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

Invisible 3D labels for object identification.

When downloading digital music files from the web, you can get additional information embedded in them, such as the song name, genre, artist or producer. The same is true for downloading photos, which can include information about the time, date, or location of where the photo was taken. These solutions led a PhD student in the Department of Electronics and Computer Science at MIT, Mustafa Doga Dogan, to wonder if engineers could create a similar solution for physical objects. The idea was a bit abstract at first, but after the advent of an infrared-enabled smartphone in 2020, it became more feasible. The ability of infrared to see through some materials impenetrable to visible light proved to be a particularly useful feature.

The concept invented by Dogan was named by him as "InfraredTags". Instead of the standard barcodes placed on products, which can be removed, detached or otherwise become unreadable over time, the invisible discrete tags are placed inside objects made with a standard 3D printer. Last year, Dogan spent several months trying to find a suitable variety of plastic through which infrared light could penetrate. After an extensive search, he came across a custom plastic filament produced by a small German company. He then used a spectrophotometer at MIT's materials science lab to examine the sample. He discovered that it was opaque to visible light, but transparent or translucent to infrared light. The next step was to experiment with creating tags on the printer.

One option was to produce the code by cutting tiny air gaps in the plastic layer to replace the zeros and ones. Another one, assuming that the available printer could handle it, was to use two types of plastic, the first that allows visible light through, and the second on which the opaque code is written. The latter proved to be a better solution because it could provide more contrast and, at the same time, could be easier to read with infrared cameras. The tags themselves can consist of familiar bar codes that present information in a linear, one-dimensional format. Two-dimensional options, such as square QR codes and so-called ArUco tags, can potentially hold more information in the same area. The MIT team has developed a software "user interface" that specifies exactly how the tag should look and where it should appear in a given object. Multiple tags can be placed in the same object, which will actually make it easier to access information when views are obstructed from certain angles. Dogan and his colleagues have created several prototypes, including cups with barcodes engraved inside the container walls under a one-millimeter plastic shell that can be read by IR cameras. They also created a prototype Wi-Fi router with invisible tags that reveal the network name or password depending on the perspective from which it is viewed. They made a cheap circular video game controller that is completely passive, with no electronic components. There is only a barcode (ArUco tag) inside. The player simply spins the wheel right or left, and an inexpensive ($20) infrared camera can determine the player's orientation in space. So the possibilities for using this concept seem very broad.

Hotel mode in Signal T2-MINI receivers.

The hotel mode is a function practically unheard of in DVB-T2 receivers that allows you to block the possibility of changing any parameters in the receiver's menu. When enabled, the user can only view the channel list, change the program, change the soundtrack and adjust the volume. All other functions remain locked and require a predefined password to change. In the hotel mode, the receiver starts with channel 1 (from software version DIPOL_V5.2.1.28). It can be used for broadcasting advertising program of the hotel on this channel. The hotel mode is extremely useful in hotels, hospitals and other facilities where the receiver can be used by many people.

The Signal T2-MINI A99313 receiver can be mounted on the back of the TV set using two mounting pads E950230/E950231 and cable clamps E952054. The pads can also be used for neat arrangement of the cabling. The receiver installed this way remains 9 mm away from the TV set which ensures good ventilation. The total installation height does not exceed 25 mm which makes it possible to easily hang the TV on a wall using any LCD bracket without the risk of damaging the wall or the receiver itself.

Direct burial fiber optic cable.

DAC, i.e. Direct Access Cables can be buried in the ground without the use of additional protective conduits, although they are exposed to external factors: freezing and thawing of the ground, movements caused by cyclical vibrations of e.g. vehicles, infiltration of rain water into the ground, etc. DAC cables have sheaths made of high density polyethylene (HDPE). It makes them rigid and highly resistant to mechanical damage (crush resistance - 4000 N). Two FRP rods of 0.9 mm in diameter additionally protect the cable against breaking. These cables have so called Water Block (WB) design which blocks the internal flow of water along the cable.

The DAC cables offered by DIPOL***, despite their robust design, are easy to prepare for splicing, the only thing needed is the Ideal L5922 stripper for safe opening of the central tube. A pair of pliers is sufficient to cut the outer sheath and a pair of combination pliers to tear along the FRP rods.

Read more about this and other fiber optic cable types in our Fiber optic cables guide.

Calculation of the archiving time and bandwidth required.

Storage and Network Calculatoris Hikvision brand software that allows you to select the appropriate hard disk capacity for the recorder depending on the required archiving time. It also calculates the required bandwidth for the selected number of cameras. Supported resolutions range from CIF (352 x 288 pix) to 12 MPix (4000 x 3000 pix), and the following compression methods are supported: H.265+, H.265, H.264+, H.264.

The software is very user-friendly and intuitive. First, select the "PAL" or "NTSC" color system. Then, in the "Channel Number" field, specify the number of cameras that will be added to the recorder along with such parameters as encoding, resolution, fps, and the degree of scene composition. After selecting the encoding parameters, the calculator will automatically set a suggested bitrate. After adding the cameras, the three tabs are available: "Space Given", "Time Given" and "Bandwidth". In the “Space Given” tab, after entering the capacity of the hard drives and selecting the backup time per day, the information will be given for how many days the recordings will be stored. In the “Time Given” tab, you can enter the number of days for which the recordings are to be stored in order to receive information on the required disk capacity. In the Bandwidth tab, information on the band generated by the selected cameras is provided.

Diagram of an IP video intercom system for a single-family house with three floors.

A diagram of the Hikvision IP video intercom system for a single-family house is shown below. The system is based on the one-subscriber IP Villa DS-KV8113-WME1(B) G73639 door station with a built-in 2 MP camera and two relays for control of the gate and wicket. DS-KH6320-WTE1 G74001 monitors equipped with Wi-Fi interface are installed on three floors and configured in extension mode. This means that when the call button on the door station is pressed, all monitors will ring at the same time. When a call is answered at any of the monitors, the others will be disconnected. The Ultipower N299851 switch with 4 PoE ports supporting 802.3af/at is used to supply the door/gate station and monitors. The system is connected to the Internet via the Mercusys AC12G N2933 router. The wicket is controlled with the use of the Bira S12U G74220 electric door strike with steel keeper/latch with 4 mm adjustment range, suitable for 12 V AC or DC power supply. It is supplied with the 12 V DC M1820 power supply.

More accurate crimping of RJ-45 plugs.

DIPOL now offers EZ RJ-45 (cat. 5e J2012_100 and 6 J2013_100) plugs. Their hallmark is a loopthrough on individual wires that allows for a faster and more efficient termination. The plug should be crimped and the excess conductor cut off with the dedicated E7911 crimping tool.

The plug has an elastic latch that prevents it from sliding out of the socket. Individual contacts have sharp, slightly spaced prongs, sticking directly into the insulation of individual wires, ensuring a reliable and durable connection.

Introducing Unicable/dSCR signal to a standard multiswitch system. Currently, there are lots of satellite receiver models available on the market. Almost all of them support the SCR/Unicable system compliant with EN50494 and/or EN50607 using single-cable technology. The greatest advantage of this solution is the possibility to build branched systems, as in the case of terrestrial television. No star topology is required here. This means that the terrestrial television system can be easily adapted to the reception and distribution of satellite signals (taking into account the limitation of the number of users connected to one multiswitch)... >>>more