Saturday, June 11, 2016

ONIDA 21BLACK FGL - 20XS - How to enter Service Mode – Adjustments

Service Mode 3G(UE-DLX)
The following display comes on the screen by pressing DISPLAY key and VSM key at the same time.
FACTORY
SERVICE MODE
Press CURSOR UP OR DOWN key to be in Service menu.
To select Service Menu parameters use CURSOR UP OR DOWN key and to adjust these parameters use CURSOR LEFT OR RIGHT key.
H-LINE
1) To get H-line press VSM and DISPLAY Simultaneously.
2) Press CURSOR UP KEY to get R CUTOFF.
3) Press '0' to get H-line.
4) To come out of H-line again press '0'
VSM PRESET
There are FOUR VSM
PRESETS.(CARTOON,FILM/POP,NEWS,)
For the setting of individual VSM PRESETS
1. Press VSM and DISPLAY at the same time.
2. Press CURSOR DOWN key to get the Setting for the VSM PRESET.
3. Press CURSOR DOWN key for the selection of each parameter.
4. Use CURSOR LEFT/RIGHT key for their setting as per the table given below.
5. Press VSM Key for selection of VSM PRESETS.
Adjustment Procedure
1) Switch ON the TV Set.
2) Select colour bar pattern {carrier frequency of 38.9MHz} from pattern generator.
3) Connect this signal to the input of Saw Filter(after disconnecting IF output of Tuner)
4) Connect Digital Multimeter to AFC out(pin no. 2 of VCD IC52771, IC201)
5) Adjust VCO coil in such a way that Digital Multimeter shows 4V(sudden change in voltage reading from 8V)
This voltage should be adjusted whenever there is sudden fall from 8V to 1V as shown
NOTE
# use non-metallic adjustment tool (eg~ceramic) for adjustment.
# Correct AFT voltage alignment can be confirmed by monitoring proper waveform at pin no. 38 of VCDIC 52771 IC no. 201./CRO can be also connected to Video OUT terminal.
Low light Adjustment 3G(UE-DLX)
1) Receive the monoscope pattern signal .
2) Select either R CUTOFF , G CUTOFF B CUTOFF in the Service menu.
4) Push 0 key on any mode to make a horizontal line.
5) Turn the screen knob (the Bottom of FBT) gradually from fully left to the right & search for the first appearing colour.
6) Adjust two colours except for the first colour which appears by the adjustment 5) to the white colour with the following 1~ 6 key.
7) Turn the screen knob so that a horizontal line appear slightly.
8) Change the normal screen by pushing 0 key again.
9) Receive the pedestal pattern signal
10) Readjust the Colour of the pattern to white colour by varying 1~ 6
High light Adjustment  3G(UE-DLX)
1) Receive the monoscope pattern signal .
2) Select R-DRIVE &/OR B DRIVE in the Service Menu.
3) Adjust R-DRIVE & B-DRIVE so that the white balance is at the directed value (Adjustment point “A”).
4) Check if the tracking of white balance from Low light till High light is good.
5) Receive the pedestal pattern signal .
6) Check if the white balance of low light is good. If the white balance of the low light is not good, adjust the low light again.
7) Receive the monoscope pattern signal.  Repeat step (4) onwards till perfect white balance is achieved in low light and high light patterns.
Bright Adjustment  3G(UE-DLX)
1) Receive the Black pedestal pattern signal .
2) Select Sub Bright in the Service Menu.
3) Adjust the Sub Bright so that the point of gradation value does not shine.
Note 
While entering in Service Menu ,by default it takes the values of VSM cartoon, hence the above parameter is adjusted with respect to cartoon condition.
Contrast Adjustment
1) Receive the Black pedestal pattern signal.
2) Connect the probe of the oscilloscope to Green cathode.
3) Select Sub Contrast in the Service Menu.
4) Adjust it so that the value between the dot line & white peak of the signal waveform as mentioned below to be the directed voltage as mentioned.
14" 70V
20/21” 80V
Colour Adjustment (PAL)
Receive the PAL colour bar pattern signal .
2) Connect the probe of the oscilloscope to green cathode.
3) Select Sub color in the Service Menu.
4) Adjust the Sub color so that the value between the white peak & blue as.
14/20/21” +3V
Colour Tint Adjustment (NTSC3.58,NTSC4.43)
Connect the NTSC Video Colour bar pattern signal  (White 75%) to Video input Terminal.
2) Connect the probe of the oscilloscope to BLUE CATHODE.
3) Adjust the Sub Tint so that the value between the white peak and Magenta is as.
14/20/21” +5V
Horizontal Centering
1) Receive the monoscope pattern signal.
2) Select H-Center 50 in Service Menu.
3) Adjust it so that H & H’ becomes equal as shown below . There is a separate H-centering for AV mode (50 Hz) also The same can be adjusted in AV mode also.
4) Connect the monoscope pattern signal (60Hz) to Video input terminal.
5) Select H-Center 60 in Service Menu adjust it so that H & H’ becomes equal.
RFAGC Adjustment
Method 1
1) Switch ON the TV set
2) Apply RF Input to tuner and select color bar pattern.
3) For Philips 5V tuner , input signal should be 60dbuV For Samsung 5V tuner input signal shoud be 70dbuV
4) Connect the multimeter to TP.AGC on main board near tuner
5) Adjust RFAGC till the voltage is 4Vdc
Method 2
1) Receive the PAL colour bar pattern signal (Input level is 75dBµV term)
2) Adjust RF AGC so that Noise is min, on picture or VIDEO OUT.
3) Receive the PAL halfcolour bar pattern signal (Input level is 80dBµV term)
4) Make sure that there is no beat on the picture.