JVC AV28H20EUS Service Manual page 17

ADJUSTMENTS
CHECK ITEM
Measuring
Item
instrument
B1 Signal
Power Supply generator
check
DC voltm eter
Remote
control unit
High Voltage Signal
check generator
DC volunteer
Remote
control unit
VCO check Remote
control unit
IF SE RVICE ME NU
1. VCO
2. AT T ON/O FF
1-2 : SELECT
VCO (CW)
MA IN
T OO HIG H
AB OVE REF
JUST REF
BELO W RE F
T OO LOW
Test point Ad justment part
TP-91(B1) 1.RGB BLK
TP-E(# # # # )
[X connector
on POWER
DEF PWB]
CRT anode 1.RGB BLK
Chassis
GND
1. VCO
(Do not move)
i : EXIT
****MHz
i : EX IT
No. 51945
Description
1. Receive a any broadcast.
2. Push the "ZOOM" key and s elect the FULL mode.
3. Select 2. V/C from the SERVICE MENU.
4. Select 1. RGB BLK with function UP / DOWN ( / ) key.
5. Press the function + ( ) key to find the cut off screen (Black
screen).
6. Connect a DC voltmeter to TP-91(B1) and TP-E(#).
7. Make sure that the voltage is DC139.9 ±2.0V.
8. Press the function – ( ) key to return to service menu..
1. Receive a any broadcast.
2. Push the "ZOOM" key and s elect the FULL mode.
3. Select 2. V/C from the SERVICE MENU.
4. Select 1. RGB BLK with function UP / DOWN ( / ) key.
5. Press the function + ( ) key to find the cut off screen (Black
screen).
6. Connect a DC voltmeter to CRT ANODE and chassis GND.
7. Make sure that the voltage is DC 31.0kV
8. Press the function – ( ) key to return to service menu.
" Under normal c onditions, no adjustment is required.
" Confirmation adjustment.
1. Select 1.IF from the SERVICE MENU.
2. Then select 1.VCO from the IF SERVICE MENU.
3. Receive any broadc ast.
4. Check the arrow ( ← ← ← ← ) position between the ABOVE REF . and
BELOW REF.
AV32H20EUS
AV28H20EUS
AV28H20EUB
+1kV
.
-1.5kV
17