Sharp 21GT-22, Service Manual

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25
21GT-22
DESCRIPTION OF SCHEMATIC DIAGRAM
SAFETY NOTES:
1. DISCONNECT THE AC PLUG FROM THE AC OUTLET BEFORE
REPLACING PARTS.
2. SEMICONDUCTOR HEAT SINKS SHOULD BE REGARDED AS
POTENTIAL SHOCK HAZARDS WHEN THE CHASSIS IS OP-
ERATING.
IMPORTANT SAFETY NOTICE:
PARTS MARKED WITH “
å
” ( ) ARE IMPORTANT FOR
MAINTAINING THE SAFETY OF THE SET. BE SURE TO RE-
PLACE THESE PARTS WITH SPECIFIED ONES FOR MAINTAIN-
ING THE SAFETY AND PERFORMANCE OF THE SET.
SERVICE PRECAUTION:
THE AREA ENCLOSED BY THIS LINE ( ) IS DIRECTLY
CONNECTED WITH AC MAINS VOLTAGE.
WHEN SERVICING THE AREA, CONNECT AN ISOLATING TRANS-
FORMER BETWEEN TV RECEIVER AND AC LINE TO ELIMINATE
HAZARD OF ELECTRIC SHOCK.
NOTES:
1. The unit of resistance “ohm” is omitted.
(K = 1000 ohms, M = Meg ohm).
2. All resistors are 1/16 watt, unless otherwise noted.
3. All capacitors are
µ
F, unless therwise noted. (P =
µµ
F).
VOLTAGE MEASUREMENT CONDITIONS:
1. Voltage in parenthesis measured with no Signal.
2. Voltages without parenthesis measured with PAL Colour-Signal.
3. All the voltages in each point are measured with high impedence
volt-meter.
WAVEFORM MEASUREMENT CONDITIONS:
1. Colour bar generator signal of 2.0V peak to peak applied at Base
of Video Buffer Amp. Q254.
2. Approximately 4.0 V AGC bias.