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Date: 10/02/98    R762120

G2+DIAGNOSTIC

R762120

8

Block diagram

762120_B.drw

4XDGUXSOHU

(+7WRVSOLWWHU

)RFXVYROWDJH5
)RFXVYROWDJH*
)RFXVYROWDJH%

)RFXVXQLW

*YROWDJH5

*YROWDJH*

*YROWDJH%

-

+

084

1

*YROWDJHVWDELOL]HU

3

-

+

084

1

9UHI

9

9

)URP(+7

PRGXOH

-

+

084

1

-

+

084

7

6)

9

9

+7+'

9

9 9

6)

+7+'

&219

9

&219

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9ROWDJHGLDJQRVWLF

Monitoring  of the +230V and the -170V

Q203

+Conv’

+30V

HTHD

-

+

393

1

-

+
393

7

+30V

Z197
5V6

Vref

Q208

Q227

+Conv’

+30V

On Horizontal Deflection
module

L high freq
H low freq

+30V

level detector

Overvoltage protection

to SF line 

(J1-8)

G2

Killer

Summary of Contents for R762120

Page 1: ......

Page 2: ...D IS HOT TO AC THIS POWER SUPPLY LIKE THE HIGH VOLTAGE POWER SUPPLY DOES NOT USE A LINE ISOLATION TRANSFORMER MEANING A PORTION OF THE CIRCUITRYISHOT TO LINEANDSHOULDBETREATEDWITHCAUTION Rev 01 CONV SCAN FAIL 17V 30V 17V 230V HTHD 17V 9V 170V R762120S Voltage diagnostic CONV Overvoltage ...

Page 3: ......

Page 4: ......

Page 5: ...N G R E F P rim a ry S e co n d ary Q 101 P 7 P 1 P 6 F oc us C o n v C o n v 393 1 15V F 1 90 F 1 91 F 1 92 C o n v 1 2 6 5 4 30 V Q 2 0 3 C o n v 3 0V H TH D 393 1 393 7 30 V Z 1 9 7 5 V 6 V ref Q 2 0 8 Q 2 2 7 C o n v 3 0 V O n H o rizo n ta l D e fle c tio n m o d u le L h ig h fre q Hlo wfre q 30 V 1 7 M IC 2 1 7 7 6 2 1 2 0 _ A d rw le v e l d e te c to r O v e rvo lta g e p ro te c tio n ...

Page 6: ...084 1 9UHI 9 9 URP 7 P RGXOH 084 1 084 7 6 9 9 7 9 9 9 6 7 2 19 9 219 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9ROWDJH G LDJQRVWLF M onitoring of the 230Vandthe 170V Q 2 0 3 C o n v 3 0 V H T H D 3 93 1 3 93 7 3 0 V Z 1 9 7 5 V 6 V re f Q 2 0 8 Q 2 2 7 C o n v 3 0 V O nH o rizo n ta l D e fle c tio n m o d u le Lh ighfre q Hlo wfre q 3 0 V le v e l d e te cto r O ve rv o lta g e p ro te ctio n toSFline J1 8 G ...

Page 7: ...onthe 15V derivedfromthe 17M deliveredbythe first or main SMPS and the 300VM Thetransformerandassociatedrectifiercircuitsprovidethe FOCUS CONVand the CONV for the feedback control loop discussed hereafter B Control loop Feedback Adaptation Toobtainatrackingwiththelinefrequency aportionofthe HTHDvoltageisapplied to the base of Q208 Themainloopisrealisedbyapplyingthe CONV voltagetothebaseofQ203 thee...

Page 8: ...20V with P1 we also have a stable G2 voltage at the sliders That 1020 volt point is sensed with the divider R15 R13 P1 Since the Vref is 10volt the output of the OPAMP will change until pin 13 is also at 10 volt Any voltage difference due to a change of the 1020 volt is adjusted by Q2 which will feed a current from to the negative output of the OPAMP via the voltage dropping Q2 transistor Note tha...

Page 9: ...ns necessary for working on HIGH VOLTAGE equipment have been observed Alignment WARNING The power must be OFF before removing any connector from circuit board or unit Failure to do so may result in severe damage to the projection unit Turntheprojectoroff Put the module on the extension boards Connect to the VIDEO input e g an electronic colour test video signal Switch the projector in the VIDEO MO...

Page 10: ...justment of the black balance P2 B P3 G P4 R Observe the bars on the screen If any trace of color appears on the black or white bars then perform the following adjustments in low ambient light Cover the blue and the red lens with the lenscap Short circuit the two pins on the top side of the respective colour driver see illustration AdjusttheGreenG 2controlP3until the green raster is just visible o...

Page 11: ...n adjust the black balance Red cut off and Blue cut off in theRandomaccessadjustmentmode slightly to eliminate any trace of colour Re adjust brightness and contrast for optimum picture There should be no coloration between shades of gray Re adjust color control at normal Adjustment procedure ...

Page 12: ...19025 D R BY255 1323A0 DO201 1 D185 R1319025 D R BY255 1323A0 DO201 1 D280 R131907 D R BY584 182085 SOD61A 1 D281 R131907 D R BY584 182085 SOD61A 1 D282 R131907 D R BY584 182085 SOD61A 1 D181 R131927 D R BY229 60007A TO220C 1 D182 R131927 D R BY229 60007A TO220C 1 D183 R131927 D R BY229 60007A TO220C 1 F176 R314143 F 5X20 F 2A H UL 1 F190 R314188 F TR5 T 4A L UL 1 F191 R314188 F TR5 T 4A L UL 1 F1...

Page 13: ... 10 02 98 R762120 G2 DIAGNOSTIC R762120 15 Spare parts 76 2120 R313525 R804832 R774323 R804834 R314143 R314516 R722276 R366988 FuseF190 R3141188 Fuse F176 FuseF191 R3141188 FuseF192 R3141188 R804614 R803607 ...

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