No. 41/2014 (Dec. 15, 2014)
Double-speed wireless networks?
A team of engineers from the University of Texas has developed a semiconductor circuit that allows for radio communication in full duplex mode in the same channel. This means that the radio channel can be simultaneously used for both transmission and reception. It eliminates one of the fundamental problems associated with wireless transmission, that the transmission and reception of data cannot take place simultaneously in the same band, and the transmitting and receiving networks have to operate alternately, with sequential access to the transmission channel. So, a practical implementation of this solution would mean twice more efficient use of the radio spectrum.The developed device is a circulator, i.e. a circuit transferring signals only between respective ports. The idea of the circulator is to transmit the signal from the first port only to the second, from the second only the third, and so on. Such solution isolates the transmitted and received signals. The system uses parametric modulation of three symmetrically coupled resonators. Their resonant frequencies are modulated by external signals having the same amplitude, but different phases (shifted by 120 degrees). All this makes the difference between the transmitted and received signals so large, that the receiver can operate properly, without undue interference from the transmitter.

View of the circulator
(source: www.extremetech.com)
(source: www.extremetech.com)
Of course, in the case of mobile devices there are concerns about the increase in energy consumption and the accompanying temperature rise caused by continuous operation of the transmitter. However, these issues seem to be resolvable by using adequate hardware and software means. It's a high-stakes game, so the originators will surely sort these questions out.
Although a television system failure does not belong to the most critical ones from the point of view of human life or health, it may be connected with significant inconvenience. Periodic power failures can significantly increase the cost of maintenance of the system, and breaks in the service can cause dissatisfaction of the users. To keep the highest standards in this field, DIPOL has introduced high quality power supply dedicated for TERRA systems - UP413 (12V/4.5A) R82533.
The UP413 R82533 power supply is dedicated for use in TERRA antenna systems with amplifiers, receivers, analog and digital TV modulators, IPTV streamers. After installing two R82533 units, a failure of one of them will not affect in any way the operation of the system - the second one will automatically and immediately take over its function.
Lighting control in F&Home Radio system.
F&Home RADIO is a wireless intelligent building system dedicated for apartments, houses and business premises. Its concept and capabilities allow for the implementation of functions that so far seemed to be impossible, or available only to organizations and rich people. F&Home is a cheap solution, and its modular design allows for the division of the entire investment into stages spread over time.Below there is an example of lighting project capable of the following functions:
- switching on and off each lamp circuit using a mobile app or switch on the wall,
- switching on and off both lamp circuits using a mobile app,
- lighting level adjustment in each lamp circuit using a mobile app,
- lighting level adjustment in both lamp circuits using a mobile app.
The control of lighting can be carried out by the application installed on a smartphone, through a web browser or using wall switches.
View the touch screen of a mobile device along with the illustration of the operation of the control circuits
The project uses two rH-D1S2 F1302 modules for connecting two lamp circuits.
The construction of a mechanical splice.
Mechanical splices ULTIMODE FAST-MS1 L5550 are used for permanent connections of optical fibers without the need of employing fusion splicers. Everything the installer has to do before application of the splice is to remove the protective layers (jacket and aramid fibers), strip the buffer, clean the core cladding and cleave the fiber with the two active layers.Mechanical splice ULTIMODE FAST-MS1 L5550
The prepared ends of the fibers to be spliced should then be inserted to the both sides of the L5550 mechanical splice. The body of the splice contains V-groove device with holes slightly larger than the fibers. These holes are filled with optical gel compensating for cutting imperfections and imprecise positioning. After full insertion of the fibers, they have to be locked with the buckles. The versatile design of the mechanical splice allows for splicing optical fibers with buffer coating diameters of 0.25 mm (using the included reducer) and 0.9 mm.
Wireless remote controller RE-2K.
The RE-2K G5812 wireless two-channel controller is used for control of electrical devices with relay inputs, via wireless key fobs. The remote controller can work with up to 16 remote key fobs G5902 (433 MHz remote key fobs from SATEL). The board of the controller is equipped with two relays, programming button and pins (2x3), two-color LED indicator (of operation mode and programming actions).
