TV inspection

Views: 50     Author: Site Editor     Publish Time: 2022-09-20      Origin: Site

1. Preparation before inspection  

1) Determine the signal sources required by the TV test (such as various video, audio signals, WIFI signals, etc.)  

2) Determine the required test disk and external equipment (such as headphones, USB flash drives, etc.)  

3) Determine the voltage and frequency used  

4) Determine the socket used  

5) Determine whether the equipment is calibrated and whether the validity period is valid  

6) Determine the number of sets of test equipment that can be supplied  

7) Determine the test environment and equipment for Running test  

8) For CRT screen: the corresponding magnetic field house in the country where the TV is sold  

9) Please provide the specifications of the display  


Two, function check  

1) Test voltage should be rated voltage and frequency  


2) Security test  

(1) Shock test  

Check the default software and hardware versions, default country, default language, default time  

Connect each signal source, test each output port, and observe whether the played image and audio are normal.  

When changing different signal sources, we should do the camera test to see whether the image and audio are abnormal  

Test the buttons on the TV  

(2) Test each button of the remote control  

A TV, D TV(including Radio) check the total number of stations, check whether there is any leakage station.  

Channel conversion and AV/TV/ port conversion are normal  

Check the Smart Card jack and decryption function when using DTV  

Nokia Monitor Test to test the image quality and call the three primary colors, black and white five screen to check the highlights/dark spots.  

Test the connection line and other accessories in the color box  

3) Specific tests  

(1) Reference standard  

IEC: International standard  

UL: American standard  

Verify that all cables are connected as required before plugging in the power supply.  

Note: All input and output interfaces on the TV need to be checked  

(2) After the boot, do A TV, D TV(including Radio) search station check  

Check with the factory about the number of analog, digital and broadcast signals you can normally receive before searching the station.  Check whether there is any leakage during the test.  

When searching stations, it is necessary to search analog stations and digital stations respectively. The search time may take 10 to 30 minutes. You can focus on searching stations in advance before the test.  

When checking, search a good machine, not search a machine to partition  

(3) Check the function of each button on the TV in sequence to ensure that the button works properly and turn up the volume.  

Load the remote with batteries and use it to check your TV's function.  

Test each button of the remote control  

Check the function of each key of the remote control, each key should be responsive.  

Whether it has backlight function  

(4) Check first:  

Country of default  

The default language  

Software Version  

Hardware Version  

(5) Change the input signal sources in order to observe whether the images and audio played by the programs of each signal source are normal  

During conversion, there should be no bad phenomena such as crash, flower screen, color loss or abnormal image  

When changing different signal sources, we should do the camera test to see whether the image and audio are abnormal  

(6) Check the content  

4:3, 16:9 picture  

TV and radio programs on ATV, DTV  

Programs in all resolutions  

See if there are any trailing, residual images  

Pay attention to the selection of station, turn signal source time is abnormal (analog and analog mutual turn  

During conversion, there should be no bad phenomena such as crash, flower screen, color loss or abnormal image  

Select and watch a digital encrypted TV program (with a lock symbol) to determine if the CI card is functioning properly  

Check PIP picture-in-picture /CCD hidden caption Test /Teltext teletext function  

(7) R/L channel, stereo, Liyin, 5.1 channel stereo (R/L sound is installed or not, speaker has phase connection, R/L balance).  

(8) Set the sound to the silent state through the remote control, and stay for 2 seconds, listen to whether there is redundant noise, high frequency sound and other sound output.  

(9) Network TV: It is necessary to check whether the wired and wireless can be connected properly  

In the sound test, the volume of each machine is turned up to watch for howling and distortion  

(10) Attention should be paid to the accompanying sound check:  

The volume should be moderate  

There is no delay, intermittent, noise, distortion, buzzing, bottom noise, mechanical vibration and low or high frequency noise from components  

Normal phase  

Switch machine, turntable, no obvious impact sound;  

The accompanying sound should not interfere with the image, and there should be no accompanying sound crosstalk between the TV and AV audio input terminals.  

