Sharp 76GF-63 (serv.man4) Service Manual ▷ View online
2
76GF-63H
Use this page to keep any special servicing information as Technical Report (Bulletin), Technical Information, etc.
If only part number changes are required, just change part number directly the part number in the Parts Listing Section.
If you need more information, please refer to the Technical Report (Bulletin).
If only part number changes are required, just change part number directly the part number in the Parts Listing Section.
If you need more information, please refer to the Technical Report (Bulletin).
SERVICE MANUAL UPDATE LOG SHEET
Part No.
Technical Report No.
Technical Bulletin No.
Technical Bulletin No.
Cause / Solution
Page No.
Application
Data /Serial No.
Data /Serial No.
3
76GF-63H
ELECTRICAL SPECIFICATIONS
•
Power Input .......................220V-240 Volts AC 50Hz
•
Power Consumption
•
Audio Power Output Rating
Speakers
Left / Right........................................ 6 x 12cm
Centre.............................................. 6 x 12cm
Centre.............................................. 6 x 12cm
•
Aerial Input Impedance
•
Tuning Ranges..............45.75MHz thru 855.25 MHz
•
Intermediate frequency.............................
.38.9MHz
•
Adjacent Sound Carrier Trap
..................40.9MHz
•
Sound Carrier Trap
...............................32.9MHz
VHF/UHF...........................75 ohm Unbalanced
CATV Special Channels
Normal Operating..................................105W
Stand-by Operating.............................. ..1.3W
Stand-by Operating.............................. ..1.3W
Internal Left Speaker.....................10W (MPO)
Internal Right Speaker..................10W (MPO)
Internal Centre Speaker...........10W (MPO)
Internal Right Speaker..................10W (MPO)
Internal Centre Speaker...........10W (MPO)
•
White Level
Set brightness control to get total picture tube cathode current of 600 milliamperes under no signal condition.
Maximum necessary correction of each picture tube cathode current to get 8900 degrees K-20 MPCD screen
temperature should not exceed 15% of its original value.
X=0.290 Y=0.284
Maximum necessary correction of each picture tube cathode current to get 8900 degrees K-20 MPCD screen
temperature should not exceed 15% of its original value.
X=0.290 Y=0.284
WARNING
The chassis in this receiver is partially hot. Use an isolation transformer between the line
cord plug and power receptable, when servicing this chassis.
To prevent electric shock, do not remove cover. No user-serviceable parts inside. Refer
servicing to qualified sercice personnel.
cord plug and power receptable, when servicing this chassis.
To prevent electric shock, do not remove cover. No user-serviceable parts inside. Refer
servicing to qualified sercice personnel.
Convergence.........................Self Converging System
Focus....................................Bi-Potencial Electrostatic
Sweep Deflection...........................................Magnetic
•
Adjacent Picture Carrier Trap
................30.9MHz
Specifictions are subject to change without prior notice.
4
76GF-63H
IMPORTANT SERVICING NOTES
Only qualified service personnel are allowed to carry out maintenance and repair of this receiver.
SERVICING OF HIGH VOLTAGE SYSTEM AND CRT
It is important that the static charge is removed from the high voltage system when carrying out work
on the receiver. This can be achieved by connecting a 10K resistor (with a suitably insulated lead) from
the CRT cavity connector to the CRT ground tag. This must be carried out with the AC supply discon-
nected from the receiver.
Note the following:
on the receiver. This can be achieved by connecting a 10K resistor (with a suitably insulated lead) from
the CRT cavity connector to the CRT ground tag. This must be carried out with the AC supply discon-
nected from the receiver.
Note the following:
•
The CRT in this receiver employs Integral Implosion Protection.
•
If the CRT has to be changed it MUST be replaced with the correct type for continued safe
working
•
DO NOT lift the CRT by its neck.
•
When handing the CRT, ensure that shatterproof goggles are worn.
•
Ensure that the CRT is discharge before handling.
X-RAY
This receiver is designed to keep any x-ray emission to an absolute minimum. Some fault conditions
and servicing procedures may produce potentially hazardous x-ray radiation levels. This is a problem
when in close proximity to the receiver for long periods of time. To reduce any risks associated with
this, please observe the following precautions:
and servicing procedures may produce potentially hazardous x-ray radiation levels. This is a problem
when in close proximity to the receiver for long periods of time. To reduce any risks associated with
this, please observe the following precautions:
1. When undertaking any servicing on this chassis, DO NOT increase the EHT to more than 33 KV,
(at a instantaneous beam current of 1600
(at a instantaneous beam current of 1600
µΑ).