View of the RE-2K board
Depending on how the jumpers are set on the pins, the relays can operate in different modes:
- bistable (no jumper) - by pressing the key of a fob the user switches the relay status to the opposite
- pulse (jumper set on the two lower pins) - the relay is switched ON as long as the user presses the key of a fob (the fob operation time is limited to 30 seconds)
- monostable (jumper set on the two upper pins) - by pressing the key of a fob the user switches the relay status to ON (for 5 seconds by default or for a programmed period, from 1 to 250 seconds)
The procedure of adding a key fob is quite simple:
- press the programming button – the LED starts blinking green
- press any button on the remote key fob – the LED starts blinking red
- press the remote key fob button again, the LED light changes to steady green -the remote key fob has been entered into the memory
Removal of a remote key fob from the system is possible only by deleting all the registered key fobs from the memory. To do so, the installer should press and hold down the programming button for approx. 7 seconds – the LED will start blinking red, thus indicating that the memory is being cleared (and the factory setting of monostable mode is being restored). When the LED steadily lights green again, the controller is ready for adding the remote key fobs.
Aside from applications in intruder alarm systems, the controller can be used e.g. for the control of a barrier or gate. With two independent channels, it can be can also be used, e.g. for turning on the light on a driveway, disarming the alarm system, or just to switch on an espresso machine :).
Video outputs in Hikvision DVRs.
Digital video recorders are usually equipped with several video outputs, either to match various monitors or connect additional ones. There are three popular types of video outputs, HDMI, VGA and BNC. In Hikvision DVRs the menus can be displayed on monitor(s) connected to different outputs, depending on the model and firmware version.The configuration of video settings for displaying the DVR menu is possible only locally (with the physical access to the DVR). Usually the HDMI and VGA outputs are configured as synchronous (they provide the video simultaneously, and the image can be displayed on any or both of them, provided that the monitors are connected before switching on the DVR). Otherwise, the menu is available via BNC output (if exists). The DVR outputs can also be configured as asynchronous, which means that the menu appears on one output depending on the priority, according to the rule HDMI> VGA> BNC.
Mounting Plate for 19" RACK Cabinets (4U, with DIN-TH35-24xS rail) R82539 is designed for mounting devices compliant with DIN standard in the rear part of a 19" RACK cabinet. The connection of the DIN rail with the plate ensures mechanical stability of the mounted equipment, plus the possibility of attaching the power and signal cables to the mounting plate. The mounting plate is an economical alternative to the DIN rail rack mounting bracket R82538. | ||
Combo HD Receiver: Ferguson Ariva 153 COMBO (DVB-S/S2+DVB-T/T2/C) A99386 belongs to the combo group, capable of receiving SD/HD channels from satellites (digital DVB-S and DVB-S2 formats), digital terrestrial TV SD/HD broadcasts (DVB-T/T2), and cable TV (DVB-C). The satellite broadcasts are received by one tuner, and the rest by the second. Thanks to built-in USB port it also supports Time-shift and PVR-ready function - recording of selected broadcasts on external data storage devices, such as flash or hard drives. Support for MP3, OGG, FLAC, JPEG, MPEG, and MKV formats makes the universal receiver a home entertainment center. Ariva 153 Combo also supports selected web services (Youtube, Youporn, Dailimotion, Google Maps and others). | ||
Worth reading
How to dim the bulb without getting out of bed? The most frequent use of Exta free modules is remote lighting control. In the diagram below, the RDP-01 F5301 wireless dimmer is controlled by the F5112 2-channel remote control. The set allows for switching on/off and dimming/brightening the main light source in the room. Such functionality is particularly useful for the elderly or disabled people, who find it difficult to move around the room.
Remote control of lighting with exta free system.
The unwell person can switch on/off and dim the lighting in the room.
The unwell person can switch on/off and dim the lighting in the room.