Quasar SP-2725F, Руководство по обслуживанию

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Schematic Notes
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P
ARTS
L
IS
T
SCHEMATIC NOTES
1.
Resistors are carbon 1/4W unless noted
otherwise.
2.
Capacitors are ceramic 50V unless noted
otherwise.
3.
Coil value notes is inductance in
µ
H.
4.
Test point indicated by ; Test point but no
pin .
5.
Components indicated with are critical
parts and replacement should be made
with manufacture specified replacement
parts only.
6.
(BOLD LINE) indicates the route
of B+ supply.
7.
The schematic diagrams are current at
the time of printing and are subject to
change without notice.
8.
Ground symbol indicates HOT
GROUND CONNECTION;
indicates COLD GROUND.
NOTE:
All other component symbols are
used for engineering design
purposes.
WAVEFORM MEASUREMENTS
1.
indicates waveform measurement.
(Measurement can be taken at the best
accessible location in common to the
indicated point.)
2.
Taken with an NTSC signal generator
connected to the antenna terminal.
(NTSC color bar pattern of 8 bars of EIA
colors, 100 IRE white and 7.5 IRE black.)
3.
Customer Controls (Picture/Audio Menu) are
set to Normalize. Volume is set to “MIN”.
4.
All video and color waveforms are taken
with a wideband scope and a probe
with low capacitance (10 to 1). Shape
and
peak altitudes may vary
depending on the type of Oscilloscope
used and its settings.
5.
Ground symbol shown on waveform
number indicates (Hot) ground lead
connection of the Oscilloscope.
CAUTION:
Incorrect ground connection
of the test equipment will result in
erroneous readings.
3
VOLTAGE MEASUREMENTS
1.
Voltage measurement:
- AC input to the Receiver is 120V.
NTSC (HD, 1125i & 525P when
applicable)
signal generator is
connected to the antenna of the
Receiver. (Color bar pattern of 100
IRE white and 7.5 IRE black.)
- All Picture and Audio adjustments are
set to Normalize.
TV ANT/CABLE - (Set-Up Menu) in
TV/ANT Mode
Volume - Min.
TV/Video SW - TV position
Audio Mode - Stereo
- Voltage readings are nominal and
may vary ±10% on active devices.
Some voltage reading will vary
with signal strength and picture
content.
- Supply voltages are nominal.
2.
Ground symbol indicates ground lead
connection of meter.
Incorrect ground connection will result
in erroneous readings.
CAUTION:
Incorrect ground
connection of the test equipment will
result in erroneous readings.
IMPORTANT SAFETY NOTICE
THIS SCHEMATIC DIAGRAM INCORPORATES SPECIAL
FEATURES THAT ARE IMPORTANT FOR PROTECTION FROM
X-RADIATION, FIRE AND ELECTRICAL SHOCK HAZARDS.
WHEN
SERVICING IT IS ESSENTIAL THAT ONLY
MANUFACTURERS SPECIFIED PARTS BE USED FOR THE
CRITICAL COMPONENTS DESIGNATED WITH A
IN THE
SCHEMATIC.
B
E
C
CHIP TRANSISTOR
LEAD DESIGNATION
Values for components noted in schematics are subject to change without
any notice or obligation, so please check parts list for component value or
part number
Important notice: