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

Miniaturization of IR detectors will increase the capabilities of consumer electronics.

The extreme miniaturization of infrared (IR) detectors is crucial for their integration into next-generation consumer electronics, wearable devices and very small satellites. Until now, IR detectors have relied on bulky and expensive materials and technologies. As reported in the scientific journal Nature Photonics, a team led by Dr. Ivan Shorubalko, a researcher at Empa Institute, has succeeded in developing a cost-effective way to miniaturize IR spectrometers based on a quantum dot photodetector that can be integrated into a single chip. The researchers have built a miniature waveguide spectrometer that uses a subwavelength photodetector as a light detector.

As shown in the figure below, the photodetector consists of a gold electrode located at the bottom, which acts as a scattering center, a photoactive layer consisting of colloidal mercury telluride – HgTe – quantum dots, and a top electrode made of gold. Moving the mirror, the measured photocurrent reproduces the intensity of standing wave light, or infrared light. The Fourier transform of the measured signal gives the optical spectrum.

Miniaturization of infrared spectrometers will lead to their wider use in consumer electronics, such as smartphones that allow food inspection, detection of hazardous chemicals, monitoring of air pollution, etc. Detecting some chemicals without lab equipment may become possible. Furthermore, devices containing such detectors can be used to detect counterfeit drugs, as well as greenhouse gases such as methane or CO₂.

TERRA SMATV multiswitch system.

Systems based on multiswitches are professional and the most popular way to deliver terrestrial TV (FM/DAB and DVB-T2) and satellite SAT (DVB-S/S2) signals to more subscribers. 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.

In one of Krakow's housing estates the multiswitch system has been installed based on TERRA equipment.

ColorVu Hikvision pan-tilt cameras.

Dipol offers two pan-tilt cameras: the ceiling-mounted DS-2CD2387G2P-LSU/SL K01569, and the compact DS-2CD2T87G2P-LSU/SL K03937, which combine two key technologies ColorVu and AcuSense. With ColorVu technology, the camera can capture color images round the clock while retaining important identification details. The AcuSense technology increases the effectiveness of the surveillance system by eliminating false and nuisance alarms through human/vehicle object filtering.

The cameras are equipped with two 1/1.8" sensors which allow for a total image resolution of 8 MP. They have two ultra-bright lenses with an aperture of F1.0 and a focal length of 4 mm allowing for 180° observation of the scene. Built-in speaker and microphone allow for audio recording, audio alerts and audio communication. In extreme conditions, a white light illuminator can automatically turn on and illuminate the scene to provide good quality color images. In addition, the cameras can issue a light alarm to scare away intruders. Support for the legacy and latest H.265(+) compression methods allows for the archiving time of recordings to be extended while maintaining excellent image quality and backward compatibility. Additional functions to help improve image quality including: AGC, 3D-DNR, WDR (130 dB), BLC, HLC and built-in image analytics (VCA based on a deep learning algorithm, allows you to use the camera for advanced projects. The camera can be powered conventionally with 12 VDC or through PoE (compliant with the 802.802.3af standard).

How do HDMI to IP converters work?

HDMI converters use multicast transmission to transfer data between the transmitter and receiver. For this reason, it is not recommended to use converters in home networks (such a stream is sent in a traditional/straight network to each device thus overloading switches as well as routers). It is best to create a dedicated network for the converters, or dedicated VLANs (virtual local area networks).

HDbitT protocol is used for transmission. High-Definition Digital Bit Transmission Technology enables the transmission of audio/video at resolutions up to 4Kx2K @ 60Hz over the network cables, electrical wiring, fiber optic cable, coaxial cables, or wirelessly.

HDbitT ensures all-in-one connectivity, enabling 4K Ultra HD audio and video distribution, as well as the transmission of RS232, IR, and USB control signals.

Key benefits of HDbiT:

• the distance over which a signal can be transmitted can far exceed 100 m,
• HDbitT supports features such as: CEC, EDID and HDCP,
• support for multiple transmission media such as twisted pair, coaxial cable, fiber optics, electrical network, wireless network,
• possibility to secure transmission with the AES protocol,
• using the existing computer network for signal transmission,
• using efficient compression to save bandwidth in the network,
• plug and play devices,
• support for point-to-point and point-to-multipoint connections.

Devices supporting the HDbitT protocol:

• H3606 H3606 HDMI to IP Converter + remote control extender,
• H3606R HDMI to IP converter + remote control extender-receiver,
• H3613 HDMI to IP converter with USB extender,
• H3613R HDMI to IP converter with USB extender-receiver,
• H3614 HDMI to IP Signal (multicast) converter v4.0,
• H3614R HDMI to IP Signal converter (multicast) – v4.0 receiver.

Splicing optical fibers – testing with VFL.

Signal Fire Ai-9 splicers have a built-in visual VFL fault locator. This device generates visible (red) light with a wavelength of 650 nm for preliminary check of a splice. After removing a pigtail from the package, the user connects its plug to the VFL socket, while the free end of the fiber is spliced with that of the cable. After splicing, it is possible to generate visible light with the "650" button on the front of the splicer. The person at the other end of the link checks if the light reaches the other end of the optical path.

Interestingly, Signal Fire splicer can splice when the visible light is already propagated through the fiber. Splicing with the VFL on relies on the splicer mechanical system and its software. Some splicers refuse to work if this is the case. This feature can be useful when visible light is introduced into several or more fibers using an optical splitter on one side of the connection (using a dedicated VFL, to avoid switching the light source and being constantly in touch with the splicing person), and splicing is performed on the other side.

LTE interference signal in DVB-T2 system. The 700 MHz band is no longer used for terrestrial TV signals. This band has been made available to mobile network operators for 5G/LTE services. Therefore, the TV channels with the highest frequencies (channels above 40) are the most at risk of interference from LTE transmitters. The image on the TV screen may freeze, colored stripes and squares (picture frameup) may appear. How can such a diagnosis be confirmed? The best way is to hire an installer who is equipped with a professional meter...>>>more