/A50/A45
DNW-A100P/A50P/A45P
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2
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