SECTION 3
ELECTRICAL ADJUSTMENT
3.1 ELECTRICAL ADJUSTMENT
3.1.1 PREPARATION3. Required adjustment tools
For detsails of special jigs necessary for adjustment, refer
1. Precaution
to page 1-2 and 1-3 of the Section 1.
This model does not contain adjustment controls (VR).
General deck system, camera system and monitor system
4. Setup for E. VF section adjustment
adjustment are not required. However, if MAIN board and
MONITOR board need replacement, please use original EReferring to OSEC. 1 DISASSEMBLY� and connect the E. VF
WIRE to CN12 of the MAIN board.
2 PROM on to new board. Then adjustment are not required.
And if parts such as the following need replacement, spe-
(LY20701)
cial computerized adjustment are required (Refer to sec.
3.1.1- 4). Please contact to JVC Service for detaile informa-
Bottom case assySerial No. label
tion.
Y OP block
Y EEP ROM (IC102 of MAIN board)
Y 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.Screw
Parts No.
1. In case of wiring to chip test points for measurement,LY20701
use IC clips, etc. to avoid any stress.Adjustment ltem : 3.2
2. Since connectors are fragile, carefully handle them in dis-
connecting and connecting.
Note:
3. Shortcircuit between operation un it and DECK chassis.Y This adjustmentalls into a special adjustment that requires
a personal computer. For details, refer to O3.1.1 Prepara-
2. Required test equipmenttion�.
1. Color TV monitor.
2. AC power adapter
3. Oscilloscope (dual-trace type, observable 100 MHz or
higher frequency)
* It is recommended to use one observable 300 MHz or
higher frequency.
4. Digital voltmeter
5. Frequency counter (with threshold level adjuster)
6. Personal computer
5. Connection for Service support system
Jig connector cableService Support System
CN25
RS232CCover(JIG)
COM PortExtention connector
MENU
NOTE: For supplying the power through the coupler by removing
the cover (for jig), use this extension connector double
for connecting the jig connector cable.
JIG CONNECTOR COMMUNICATION CABLE
to 10 pin
( RXD )RED
to 28 pin PC CABLE
( TXD )WHITE
to 8 or 5 or 4 pin
( GND )Personal ComputerBLACK
Fig. 3-1-1 Connection for Service support system
3-1 |
ACEC