2. Ensure that during normal operation the EHT does not exceed 32KV
±
1KV (at a beam current of
1600
µΑ).
This level has been preset in the factory. Always check that this level has not been ex-
ceeded
after carrying out any repair on the receiver..
3. DO NOT replace the CRT with any other type than that specified in the parts listing as this may
cause excessive x-ray radiation.
after carrying out any repair on the receiver..
3. DO NOT replace the CRT with any other type than that specified in the parts listing as this may
cause excessive x-ray radiation.
BEFORE RETURNING THE RECEIVER TO THE CUSTOMER
In addition to the above checks, the following should also be carried out before returning the receiver
to the customer.
to the customer.
1. Inspect all the leads to ensure that they are dressed correctly and that they are not obstructed or
pinched by any other parts.
2. Ensure that all protective devices are in good condition. These will include nonmetallic control
knobs, insulating fish papers, cabinets backs, compartment covers or shields, mechanical insulators,
etc.
pinched by any other parts.
2. Ensure that all protective devices are in good condition. These will include nonmetallic control
knobs, insulating fish papers, cabinets backs, compartment covers or shields, mechanical insulators,
etc.
5
76GF-63H
ADJUSTMENT PROCEDURES
All adjustments to this chassis, except for focus, are carried out in the service mode.
•••••
SERVICE MODE
The service mode is provided to enable the engineer to correctly set up the receiver to the CRT fitted in the set.
Note that these adjustments may vary from one receiver to another.
Note that these adjustments may vary from one receiver to another.
To enter the service mode, carry out the following procedure.
1. Connect a test pattern to the antenna terminal.
2. Tune the receiver to this signal.
3. Turn the receiver off using the mains switch.
4. Press volume down and channel up buttons on the
front of the receiver at the same time.
5. Keeping these buttons pressed, turn the mains on.
6. When the set starts up it will be in service mode.
7. Release the two buttons.
1. Connect a test pattern to the antenna terminal.
2. Tune the receiver to this signal.
3. Turn the receiver off using the mains switch.
4. Press volume down and channel up buttons on the
front of the receiver at the same time.
5. Keeping these buttons pressed, turn the mains on.
6. When the set starts up it will be in service mode.
7. Release the two buttons.
•••••
Use the channel up and down buttons to move between the options.
•••••
Use the volume control buttons to change the data.
•••••
To store the data, use the stand-by button on the remote control.
•••••
To exit the service mode, turn the receiver off using the mains switch.
When the service mode is entered the following On Screen Display appears
-SERVICE SOFTWARE AND HEXADECIMAL COUNTER DISPLAY:
SW ON XXXX SW OFF XXXX HOURS ON XXXX
SW ON XXXX SW OFF XXXX HOURS ON XXXX
The figures displayed in the XXXX locations are hexadecimal representations of the number of times that particular
function has been executed. For example if the hexadecimal number displayed after SW ON was 0E4A, this would
correspond to the receiver being turned on 3658 times.
function has been executed. For example if the hexadecimal number displayed after SW ON was 0E4A, this would
correspond to the receiver being turned on 3658 times.
Adjustment menu:
The following adjustments can be carried out in the service mode.
•
Horizontal Shift
•
East West Width
•
Pin Phase
•
Pin Amp
•
Corner Amplitude
•
Corner Symmetry
•
Vertical Linearity
•
Vertical Amplitude
•
S Correction
•
Vertical Shift
•
Red Gain
•
Green Gain
•
Blue Gain
•
Red Cut Off
•
Green Cut Off
•
Blue Cut Off
•
Alter NVM Page
•
Alter NVM Position
•
Alter NVM Value
•
Teletext Mix Mode Contrast
•
Teletext Contrast
•
OSD Contrast
•
DVCO Adjustment (Only NTSC)
•
DVCO Adjustment (Only PAL)
•
AGC Adjustment
•
AFT Adjustment
•
OPC Value
•
Auto Installation On/Off
Geometry Adjustments
All geometry adjustments are based on an internally generated test pattern as shown
in figure 1. When carrying out any of the above geometry adjustments, use the inter-
nally generated test pattern for guidance.
in figure 1. When carrying out any of the above geometry adjustments, use the inter-
nally generated test pattern for guidance.
Fig.1
CH
4
5
