Sony TRINITRON KV-20FS120 Service Manual

Also see for FD TRINITON VEGA KV-20FS120: Operating instructions Operating instructions Brochure Operating instructions Operating instructions

Contents

17KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120Hold-Down ReadjustmentIf the setting indicated in Step 2 of Hold-Down Operation Confi rmationcannot be met, readjustment should be performed by altering theresistance value of R565 component marked with X.+IABLABLT585FBTrange-Ammeter3.0 mA DCA3-2. B+ VOLTAGE CONFIRMATION ANDADJUSTMENTNote: The following adjustments should always be performed whenreplacing the following components, which are marked with Y on theschematic diagram on the A Board:A BOARD: Y IC600, PH6021. Using a Variac, apply AC input voltage: 130 + 2.0 / - 0.0 VAC.2. Input a DOT pattern at Q.C.3. Set the PICTURE and the BRIGHTNESS controls to minimum.4. Confi rm the voltage of A Board between TP-23 & Ground is =135.6± 1VDC.5. If step 4 is not satisfied, replace the components listed above, thenrepeat steps 1 through 3.SECTION 3: SAFETY RELATED ADJUSTMENTS3-1. X R565 CONFIRMATION METHOD(HV HOLD-DOWN CONFIRMATION) ANDREADJUSTMENTSThe following adjustments should always be performed when replacingthe following components which are marked with Y on the schematicdiagram:DY, T585, CRT, IC001, IC561,IC600, C506, C507, C508, T511,L510, C588, L588, C566, C561,C563, D567, D568, D566, PH602,R567, R568, R565, R566, R562,R563, R561, R528……....A BoardHV HOLD-DOWNRV565Part Replaced (Y) Adjustment (X)Preparation Before Confirmation1. Using a Variac, apply AC input voltage: 120 ± 2 VAC.2. Turn the POWER switch ON.3. Input a white signal and set the PICTURE and BRIGHTNESScontrols to maximum.4. Confi rm that the voltage between C566 (+) or TP30 and groundis more than 97 VDC for 20”/21” models, or 105 VDC for 24”/25”models.Hold-Down Operation Confirmation1. Connect the current meter between Pin 11 of the FBT (T585) and thePWB land where Pin 11 would normally attach (See Figure 1 on thenext page).2. Input a dot signal and set PICTURE and BRIGHTNESS to minimum:IABL = 100 ± 100μA.3. Confi rm the voltage of A Board TP-23 is 135.6 ± 1VDC.4. Connect the digital voltmeter and the DC power supply via Diode1SS119 to C566 (+) and ground (See Figure 1 on next page).5. Increase the DC power voltage gradually until the picture blanks out.6. Turn DC power source off immediately.7. Read the digital voltmeter indication(standard < 117.0 VDC) for 20”/21” models(standard < 138.0 VDC) for 24”/25” models.8. Input a white signal and set PICTURE and BRIGHTNESS tomaximum: IABL = 1350 ± 100μA for 20”/21” models orIABL = 1650 ± 100μA for 24”/25” models9. Repeat steps 4 through 7.