Sony KV-32HS500 Training Manual page 50

All the video signals pass through the A-board unprocessed and are then applied to the B-board through CN2002
(A-board) and CN3203 (B-board). All video processing is performed on the B-board (DRC and MID processing).
The DRC circuit will double the horizontal frequency for input signals with 15.75KHz (NTSC) horizontal inputs.
The MID circuit will up-convert the horizontal frequency of the input signal to 33.75KHz, which is the scan rate of
the DA-4 and DA-4X chassis. Table 5-2 shows the signal standard and its associate horizontal frequency.
Input Signal
Standard NTSC 480i
High Resolution 480p
High Resolution 720p
High Resolution 1080i
The following is a description of the signal flow for each standard listed in Table 5-2:
•
15.734KHz input: DRC circuit up-converts to 31.5KHz and MID circuit up-converters to 33.75KHz
•
31.5KHz input: MID circuit up-converts to 33.75KHz
•
33.75KHz input: XBR, HV pass through MID; HS bypass MID circuit
•
45KHz input: MID circuit down-converts to 33.75KHz
The output of the MID circuit is then applied to the CRT drive IC2801, which will then drive the CH/CX boards in
the DA-4 (shown in Figures 5-2 and 5-3, and CR, CG, CB boards in the DA-4X chassis (boards not shown, but
the circuit operation is same as Figure 5-2).
CN2805
12V
B BOARD
D BOARD
CN5003
200V
HEATER
Table 5-2 - Input Signal Standard and Horizontal Frequency
CX BOARD
CN9001
R
1 1
G
3 3
5 5
B
7 7
IK
8 8
Q9001
CN9002
1 1
4 4
NOTE:
CIRCUIT OPERATION IS IDENTICAL FOR DA-4X.
THE IC's ARE LOCATED ON SEPARATE BOARDS
(CR, CG, CB)
FIGURE 5-2 - DA-4 CX BOARD (HV & XBR)
Horizontal Frequency
15.534KHz
31.5KHz
45KHz
33.75KHzz
R
Q9009 2 V-IN
IC9001
Q9010
6 12V
IK
7
Q9007
10 200V
G
V-IN
2
IC9002
6
12V
IK
7
Q9015
10 200V
B
V-IN
2
Q9011
6 12V
IC9003
7
Q9013 IK
10
200V
48
5. DA-4 & DA-4X Video Processing
R
12
G
12
B
12
C31P15-5-2 1524
CRT
11/12/02