Sony Trinitron PVM-14L2 - High Tension Regulator Confirmation; HV Protector Circuit Confirmation

3-2
PVM-14L2/20L2
3-2. High Tension Regulator Confirmation
1. Turn the POWER OFF.
2. Connect an electrostatic voltmeter to anode cap of
CRT tube.
Electrostatic voltmeter : It must have input impedance
of 2 x 10
9
Z and have already been calibrated.
(Example : Singer ESH-27X or ESH-23X)
3. Supply AC power voltage of 130 VAC to the unit and
turn the POWER ON.
4. Input the 480/60I all black signal, and adjust the
BRIGHT and CONTRAST knobs on the front panel to
their mechanical center positions.
5. Confirm that the high tension voltage value satisfies
the standard value.
Standard value : 23.5 ±1.5 kV (14 inch)
26.5 ±1.5 kV (20 inch)
3-3. Protection Circuit Confirmation
3-3-1. HV Protector Circuit Confirmation
1. Supply AC power voltage of 127 to 130 VAC to the
unit and turn the POWER ON.
2. Input the 480/60I all black signal, and adjust the
BRIGHT and CONTRAST knobs on the front panel to
MIN.
3. Confirm that the voltage between the D501 cathode
(TP502) and GND on the G board satisfies the standard
value.
Standard value : 20.0 VDC or more (14 inch)
23.5 VDC or more (20 inch)
4. Apply the following voltage between the D501
cathode and GND on the G board, and confirm that the
protector circuit is not activated.
23.1 to 23.5 VDC (14 inch)
27.1 to 27.5 VDC (20 inch)
5. Apply the following voltage between the cathode
(TP502) and GND of D501 on the G board, and
confirm that the protector circuit is activated and raster
disappears.
25.4 to 25.6 VDC (14 inch)
29.3 to 29.5 VDC (20 inch)