Sony KV-36XBR450, Service Manual

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KV-32HS20/36HS20/36HS20H/32XBR450/36XBR450/36XBR450H
SECTION 3: SAFETY RELATED ADJUSTMENTS
3-2. B+ MAX CONFIRMATION
Standard ............................................................................ 135.3 ± 1 VCD
Check Condition:
AC input voltage: ........... 120 (± 2) VAC at Board Adjustment Process
................................................ 130 (± 2) VAC at QC
... 120 (± 2) VAC at Overall Adjustment (after aging)
Note : If using a stabilized power supply, make sure that the distortion
factor is 3% or less.
Setting mode: ............................................................................ Full mode
Signal input:.................................................. Cross-hatch of NTSC at QC
Initial setting:...........................................................Reset condition at QC
Confi rm point: ........................................ Across C6544 for B+ of D Board
3-1. X RV8001, RV8002 CONFIRMATION METHOD AND HV SERVICE ADJUSTMENTS
3-3. HV SERVICE FLOWCHART
Is RHT
Changed?
Is D-Board
Replaced?
Replace RV8001, RV8002 and RV8003 (Board provided with RV8003) with the
same value:
HV project adjust and inspection
1. Turn RV8001 and RV8003 (only applicable when RV8003 is used in the circuit)
fully counter-clockwise.
2. Turn set on with black video signal then adjust RV8002 slowly to obtain
35.5kV ± 0.2kV.
3.
Case 1
(Board provided with RV8003):
- Turn RV8001 (coarse adjust) clockwise slowly until hold down operation
initially activates.
- Turn the set off and turn back RV8001 approximately 1/16 of a turn, then turn
the set back on.
- Turn RV8003 (fine adjust) slowly clockwise until hold down operation initially
activates.
Case 2
(Board NOT provided with RV8003):
- Turn RV8001 clockwise slowly until hold down operation initially activates.
5. Adjust RV8002 clockwise, then turn the set on. Change video to white field then
slowly turn RV8002 counter-clockwise to get 35.0 ± 0.2kv. Confirm set does
NOT TURN OFF at this condition. If yes, then repeat from step 1 again.
6. Finally, set back RV8002 to 31.50kv + 0.2kv at video cut off (black video).
Start
No
Yes
Change any
or
marked parts
Yes
No
Yes
No
Yes
Is +B, Vd and
hold down
confirmed?
Finish for
hold-down
check
Start from
the beginning.
CB, Vd and check hold-down on the D board video with no signal (standard
reset mode) as follows:
1. CB across C6544 to make sure that it is 135.3 ± 1 Vdc.
2. Confirm Vd at pin 2 CN5506 or at TP-Vd for 4.3V < Vd < 4.65 Vdc.
3. Apply 5.5 ± 0.3 Vdc at pin 2 of CN5506, then confirm that set holds down.
If all adjustments are complete, then seal and secure RV8001, RV8002 and
RV8003 (boards using RV8003) with epoxy to prevent any possible
misadjustment by non-trained technical service.