Toshiba 29VH27E, Service Manual

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15.4.FOCUS ADJUSTMENTS
Inputs AC power
PAL B/G test pattern via RF input.
Outputs Picture tube drive.
Display Picture
Action Select TV mode and tune to the signal.
Adjust focus potantiometer (the upper pot on the rear side of the FBT transformer) for
optimum focusing drive.
15.5.SCREEN ADJUSTMENTS
Inputs AC power
PAL B/G Colour Bar test pattern via RF
Outputs 1/100 Oscilloscope probe to RGB cathodes on CRT baseboard.
NOTE: Ground pin of probe will be connected to 1
st
pin (GND) of the CRT socket.
Display RGB ratio
Action Select PAL B/G Colour bar pattern using the local test keyboard and the user remote
control unit.
Adjust all control functions (brightness, colour and contrast) to minimum settings.
Measure the most sensitive cathode
Adjust the screen potentiometer (lower pot on the rear side of FBT transformer) until
cathode voltage becomes 150V.
15.6.IF ADJUSTMENT FOR L’ MODE
Inputs AC power
38.9 MHz test pattern for PAL B/G, PAL-SECAM B/G or 39.5 MHz test pattern for PAL I
model. (90dBmV) to Z403 SAW filter input terminals 1 and 2.
Outputs Digital Voltmeter to AFC point. (pin22 of IC401)
Digital Voltmeter to AFC_L point. (pin14 of IC401
Display AFC Voltage.
Action Firstly adjust VL401 for 2.5±0.1 Volts. TV should automatically tune to a station when
search tuning is activated.
Adjust VR401 for 2.5±0.1 Volts at the AFC_L point.