Multi-band antenna 2J301 offers several properties for which it´s worth to consider its usage in your devices.
Decent gain, good VSWR values, small dimensions, resistance to outdoor conditions and a simple mount method are probably basic features, which we´d expect from external antennas for the GSM/UMTS, PCS bands. Antenna 2J301M/SMA from company 2J provides all this but it features yet another positive feature – a good price.
That´s why, if you´re searching for an antenna with good specification for a good price, 2J301M is a good choice. An elegant design from an ABS plastic is suitable for virtually every application and an easy installation is ensured by a magnetic bottom plate together with a 2.5 m long flexible cable (RG174) with the SMA connector.
High-quality GSM/3G signal directly to your device – [Link]
Researchers at Rice University (USA) have developed a micron-scale spatial light modulator (SLM) similar to those currently used in sensing and imaging devices, but with the potential to run several orders of magnitude faster. Their ‘antenna on a chip’ operates in 3D ‘free space’ instead of the two-dimensional space of conventional semiconductor devices.
A device that looks like a tiny washboard may clean the clocks of current commercial products used to manipulate infrared light.
New research by the Rice University lab of Qianfan Xu has produced a micron-scale spatial light modulator (SLM) like those used in sensing and imaging devices, but with the potential to run orders of magnitude faster. Unlike other devices in two-dimensional semiconducting chips, the Rice chips work in three-dimensional “free space.”
In current optical computing devices, light is confined to two-dimensional circuitry and travels in waveguides from point to point. According to the researchers, 2D systems ignore the massive multiplexing capability of optical systems arising from the fact that multiple light beams can propagate in the same space without affecting each other. [via]
“Antenna on Chip” Manipulates Light at Warp Speed - [Link]
Using a better antenna to improve DCF77 reception on long distances
We are in the prototyping phase of building a Nixie clock using 1N-14 Nixie tubes. The clock is designed around a PIC16F886 MCU, 74141N BCD decoder/driver and CNY74 optocouplers using common circuit topology. High DC voltage (+ 180VDC ) is generated using MAX1771 step-up switching regulator, which is quite efficient (if you use appropriate components).
Our clock will have some nice features:
- Compact design
- Manual time configuration
- DCF77 time synchronization
- Sync success indicator
- HV shutdown during sync (to reduce noise received by DCF module)
- Super-capacitor time backup
- Thermal protection
- ICSP connector etc.
When clock is complete we will release it as open source-hardware here at Electronics-Lab.com
We decided to use DCF77 signal as time reference for two main reasons, it’s quite easy to receive it and it’s very accurate for the reason that carrier signal is generated from atomic clocks.
But, what about receiving and decoding DCF77 signal? Read the rest of this entry »
RFID antennas are traditionally produced by etching, but a new process developed by Walki, a manufacturer of technical laminates, aims to displace etching by laser cutting. The process uses paper as the substrate and eliminates the need for liquid chemicals, making process residue easily recyclable. Laser cutting also accelerates the design to production cycle and allows extremely precise fabrication of circuit board patterns. The finished antenna, consisting of just paper and aluminium, is fully recyclable.
The new technology is dubbed Walki-4E where 4E stands for efficient, exact, ecological and economical and is based on a laminate of aluminium on a paper substrate, with the aluminium foil cut in patterns using a laser. It can be used to produce any type of flexible circuit, ranging from RFID antennas to radiators and flexible displays. The first product to be launched using this technology is Walki-Pantenna, a UHF RFID antenna. [via]
Laser cutting makes antennas greener - [Link]
ESA has provided research and development guidance to Finnish company Patria, with the help of Tampere University of Technology, in designing a search and rescue radio antenna that can be sewn into a life vest.
Made from highly flexible, lightweight material that is robust against water exposure and moist conditions, and resistant to wear and tear, this special antenna has been designed for use by the Cospas-Sarsat worldwide search and rescue satellite system. Cospas-Sarsat has been operating for almost 30 years and has helped to rescue more than 26,000 victims in distress. [via]
Washable wearable antenna - [Link]
Clever! – [via]
A big issue in setting up satellite communications networks is the antennas – it takes time to set them up. In the wake of a big disaster cell networks can be damaged when the towers fall and take months to repair. For television crews and military units carrying a rigid satellite antenna can be a serious logistical problem, as even a metre-sized dish is quite heavy and difficult to transport.
Enter GATR Technologies, which has designed an inflatable 1.2-metre satellite antenna that can fit into a backpack and be carried by a single person. The company’s antenna looks something like a beach ball. It is a double-layered sphere with one layer a nylon mesh and the other made from sail material. The antenna is in the centre.
Inflatable antenna you can stick in your backpack - [Link]
An introduction to AM/FM active antennas: [via]
This article is a reference design (RD) for an automobile AM/FM active antenna. The RD presents the flexibility of the MAX2180 active antenna low-noise amplifier (LNA) and shows how to set the AM and FM gain and the automatic gain control attack point. Single and dual antenna schematics are detailed, including the input and output matching circuits. Using this design together with the data sheet and device’s evaluation (EV) kit, a prototype antenna can easily be developed for a wide range of active antenna requirements.
App note: AM/FM active antenna - [Link]
How to Make a Human Antenna @ Discovery News…
In the setup, a participant wore a backpack containing a laptop and a data acquisition device connected through a wire to a conductive pad on the back of the participant’s neck. The pad measured the voltages picked up by participants, who performed specific gestures around light switches. Software in the laptop generated positioning instructions and at each switch, the gesture order was randomized to eliminate bias.
The experiments showed that electromagnetic noise is so predictable that it can be used it to figure out where a person is standing, what the person is doing, and even where a hand is placed on a wall. The team used a simple sensor that was essentially just a piece of metal, but Morris said that ultimately a sensor could be placed in the user’s hand or anywhere else that the radio signals being picked up by the body can be gathered.
“Our bodies, it turns out, are actually really good and relatively colorful antennas,” Morris said. The team presented their results earlier this week in Vancouver at the ACM CHI Conference on Human Factors in Computing Systems.
The researchers learned that in a typical house, the electromagnetic noise changes noticeably from room to room because of the various appliances in them. Then they applied artificial intelligence to the data.
“The noise is different enough in those different environments that the computer can actually use machine learning to tell the difference,” Morris said.
How to Make a Human Antenna - [Link]
This simple a 7 element Yagi is ideal for portable operation. The elements can be removed and replaced in a few minutes. The 2.42 Metre boom will fit inside a car. All of the elements are made from 6mm solid aluminum rod. The boom is made from 50x25mm (2×1 in) timber. The driven element is a half wavelength dipole.
Portable Yagi for 144MHz - [Link]