3-1
3.1 PREPARATION
(1) Precaution
This model does not contain adjustment controls (VR).
General deck system, camera system and monitor system
adjustment are not required. However, if MAIN board need
replacement, please use original EEP ROM on to new
board. Then adjustment are not required. And if parts such
as the following need replacement, special computerized
adjustment are required. 3.4.1 ELECTRICAL ADJUST-
MENT WITH PERSONAL COMPUTER is setup and it ad-
justs using a service support system. Please contact to
JVC Service for detail information.
• OP BLOCK
• EEP ROM (IC102 of MAIN board)
• MONITOR
In the event of malfunction with electrical circuits, trouble-
shooting with the aid of proper test instruments most be
done first, and then commence necessary repair, replace-
ment and adjustment, etc.
a) In case of wiring to chip test points for measurement,
use IC clips, etc. to avoid any stress.
b) Since connectors are fragile, carefully handle them in
disconnecting and connecting.
c) Short circuit between operation unit and DECK chas-
sis.
(2) Required test equipment
a) Color TV monitor.
b) DC power supply
c) Oscilloscope (dual-trace type, observable 100 MHz
or higher frequency)
• It is recommended to use one observable 300 MHz
or higher frequency.
d) Digital voltmeter
e) Frequency counter (with threshold level adjuster)
f) Personal computer
NOTE:
This model uses a dry cell as power supply. (can not
use AC adapter.)
Therefore, when adjusting, use DC POWER SUPPLY
and supply 6.3V to JIG connector.
SECTION 3
ADJUSTMENT
SERVICE
SUPPORT
SYSTEM
RS232C
COM PORT
PC CABLE
PERSONAL
COMPUTER
MENU
DC POWER
SUPPLY
DC6.3V
GND
COVER(JIG)
JIG CONNECTOR
CABLE
CN25
RED
TO RXD
WHITE
BLACK
TO TXD
TO BATT+
TO GND
TO GND
JIG CONNECTOR
COMMUNICATION CABLE
(3) Connection
When adjusting, connect each required equipment(s)
shown in figure.
Fig. 3-1-1
