– 9 –
4. Adjustment Procedure
8
Refer to the Location of the Test Points and
Adjusting Controls on the page 11.
3
Power Board
(1). +5V Adjustment
Test Point:
TP16 (+5V)
Main Board
Adjust:
VR2 (+5V)
Power Board
8
Turn on the power.
8
Connect the Digital Voltmeter to TP16.
8
Adjust VR2 to obtain 5.05 ± 0.05 V.
3
Main Board
(2). Real Time Clock Frequency Adjustment
Test Point:
TP21 (REAL TIME CLK)
Main Board
Adjust:
CT21 (REAL TIME CLK)
Main Board
8
Connect the Frequency Counter to TP21.
8
Adjust CT21 to obtain 32768.5 ± 0.03 Hz.
Note: This Adjustment should be done within 2 minutes
after turning on the power.
(3). Frame Memory Controller Frequency Adjustment
Test Point:
TP801 (FRAME MEMORY CLK) Main Board
Adjust:
CT801 (FRAME MEMORY CLK) Main Board
8
Connect the Frequency Counter to TP801.
8
Adjust CT801 to obtain 27 MHz ± 100 Hz.
(4). Audio PLL Adjustment
Test Point:
TP802 (PLL)
Main Board
Adjust:
CT802 (PLL)
Main Board
8
Connect the Digital Voltmeter to TP802.
8
Adjust CT802 to obtain 1.65 ± 0.1 V.
(5). Multiscreen Output Level Adjustment
Test Point:
Multiscreen Output Connector Rear Panel
Adjust:
VR751 (MULTI OUT)
Main Board
8
Connect the terminated Oscilloscope with 75
Ω
to the
Multiscreen Output Connector.
8
Adjust VR751 so that the H-Sync Level becomes 300 ± 15
mV as shown in Fig. 4-1.
Fig 4-1
(6). Record Output Level Adjustment
Test Point:
Spot Output Connector
Rear Panel
Adjust:
VR701 (REC OUT)
Main Board
8
Supply the Colour Bar signal to the Video Input Connector
1.
8
Set the position of the SW11 on the Main Board to SUB
side.
8
Connect the terminated Oscilloscope with 75
Ω
to Spot
Output Connector.
8
Adjust VR701 so that the H-Sync Level becomes 300 ± 15
mV as shown in Fig. 4-1.
(7). Decoder Clamp Level Adjustment
Test Point:
TP601 (CLAMP-1)
Main Board
TP602 (CLAMP-2)
Main Board
TP603 (CLAMP-3)
Main Board
Adjust:
VR551 (CLAMP-1)
Main Board
VR601 (CLAMP-2)
Main Board
VR651 (CLAMP-3)
Main Board
8
Connect the Digital Voltmeter to TP601.
8
Adjust VR551 to obtain 0.60 ± 0.02 V.
8
Change the connection of the Digital Voltmeter to TP602.
8
Adjust VR601 to obtain 0.60 ± 0.02 V.
8
Change the connection of the Digital Voltmeter to TP603.
8
Adjust VR651 to obtain 0.60 ± 0.02 V.
3
Analog Board
(8). Decoder 1 and 2 Input Level Adjustment
Test Point:
Spot Output Connector
Rear Panel
Adjust:
VR611 (DECODER-1)
Analog Board
VR621 (DECODER-2)
Analog Board
8
Supply the Stairstep signal (5 Steps, Chroma off) to the
Video Input Connector 1.
8
Confirm the Position of SW11 on Main Board is SUB side.
8
Connect the terminated Oscilloscope with 75
Ω
to the Spot
Output Connector.
300
±
15 mV
