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Wire electrical test project is recommended
1. The characteristic impedance
Assuming an infinite uniform cable stretching, under a certain frequency impedance on the emission end is called "characteristic impedance.Generally speaking, the characteristic impedance is composed of impedance sections and reactance, it is a useful signal in the frequency domain function, has nothing to do with the length, with Ω said.Side, the high frequency asymptote of characteristic impedance for a fixed value, namely the resistance.For example, 50 or 75 ohm coaxial line will be;In the above 1 MHZ twisted-pair phone line and Internet communication line is going to be 100 ohms.When high frequency (> 100 kHz) general use time domain reflectometer test.

2. The attenuation
Attenuation is the signal strength through a wire or cable or connector after the loss of value.It is an insulator (medium) the influence of material and structure, also refers to the output power or voltage ratio, incident power or voltage reduce how much, and in the form of the dB said.General use network analyzer test.
3. The crosstalk
Using the tester, network analyzer (NA) or FLUKE DSP4300 tester.
The far end crosstalk (FEXT) :
Far end crosstalk is to point to in the same cable bundle of other twisted pair work in the remote transmitter, cause for this twisted pair of interference caused by the other end of the receiver in the same direction.The far end crosstalk after loop attenuation is smooth, so the impact of small.(in db).
Near end crosstalk (NEXT) :
Near end crosstalk is occurred in the same side, is in the same cable bundle of other twisted-pair transmitter to work in the cause for this twisted pair to a receiver located on the same side in the opposite direction.The near end crosstalk attenuation was smooth without loop, so its impact is much bigger than far end crosstalk.(in db).
Transfer delay is 4.
Transmission delay is under fixed frequency signal through the time needed for fixed length of transmission line.In nanoseconds (ns).Use tester: time domain reflectometry (TDR).
5. Poor propagation delay
Transmission delay differential refers to two or more transmission lines of the propagation delay of the gap between the maximum or minimum value.In nanoseconds (ns).
Use tester: time domain reflectometry (TDR).
6. Return loss
When the transmission point line impedance is changed, it was seen as discrete points, which will lead to the incoming voltage or current wave reflection, the incident energy and thus suffer, is also in the form of the dB said.It refers to the ratio of incident power and reflection power, reaction is coaxial line characteristic impedance and the theory of impedance matching.
Using the tester, network analyzer (NA) or FLUKE try DSP4300 tester
7. Rise time (bandwidth)
It is a sign of difference, is to have a load of difference line to the output measurement.Rise time of the critical value has been measured, when sending half a clock character, 100% and 0% of state usually is classified as 1 s and 0 s.
Use tester: time domain reflectometry (TDR)

HDMI 1.4 related content

1.4 wire what new feature?
HDMI Ethernet channel
The organiser audio channel
HDMI function of 3 d
Support 4 k x 2 k resolution
Support for the expansion of the color space
The micro HDMI connector (D)
Automotive connection system (E)

(1) the HDMI Ethernet channel
HDMI specification 1.4 increased data path in the cable, to achieve two-way transfer of a high speed. With the function of the equipment after the link will be available at a speed of 100 MB/SEC Ethernet line to send and receive data, and make the equipment immediately IP based devices. HDMI Ethernet channel allows HDMI equipment integrated Internet function, without using other Ethernet cable, can be Shared with other HDMI equipment its Internet connection.This new capability as well as share content between HDMI equipment required for the interconnection of architecture
(2) audio back channel
Adds an audio channel in the latest specification, can reduce the processing and number of wires required when upload the audio playback.High-definition TV in directly receive audio and video content, this new audio back channels, can let high-definition TV does not need to add other cable, direct use of HDMI cable to transmit audio stream to the A/V receiver.
(3) the HDMI 3 d function
Specification version 1.4 for HDMI equipment defines the common 3 d format and resolution, this specification will use 3 d system input/output part of the standardization, the resolution of the specification to a maximum of dual channel 1080 p.
(4) support 4 k x 2 k resolution
The latest specification for HDMI device can support four times the 1080 p resolution HD resolution.New specifications to support 4 k x 2 k resolution, has caused many digital cinema HDMI interface to use the content of the same standard resolution adopted by the transmission.Supported formats including:
3840x2160 24Hz/25Hz/30Hz
4096x2160 24Hz
(5) support for the expansion of the color space
HDMI technology can now support color space designed for digital cameras.The display device with a HDMI function can support sYCC601, Adobe RGB and AdobeYCC601 after connecting to the digital camera can show more realistic color right.
(6) the micro HDMI connector
Micro HDMI connector is very small size 19 feet connector, can support the resolution of the portable devices up to 1080 p.In this new type of joint were 50% smaller than the current HDMI mini connector.
(7) vehicle connection system
Automotive wiring system is designed for the car hd content transmission the wiring designed specification.HDMI 1.4 specifications the designed solution, can handle the car wiring faces various problems such as high temperature, vibration, noise and environmental factors.Automotive connection system is the auto makers in the design of the car hd content transmission when a very effective solution.

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