JVC AV-N29220 Service Manual page 16

AV-N29220
■ ■ ■ ■ ADJUSTMENTS
B1 POWER SUPPLY
Measuring
Item
instrument
Check of DC Voltmeter TP-91 (B1)
B1 POWER
SUPPLY
ADJUSTMENT OF VIDEO / DEF. CIRCUIT
Measuring
Item
instrument
IF VCO Signal
adjustment generator
TOO HIGH
ABOVE REFERENCE
BELOW REFERENCE
TOO LOW
SYNC :
RF. AGC
adjustment
FOCUS Signal
adjustment generator
16
Test point Adjustment part
TP-E(" " " " )
Test point Adjustment part
CW TRANSF. (T131)
[VCO(CW)] MODE
YELLOW
YES
EXIT BY
EXIT
IT
No.19 RF AGC
FOCUS VR
[In HVT]
1. Receive a black-and-white signal.
2. Connect the DC Voltmeter to TP-91 (B1) and TP-E( " " " " ).
3. Confirm that the voltage is DC134V
" Under normal conditions, no adjustment is required.
1. Receive a NTSC broadcast. (use channels without offset
frequency).
2. Select the VCO(CW) mode from the SERVICE MENU.
3. Confirm the color change (yellow) from " TOO HIGH " to " TOO
LOW " by CW TRANSF. and " SYNC : YES " being shown on the
screen. Then, adjust
REFERENCE " mark turns yellow and confirm again " SYNC :
YES " being shown on the screen.
1. Receive a broadcast.
2. Select "No.19 RF AGC" of the PICTURE MODE.
3. Press the MUTING key and turn off color.
4. With the MENU LEFT key, get noise in the screen picture. (0 side
of setting value)
5. Press the MENU RIGHT key and stop when noise disappears
from the screen.
6. Change to other channels and make sure that there is no
irregularity.
7. Press the MUTING key and get color out.
1. Receive a crosshatch signal.
2. While looking at the screen, adjust FOCUS VR so that the
vertical and horizontal lines will be clear and in fine detail.
3. Make sure that the picture is in focus even when the screen gets
darkened.
No. 51833
Description
+2V
.
-2.5V
Description
" BELOW
CW TRANSF. until