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

New translucent solar cell technology – double-sided tandem solar cells.

Researchers at the Korea Institute for Energy Research (KIER) have made significant progress in the stability and performance of translucent solar cells. They have developed perovskite (calcium-titanium oxide) based translucent solar cells with a record efficiency (energy conversion efficiency) of 21.68%, making them the world's most efficient among perovskite solar cells using transparent electrodes. In addition, the cells exhibited remarkable durability, with more than 99% of initial efficiency maintained after 240 hours of operation. As the world seeks to gradually become less dependent on fossil fuels to meet its energy needs, high-efficiency solar cells are needed. Conventional solar cells have an energy conversion efficiency of only 20%, which means that we cannot use the remaining 80% of the percentage falling on existing photovoltaic infrastructure. To improve the energy conversion rate, researchers are working with materials such as perovskites that can provide high energy efficiency.

Auxiliary monitor function in Sunell NVRs.

Sunell NVRs are equipped with two video outputs: HDMI and VGA which, by default, present the same image (parallel outputs). Models with 8 channels or more offer an auxiliary monitor function, which allows partially independent display of camera images. The number of channels that can be displayed on each screen is limited to half the standard number of channels. For example, on an eight-channel NVR, a maximum of four channels can be previewed on each screen.

The main menu is always displayed on the monitor connected via HDMI cable, while the auxiliary monitor can only present a preview image.

TV system in a multi-family building.

Multiswitch systems responsible for supplying DVB-T2 digital terrestrial TV and DVB-S/S2 satellite TV signals to apartments are an excellent complement, as well as an alternative to cable network systems in multi-family residential buildings. It is the end-user who decides what programs to watch by purchasing the appropriate satellite receiver or by signing an individual contract with one of the digital platform providers. TERRA products, dedicated to use SMATV systems, are primarily top-class equipment covered by a four-year warranty. TV systems based on those components guarantee great signal reception for long.

Connection of additional reader via RS-485 to IP Villa Hikvision door station.

Hikvision Villa IP door stations of the DS-KV8xx3-WME1(B) series have an RS-485 input that can be used to connect an additional reader. The reader can be mounted on the exit side of the property in case the customer does not want to open the gate with a handle or local opening button. The DS-K1107AM G75369 can be used as an exit reader. Before connecting the reader, set the appropriate address on it, (e.g.:1) by moving the first DIP switch to the ON position. Then connect the reader via RS-485 z-bus to the door station (yellow wire RS-485(+), blue wire (RS-485(-)). After connecting the reader, power the door station using PoE switch or 12 V/DC voltage and the reader using 12 V/DC voltage. After the video door entry system is properly configured and a Mifare (13.56 MHz) key fob is added, applying it to the reader built into the door station or connected via RS-485 will drive relay one at the door station and release the electric strike.

Building a house – what cabling for the Internet?

Given the progressive development of technology, changes in the offerings of service providers, as well as technical innovations appearing on the market, the recommended method of building cabling is very different from that of a few years ago.

Facing the task of designing Internet cabling, while planning the installation, you have to take into account several factors that may influence the final layout of the cables. Laying too few cables or choosing wrong type of cable can cause significant limitations in the future. On the other hand, it is important to consider the economic factor and not to plan too many cables that will never be used. So how do you currently wire your home correctly?

Choice of cabling. The basic transmission medium used for building LANs should be copper twisted-pair cable. The use of fiber optics for transmission in the home will certainly not make sense in the next several years. In homes, it is recommended to use twisted-pair cables of 5e or 6 category. This type of cable allows to transmit data at speeds up to 1 Gbps, which will certainly prove sufficient over the next dozen or so years or even decades. Those with a larger budget can consider laying a category 6 twisted-pair cable, which allows to transmit data even up to 10 Gbps. Given the availability of devices working at a speed of 2.5 Gbps, such a twisted pair may prove to be a safer solution. Another issue is the choice between shielded and unshielded twisted pair. It may seem that a more expensive, shielded cable will always be a better solution, note however that the use of shielded cable imposes the use of shielded system components: wall sockets (the necessity of grounding) and active devices (shielded ports). Taking into account the price, availability and difficult installation of shielded cables and devices, and the fact that in a residential building the electromagnetic interference is not significant, it is recommended to lay unshielded twisted pair cable.

Green line ⇒ E1171 50 Ohm Tri-Lan 240 coaxial cable for LTE/5G antenna
Purple line ⇒ E1611 NETSET U/UTP 6 gel-filled, black – outdoor twisted pair cable for WLAN antenna
Blue line ⇒ E1608 NETSET U/UTP 6 cable – indoor twisted pair cable for outlets
Light blue line ⇒ Internet Service Provider cable

Topology – how arrange? It seems optimal to lead one cable to each room in the house. It will give you the freedom to choose the location of the access point or to connect two access points without any problems when the range of one device is not sufficient. Note that the WiFi signal must reach devices such as air conditioners, heat pumps (central heating furnaces), recuperators, refrigerators and other devices equipped with WiFi modules. The ability to freely connect a computer or other device to a wired network may also prove important. Keep in mind that some applications may require cable connection for stable operation. This applies, for example, to streaming high-definition video or playing online games. When planning cabling, one should remember that the Internet is used today not only by personal computers. Twisted-pair cables have to be led to the places where TV sets, consoles and home theaters are installed. It is also worth thinking about one socket in the kitchen, bathroom or any other room.

Where to get the signal from? When building LAN network in a house you should consider potential sources of Internet access. Routing twisted-pair cable to the lowest building level enables easy connection of services from the local ISP providing traditional service, or – after installing a cable modem – from the cable network. One outdoor UTP/FTP cable leading to the roof will allow to access the Internet via radio (access point integrated with antenna). It is also worth to think about the wireless LTE/5G network that is gaining popularity. Two 50 Ohm coaxial cables going to the roof will allow you to mount external antennas using MIMO technology and use the full potential of high-speed Internet.

What kind of knife for mechanical splices?

Mechanical splices for connecting optical fibers are still a popular solution used by installers who occasionally perform installations based on fiber optic cabling. A common question that arises when first shopping for mechanical splicing accessories is that of choosing a fiber cutter.

The fiber cutter, regardless of the version, is the most expensive part of the kit, so it is worth paying a little more attention to it. There are 2 types of knives to choose from:

The L5882 cutter is used when welding fibers with a fiber optic splicer. It guarantees very good quality and repeatability of cutting. Despite this, the use of this type of knife for mechanical splicing does not seem to be a good idea. In a situation where the guillotine is used with a welding machine, the installer gets feedback that the knife is cutting badly as a result of the blade becoming unsettled or blunted. It is also possible that the blade does not cut at all. It is then necessary to properly adjust the blade. However, this is not possible without having a splicer and verifying the effects of adjusting the setting on the splicer's screen. Therefore, using the L5882 knife for mechanical welding runs the risk of unknowingly making poor cuts that can have a real impact on the quality of the splice.

In contrast, the L5801 knife does not require any adjustment. Its initial cut quality is inferior to that of the L5882, but acceptable when performing mechanical splicing. The cuts are not so repeatable, some of them could be rejected by a thermal splicer, but in the vast majority of cases the quality of the cut is quite sufficient to perform a mechanical splice.

Causes of problems with starting optical RF/SAT systems. Fiber optic cables are increasingly used in SMATV terrestrial and satellite systems. Since this type of cabling is still a novelty for many installers, who have been making such systems based on traditional copper cabling for years, they relatively often have problems in getting them up and running. These problems are usually easy to diagnose and eliminate...>>>more