It is required that when tapping the chassis and switching between high and low voltage, the accompanying sound is normal, and there should be no intermittent, distortion and other phenomena  

(11) Check the quality of the display using one of the following methods:  

Run the Nokia Monitor Test software through the VGA port  

Check the monochrome picture, lion head pattern and color bar signal and grid signal from the factory signal center.  

Nokia Monitor Test contents  

Run the Nokia Monitor Test on the PC to check the specified picture quality.  

To ensure the consistency of the test, the "standard" image mode should be used)  

Screen to Test in Nokia Monitor Test:  

Main Screen  

Single color bar  

The left and right channels of the Speaker  

We mainly look at:  

a. The five circles have deformation and raw edges  

b. Nokia logo Check crosstalk  

c. In the color scale, there are 40 small blocks of red and blue, each of which should be clearly separated. In the green scale, there are 40 large blocks, each of which has two small blocks, and these 40 large blocks should be clearly separated.  

d. In grey scale, between 3% and 100% of the total 11 squares should be clearly separated.  

e. The bezels on each side of the overscan can be read "Re-overscan" and "tilt-tilt".  

f. Look at the graph distortion of each small square under the CRT screen (each square should be the same size).  

g. Click the "Color" bar next to www in the main interface to conduct each monochrome test to see if there are highlights/dark spots  

h. Observe each monochrome picture:  

i. Main observations in monochrome display:  

- Black screen for highlights  

- Look dark on the white screen  

- Other screens confirm whether it is a bright spot or a dark spot.  

- Can check the color purity and uniformity  

- Check for light leaks and speckled Mura under black screen.  

j. Examination of left and right vocal tract:  

When testing with a factory signal center, the following signals are also checked  

Test black, white, red, green, and blue monochrome images  

Lion head design  

Color bar signal  

Check of grid signal  

Right and left vocal tract  

The check content is the same as that of the Nokia Monitor Test  

If the teeth of a lion's head are clearly visible, the clarity is OK  

Clarity check area, number of clarity lines can be read (350, 400, 450 lines -- displayed reading x10)  

Sweep the inspection area and check the mark line of the swept line (generally to 7).  

Corner sharpness check area (the four small circles in the corner are the four corner sharpness check area, the CRT corner sharpness is worse than the central one)  

(12) 3D TV test:  

a. The picture should not flicker when watching  

b. Watch from multiple angles, up, down, left and right, to see a good 3D effect  

c. With good anti-crosstalk ability, no double shadow will be seen when watching  

d. Whether the picture is too dark  

(13) The cable inspection in the accessories: All the cables should be checked with the host, such as AV,RCA, USB, SCART, HDMI and so on.  It is recommended to check the accessories of each machine together with the main machine, and do not advocate separate inspection.  

(14) After confirming the completion of the above tests, shut down the machine with the remote control (the power supply of the host is not cut off), and listen to whether there is abnormal noise output.  

(15) After the inspection, the TV set should be reset to the factory setting. (This step can be carried out jointly by the workers.)  


4) Professional performance test (3 sets)  

(1) Warm-up before test:  

During the test, the TV should be set to Standard image mode and set to full-screen display. After 1 hour of operation, the test should be started after the performance is stable.  

(2) Infrared remote control front test  

Long-distance test: 8 meters in front of the sensor head  

Close test: 3 cm in front of the sensor head  

(3) Infrared remote control Angle test:  

The tester was 4.5 meters away from the TV to test whether the remote control and the TV receiving lens could work normally when the horizontal Angle was about 30°  

Test whether the TV can work normally at a vertical Angle of 15° up and down at a distance of 3 meters  

It can be divided into induction head test and remote control head test  

(4) Sensor head test: (The remote control is tested in four directions, and the remote control points to the origin of axis coordinates)  

(5) Transmitter head test: The remote control is tested in front of the Y-axis direction, the position of the remote control remains unchanged, and the receiving ability of the four directions of rotation is tested.  

(6) Power test when broadcasting TV programs  

a. Different test signals have different power  

b. Set the TV setting to default during the test  

c. ON MODE (AVERAGE) TESTING USING DYNAMIC.BROADCAST-CONTENT VIDEO SIGNAL. Remember to indicate the signal you use in the report.  

