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

Will the warmth of the human body power cellular phones?

A team of scientists from South Korea under the leadership of professor of electrical engineering Byung Jin Cho from Korea Advanced Institute of Science and Technology (KAIST) has developed a completely new type of thermocouples producing electricity from the heat of the human body. The item is extremely lightweight and flexible - the permissible bending radius of thermocouple sets is only 20 mm. The thermoelectric materials are printed on a glass fabric. The research shows that the new solution is 14 times more effective than the currently used ceramic solutions. The test strip has a length of about 10 cm.

So far, scientists have used thermocouples based on organic or inorganic materials. Organic thermocouples consist of very flexible polymers that are ideally suited for the production of electricity from the heat of the human body. Their disadvantage is, however, very low output power. Thermoelectric generators based on inorganic materials are capable of producing much higher electrical power, but their downside is much greater weight and rigidity. In the new solution, both the upper and lower substrate is the glass fabric. Korean scientists say that a wrist strap with an area of ​​10x10 cm will be able to produce electricity with a power of 40 mW at a temperature difference of 17°C between the human skin and the environment.

The modern world is dependent on electricity, since all areas of life and economy require this form of energy. Today, about 90 percent of the electricity produced in the world comes from the heat. So far, almost all known methods of electrical energy production are not very effective, especially those regarded as "environmentally friendly".

The presented method of creating flexible, light and efficient thermoelectric generators can also be, according to the originators, the beginning of the real use of thermal energy normally wasted as heat by vehicles, aircraft, vessels, industrial installations. But now there is another challenge - to commercialize the technology and make it as efficient as possible.

Optical receivers in TV antenna systems.

Optical receivers convert optical signals into an electrical form. The electrical signals are provided to the subscriber's devices (forward path), and in the case of using return path (IP services) other signals are transmitted in the opposite direction.

Optical receivers (nodes) cooperate with optical transmitters sending modulated light over single-mode optical fibers. Such optical links can transmit multiple satellite and terrestrial DVB-T/DAB channels from the headend or master antenna even to distant locations, using PON technology (Passive Optical Network).

Due to small size, modern design and suitable parameters, TERRA OD-003 R81728 is the ideal subscriber receiver for FTTH systems

The table below lists the available TERRA optical receivers:

Due to high maximum output level (above 105 dBμV), optical receivers OD-120 R81724, OD-002 R81726 and OD-010R62 R817272 can be used at larger distances between them and subscribers' outlets and/or can distribute the signals to a greater number of outlets. The OD-010R62 R817272 model has return channel (5-65 MHz).

Thanks to small size, modern design and suitable parameters, the OD-003 R81728 and OD-004R81730OD-003 receivers are ideal for subscribers in FTTH systems. The maximum RF output level of 80 dBµV is suitable for distribution of RF channels via passive components throughout an apartment, office or one-family house. The OD-004 R81730 model with output band up to 2400 MHz can also distribute DVB-S/S2 channels.

PoE - two versions.

PoE (Power over Ethernet) is the name of a number of methods that allow for powering network devices through UTP/FTP cables. This way it is possible to power devices such as cameras, phones, switches, access points, etc. In 2003, the IEEE established 802.3af PoE standard, upgraded to 802.3at in 2009. 802.3at distinguishes between the first type (prior 802.3af) and the second type with maximum transmitted power of 30 W, nearly two times higher. The second type is suitable to power cameras with high-power IR illuminators, IP telephones, small network printers etc.

Comparison of the two types of PoE:

PoE switches supporting IEEE 802.3at type 2:

Video monitoring of a gas/petrol station with a store.

To minimize cases of theft at his station, the owner has decided to install an IP CCTV system. The company which was given the task of installing the system, decided to use Sunell cameras. The video surveillance system covers the whole area of the station. The entrance, pumps, and exit are monitored by K1685 cameras. The cameras, equipped with IR illuminators with Super Flux LEDs operating within 30 m range and with mechanical IR filters, provide excellent visibility both during day and night. With the resolution of 2 megapixels they allow for good recognition of people (appearance, facial features) and vehicles (make, color and license plate number). The mere sight of cameras deters potential offenders - the number of thefts dropped 10 times. In the case of such an event, the archived recording of the incident is given to the police.

The architecture of the IP CCTV system at the gas/petrol station.
The main components are: Sunell cameras K1685, K1695,
Ultipower PoE switch N29986, and PC running NUUO software

Inside the store there are surveillance cameras K1695 that observe checkout counters to prevent possible misunderstandings during transactions. The material from the cameras is archived on a server running NUUO K3116 software, which allows continuous recording, or recording triggered by motion detection, as well as counting people shopping in the store. Such statistics allow for a more efficient distribution of goods on the shelves and for maximizing profits.

NAS server as the network video recorder.

Thecus N2310 NAS server N3901 with 2 bays for SATA 3.5" HDDs (each up to 4 TB) is dedicated for home and SOHO applications. The device provides Web-based file access and allows streaming of data stored on the HDD(s) to mobile devices based on Android and iOS.

The device supports SAMBA and FTP protocols, which allows to use it as NVR server in IP CCTV systems.

Below there is a diagram of IP CCTV system recording the video streams from the IP cameras on the N3901 NAS server. The archived recordings can be viewed on any device compatible with DLNA (e.g. a television). It is the most economical network storage solution allowing for simultaneous video recording, data archiving, disk space sharing etc.

A simple IP CCTV system using the N3901 NAS server

A range of 3- and 5-meter patch cords available in stock.

There are several standards of optical fibers and over 50 types of optical connectors. It often happens that a patch cord must be installed immediately, but a supplier needs some time to execute the order.

DIPOL offers over 50 different patch cords with a wide range of terminations. In addition to the most popular patch cords with a length of 1.5 m, the offer includes 3- and 5-meter items with the most popular fibers and connectors. Patch cords are often used in server rooms, in distribution frames, portable systems, offices, factories, laboratories. Thanks to special designs, the patch cords can be connected and disconnected many times without a risk of damaging the fibers.

April 17, 2014 - WIZFON-4 - a new Partner of DIPOL in Szczecin, Poland. We welcome all customers from Western Pomerania to our new store in Szczecin, 29 Powtancow Wielkopolski Avenue. WIZFON-4 is a company with over 20 years of tradition and numerous business contacts, in a good location. Currently, DIPOL has 10 branches in Poland, and sales offices in 7 European countries.

Changing the location of the server room. After the construction of a new building, the owner of a production plant decided to move the telecommunications facility. The previous location (production hall) did not provide a sufficient level of safety and environmental conditions required for the servers... more

Optical link between the old and new building ensures LAN connection and access to the Internet,
as well as transmission of images from 8 analog cameras