DIPOL Weekly Review – TV and SAT TV, CCTV, WLAN

Distortion-free stretchable meta-displays.

The Korean Institute of Machinery and Materials (KIMM) has successfully developed the world's first stretchable meta-display technology that can be stretched to 25% of its original size without image distortion. KIMM's Nano-Mechanics Department has been researching micro-LED technology since 2008. The result has been achieved by using technology to design and manufacture metamaterials with unique mechanical properties not found in nature. Most stretchable materials, such as rubber, exhibit shrinkage in width when stretched longitudinally, resulting in a change in aspect ratio. This was also the case with flexible displays. The image became distorted.

Dr. Bongkyun Jang stated that his team has solved the fundamental problem of image distortion in stretchable displays. He and his team will now aim to commercialize the meta-display technology so that it can be applied to various electronic products in the near future. The newly developed stretchable meta-display technology is expected to contribute to platform differentiation for mobile electronic devices such as cell phones and tablets.

How to receive DVB-T2/HEVC signal in a SMATV system with DVB-T/MPEG-4 receivers?

By the end of 2022, a new standard of terrestrial television broadcasting, called DVB-T2/HEVC, will be introduced throughout the European Union. The introduction of the new broadcasting standard should not require changing the receiving antenna, but one may need to change its direction or upgrade the TV system , if the TV sets do not support DVB-T2 standard with HEVC codec (also known as H.265 or MPEG-H part 2) and process audio encoded according to the E-AC-3 standard (also known as Dolby Digital Plus or DD+). While in the case of a small system with one or several TVs there should be no problem (it is enough to buy a DVB-T2/HEVC decoder that is connected via HDMI output), it may be quite an issue for larger number of TVs, especially in boarding houses, hotels and the like. The pictures below show the measurement of the DVB-T2 signal with the use of ST-5150 Signal R10842 meter and example system with the change of the DVB-T2/HEVC standard to DVB-T/H264 possible.

Multimode fiber and 10 Gbps transmission.

Transmission at 10 Gbps is now becoming a standard in office areas, multi-family buildings and even home use. This speed is required not only in the backbone of the network, but also in the direct connection of end stations.

When deciding to use multimode fibers, remember that the ranges for 10 Gbps are limited. The most popular fiber standard MM om2 enables transmission at a speed of 10 Gbps over a maximum distance of 82 m, i.e. less than copper twisted pair category 6A certified for that speed (100 m according to the 10GBASE-T standard). This is can be really tricky to network designers or contractors who do not pay attention to the fiber standard in the cable used.

Higher multimode fiber standards, i.e. OM3 and OM4, allow 10 Gbit/s transmission over distances of respectively: 300 m and 500 m. The choice is much safer in this matter. The affordable OM3 is a good choice also from the perspective of local network development, because it offers connections with speeds of 40 Gbitps and 100 Gbitps at a distance of 100 m.

Saving photos from cameras in the series I Hikvision IP recorders.

Series I Hikvision IP recorders, e.g. DS-7608NI-I2 K22083 have the ability to take snapshots of camera images according to a schedule or triggered by an alarm event. For time triggering, it is possible to set the time interval in the range from 3 seconds to 24 hours. For event triggering, you can set the time and frequency for taking post-event snapshots. The photos will be taken using the second stream. This solution can be used, for example, to create a history of a construction progress. When scheduled to record continuously on all days, snapshots will be taken at the specified interval for 24 hours a day. It is possible to define up to 8 time intervals for each day of the week and define the method of taking snapshots (continuous, motion detection, event, etc.) for each interval.

Tester for network cabling.

The FS8117 N70511 tester is used to measure: cable continuity, cable length, attenuation of individual pairs, PoE voltages, and distance to cable fault location. It allows to detect connection faults in UTP/STP, telephone and coaxial cables. Additionally, the FS8117 tester is equipped with advanced cable pair locator. It is based on a unique technique that combines the generation of both analog and digital tones , allowing for significantly increased accuracy in locating cable bundles. High sensitivity allows searching for cables even under plaster up to the depth of 100 cm. The "Find Port" function for fast localization of a port in a network device found only in advanced network testers.

One of the most useful functions of the tester is searching for devices in the network. Once the network addressing is properly set, the tester searches for all active devices. This function is useful when addressing a new device. After checking, the installer can test if a particular IP address is not used in the network. Another useful function is to check the speed of the connection (10/100/1000 Mbps) between the meter and, for example, a switch to test the correct installation of the cable or connectors.

LTE network signal amplification. The Signal GDW-505 A6777 repeater is used to amplify EGSM, GSM, DCS, WCDMA, and LTE signals and bring them indoors. The device is ideal for places where the signal is so weak that making calls or transmitting data via cellular phone is impossible. An example may be a place located far from the transmitter or a building with thick walls, cellars (coffee shops) or modern windows with panes of covered with metallic compounds... >>>more