Saturday, March 12, 2016

Viewsonic N3752W-1M - Service Mode - Firmware update - DDC update - Audio Amp and DC to DC converter Schematic

Viewsonic Model No. VS11405-1M 37” LCD TV – Service Mode – Adjustments – Audio Amplifier and DC to Dc converter Schematic - How to upgrade the firmware
V-Chip Setting
V-Chip: Press ENTER, and the following screen appears.
V-Chip is transmitted from TV station to help parents monitor what their children watch.
According to the pre-set of factory, viewers can see all of the channels. However, setting V-Chip can block the appointed channels.
The factory default of the password is “0000”.
To enable parental control, input the password, press button to focus on OK key, and then press ENTER. (Select cancel if you want to exit.)
To set up parental control.
The factory default of the password is “0000”.
To enable parental control, input the password, press
button to focus on OK key, and then press ENTER. (Select cancel if you want to exit.)
Factory mode (Service Mode)
Press ’POWER’, ‘’and ‘ENTER’ at the same time, then go into the FACTORY MODE.
EEPROM INITILIZATION
A.Timing: 1360*768@60Hz
B. Pattern: 16*12 pane
C. Press ’POWER’, ‘▲’and ‘ENTER’ at the same time, then go into the FACTORY MODE
D. Select EEPROM INITIAL and press ENTER. The act of EEPROM INITIAL is completed when EEPROM INIT disappeared.
COLOR TEMPERATURE ADJUSTING: PC MODE
A. Timing: 1360*768@60Hz.
B. Pattern: 16 grey scale.
C. LCD TV should be run-in and warmed up for at least 30 minutes.
D. Make sure the distance between SENSOR of the CA110 and the LCD TV is about 20cm.
E. Color Temperature adjusting.
under the picture 16 grey scale of VGA source, select WHITE BALANCE and press ENTER, The color warm will auto adjust. The act of WHITE BALANCE is completed when the picture is steady.
2.After adjusting, switch to FULL WHITE and check the value of each color.
Preset color for N3752W
x=0.283±0.015.      y=0.297±0.015
3.Under the picture NTSC color bar of YPbPr source, select WHITE BALANCE and press ENTER, The color warm will auto adjust. The act of WHITE BALANCE is completed when EHITE BALANCEL disappeared.
4.After adjusting, switch to FULL WHITE and check the value of each color.
Preset color for N3752W
x=0.283±0.015.      y=0.297±0.015.
DTV FUNCTION TEST
Make sure the power is OFF before installing your LCD TV.
A. Air TV: Connect the LCD TV to TV antenna with 75-ohm coaxial cable. Preset the air TV channels into memory with AUTO SCAN function when using an antenna TV system. This air input jack both support TV and DTV systems.
Besides, the TV system (NTSC) and DTV systems (ATSC) can be found by the scanning of “AIR” in the AUTO SCAN function.
B. Cable TV: Connect the LCD TV to the cable with CATV and Digital cable. Preset the cable TV channels into memory with AUTO SCAN function when using a cable TV system. The cable input jack both support CATV and Digital cable systems. Besides, the CATV system (cable TV) and Digital cable system (Clear QAM) can be found by the scanning of “Cable” in the AUTO SCAN function.
YPbPr, S-VIDEO, AV, TV, DTV’S FUNCTION TEST
A. Input YPbPr, S-VIDEO, AV , TV, DTV’S signal and check.
B. Input USA air channel (TABLE 1) and USA CATV channel for TV channel.
C. Under YPbPr MODE, Make sure the 408i, 480P, 720P, 1080i is right.
DDC key-in procedure
Every time after replacing the main board, you have to do the DDC key in.
2. If you find the DDC does not conform to the LCD TV, you have to do the DDC key in.
Equipment Needed
> N3752W LCD TV
> DDC Card
> PC
> RS-232 cable
> Barcode Reader
> VGA Cable.
Setup Procedure
Connect VGA Card and DDC Card with RS-232 cable.
Barcode Reader connects with keyboard and PC keyboard port.
Connect DDC Card and N3752W LCD TV with VGA Cable.  (when key in DVI DDC information, use VGA transform to DVI port )
Connect Power Cord to N3752W LCD TV.
Run DDC exe.
Choose model number then Press “ENTER” key.
Input bar code
Press “ENTER” key, then the successful picture is as follows. “DDC DOWNLOED OK.
Exit program.
HDMI DDC Key In Procedure
There are three EDID files for the different HDMI connectors. So you must be download the different EDID into each HDMI connector.
Connect HDMI Card and DDC Card with RS-232 cable.
Barcode Reader connects with keyboard and PC keyboard port.
Connect DDC Card and N3752W LCD TV with HDMI Cable.
Connect Power Cord to N3752W LCD TV.
Run DDC.exe.
Choose model number then Press “ENTER” key. “DDC DOWNLOD OK.
Exit program.
Main Firmware Upgrade Procedure
When you receive the returned LCD TV, check whether the firmware version is the latest. If not, please do the following procedures to upgrade it to the latest version.
Equipment Needed
> N3752W LCD TV
> Fixture for Firmware Upgrade
> VGA Cable
> PC (Personal Computer)
> Firmware Upgrade Program
> One additional LCD TV for checking the program execution. 
Installing the USB device driver. 
The USB driver will be upgraded if necessary. ["PL-2303 Driver Installer.exe"]
Insert the USB to RS232 Download Board to PC’s USB port. Then you can found the USB Device detected and follow Windows comments to finish the Driver install.
Execute the Mtktool to start download the file. The Mtktool program will be upgraded if necessary. ["MtkTool Auto BaudRate.exe"]
The Mtktool Operate
Select Platform: MT8105, MT1389, MT8202 or MT8205.
Select COM port. Depends on the COM port assigned in System Device Manager.
Select Baud Rate. 115200x 8 (Suggestion)
Enable the USB Bridge.
Browsing the File to download.
Press Upgrade to download file.
Notes
1. The Baud Rate is auto setting if mismatch found between your platform and Mtktool.
2. You can slow down the baud rate if some Flash memory cannot works properly in high-speed download.
3. Call the MediaTek contact window if any problem found like unsupported Flash Type or fail to download.
DC to DC converter schematic
Audio Amplifier Circuit diagram
AUDIO FUNCTION TEST
A. Audio input includes PC AUDIO IN, S-VIDEO/AV AUDIO IN and YPbPr AUDIO IN.
B. Under PC MODE, input PC AUDIO signal, checks whether the action of AUDIO IN is right.
C. Under S-VIDEO/AV MODE, input L/R AUDIO signal, checks whether the action of AUDIO IN is right.
D. Under YPbPr MODE, input L/R AUDIO signal, checks whether the action of AUDIO IN is right.
E. Under HDMI MODE, checks whether the action of AUDIO IN is right.
F. Under DTV MODE, checks whether the action of SPDIF is right.
G. AUDIO OUT FUNCTION TEST: Under all patterns except PC pattern, The Audio output meets active extra speaker, examines whether the extra speaker makes the sound.