Sony KV27FV16 service manual Section Safety Related Adjustments, Preparation Before Confirmation

KV-27FV16/29FV16/29FV16C/32FS12/32FS16

SECTION 4

SAFETY RELATED ADJUSTMENTS

4-1. R564 CONFIRMATION METHOD

(HV HOLD-DOWN CONFIRMATION) AND READJUSTMENTS

The following adjustments should always be performed when replacing the following components which are marked with on the schematic diagram:

Part Replaced (	)	Adjustment ( )
DY, T505, CRT, IC501, C507,		HV HOLD-DOWN
C520, C505, C509, C515, T504,		R564
T503, C551, L510, C546, C537,
C547, D517, D518, D519, R560,
R561, R562, R563, R565, R566,
R567, R525	A Board
IC301	MA Board

Preparation Before Confirmation

1.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 BRIGHTNESS controls to maximum.

4.Confirm that the voltage between C546 (+) or TP503

and ground is more than 21.0 VDC (KV-27FV16/29FV16/ 29FV16C ONLY), 23.0 VDC (KV-32FS12/32FS16 ONLY).

Hold-Down Operation Confirmation

1.Connect the current meter between Pin 11 of the FBT

(T505) and the PWB land where Pin 11 would normally attach. (See Figure 1 on the next page.)

2.Input a dot signal and set PICTURE and BRIGHTNESS

to minimum: IABL = 1730 ± 100 ∝ A (KV-27FV16/29FV16/ 29FV16C ONLY), IABL = 2175 + 100/- 325 ∝ A (KV-

32FS12/32FS16 ONLY).

3.Confirm the voltage of A Board TP-600 is 135 ± 1.5 VDC.

4.Connect the digital voltmeter and the DC power supply via diode 1SS119 to C546 (+) and ground. (See Figure 1 on the 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 < 24.78 +0.0/-0.1 VDC - KV-27FV16/29FV16/ 29FV16C ONLY) (standard < 27.24 + 0.0/- 0.1 VDC - KV- 32FS12/32FS16 ONLY) .

8.Input a white signal and set PICTURE and BRIGHTNESS to maximum: IABL = 1730 ± 100 ∝ A (KV-27FV16/29FV16/ 29FV16C ONLY), IABL = 2175 + 100/- 325 ∝ A (KV-

32FS12/32FS16 ONLY).

9.Repeat steps 4 to 7.

Hold-Down Readjustment

If the setting indicated in step 2 of Hold-Down Operation Confirmation cannot be met, readjustment should be performed by altering the resistance value of R564 component marked with .

T505

FBT

ammeter

3.0 mA DC range

ABL + A -

IABL

4-2. B+ VOLTAGE CONFIRMATION AND ADJUSTMENT

Note: The following adjustments should always be performed when replacing the following components, which are marked with on the schematic diagram on the A Board.

A BOARD: IC601, PH601

1.Using a Variac, apply AC input voltage: 130 + 2.0/-0.0 VAC.

2.Input a monoscope pattern.

3.Set the PICTURE and BRIGHTNESS controls to minimum.

4.Confirm that the voltage of A Board TP-600 is <136.5 VDC.

5.If step 3 is not satisfied, replace the components listed above, then repeat steps 1–3.

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