Philips PR1906C121, Техническая сервисная информация

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J8 CHASSIS SERVICE ADJUSTMENTS
Service Adjustment Notes:
REQUIRED TOOLS FOR SERVICING
Isolation Transformer
Multimeter
Oscilloscope
High Voltage (100:1) Oscilloscope Probe
Sencore VG91 Universal Video Generator
Caution: The J8 chassis incorporates a "hot" ground system. Always use a separate isolation
transformer when applying power to the exposed chassis.
Unless Otherwise Specified:
1. All service adjustments are "hot" voltagewise. For maximum safety, ensure the use of properly
insulated tools.
2. Refer to the J8 Main Chassis Printed Circuit Board for location of test points and adjustable
components.
3. Grid Locations (Ex.: D-3) next to the reference numbers for components refer to the Main Chassis
Printed Circuit Board.
Focus Adjustment
1. Tune the set to a local or cable station.
2. Adjust the Focus Control (located on the upper part of the flyback transformer) for best picture details
at high light conditions.
Degaussing the Television
1. Position the television so that the screen faces the direction it will be facing when in use.
2. Ensure the set is turned off.
3. Move a degaussing coil in a circular motion slowly around the sides and front of the set.
4. Continue this motion while withdrawing the degaussing coil at least six feet from the television, and
then disconnect the degaussing coil from its power source.
Service mode
Introduction
The service mode is a combined Service Default Mode (SDM) and Service Alignment Mode (SAM). This
service mode is Called SDAM. When the television is in SDAM, all normal features (such as volume
control and direct channel access) are available. In service mode there will be an "S" displayed (in green)
at the top right of the screen. All other Service OSD’s will also be in green.
Error buffer
Error codes will indicate failures in the television.
A unique error code is available for:
•
activated protection
•
failing I2C device
•
general I2C error
•
RAM failure (e.g. internal RAM of microprocessor)