The test time is 10 minutes and its average value is taken  

a. Use IEC 62087:200x video content_DVD_50 through IEC 62087:200x video content_ HD_ DVD_60 for signal sources as required by IEC 62087.1:2008  The signal is tested.  

(7) standby power consumption test (should be less than 1 watt)  

(8) Specification, color box and spec have relevant index test mentioned.  

Note: If the indicators mentioned in the specification, color box and SPEC cannot be confirmed or tested on site, Remark or information shall be made in the report.  

Metrics that have not been tested cannot be written as confirmed or tested  

5) Confirmatory test (one set)  

(1) Check the packing method (see whether the attachment will be out of place after transportation)  

(2) Check the content of the manual (check every word and every sentence)  

(3) Color box,SPEC or BOM content check  

(4) The default color temperature is determined  

(5) Confirmation of plugs and power cords in relevant countries  

(6) Frequency range test of TV, DTV and Radio (probe, tail, and information below indicate that only the minimum and maximum frequencies of these two points in each frequency band are measured in practice)  

(7) AFC function confirmation  

(8) HDCP protocol screen test  

(9) V-CHIP classification determination  

(10) Confirm the manufacturer and model of the display screen  

(11) Screen size measurement  

(12) Screen resolution confirmation  

(13) Screen view confirmation  

(14) Sleep automatic switch setting and confirmation  

(15) Reset test (whether the changed language, brightness and other Settings can be restored to factory Settings)  

(16) Confirmation of the national television format used  

(17) Check the functions of the remote control  

(18) Approval mark required by the country and the product shall be used for confirmation  

(19) Wall mount installation test (smoothness and firmness, pay attention to whether there are fewer screws or other accessories)  

(20) HDMI CEC function test  

(21) In WiFi, test whether it can be correctly connected under different encryption modes  

(22) CRT magnetic field test (set to the selling country standard)  

(23) Drop Test (1 corner, 3 sides, 6 sides) -- You need to check with the factory to see if this test is allowed before dropping. You should use a special drop device to test  

After the drop test, internal inspection should pay attention to:  

The heavier components on the power supply board are prone to plate cracks around them  

Fixed pillar crack on display  

(24) Running test:  

Timer/clock Check to set the current accurate time  

The voltage is set to the rated voltage, and the audio and video are played continuously for 4 hours  

At the same time, PRV video test can be conducted  

(25) Internal check (Number of samples: one)  

display Panel, Main IC, Speaker, Tuner/transformer marking, Plug  

Carefully disassemble the sample housing to ensure that the original position/state of the internal structure, components and internal wires of the product are not affected.  

I do good inspection:  

a. Carefully disassemble the sample housing to ensure that the original position/state of the internal structure, components and internal wires of the product will not be affected.  

b. Check the internal wires and electrical connections. From the time the power cord enters the product, twist/pull/toggle the wires or connection terminals with your fingers if necessary to check the connection status.  

c. The conductor should not be damaged, clipped or scalded  

d. Wires shall be properly protected to ensure that they do not come into contact with burrs, edges, heating/moving parts, etc. that may impair their insulation performance.  The metal holes through which the insulated wires pass shall have smooth sufficiently rounded surfaces or be fitted with bushings  

e. Wires shall be connected, supported, clamped or secured in such a manner as to prevent stress or loosening of wires and joints  

a. Check that the color of the internal cables of the power cable meets the requirements  

b. Check the grounding cable (if any) connections and symbols  

c. Move the moving part and check that it does not touch other parts  

d. The exposed wire shall be rigidly fixed  

e. Check the internal structure of the product and its process against the sample (if any). The structure of the product should be consistent with the sample. The plastic parts should not be damaged, melted, deformed, etc. The metal parts should not be rusted, damaged, etc  

f. Check screws and connections,  

g. When removing the screw, check whether the screw can be fully fixed. It should not be twisted tightly or loosened.  

h. Check that the disassembled screws are not cracked or whitened  

i. Screws or nuts used for electrical connections or ground connections must be securely secured to prevent loosening