I’ve finally gotten around to assembling a breakout board for the Skyworks SKY65116 UHF amplifier. It’s really amazing how the state of the art in RF ICs has advanced. They can still be on the expensive side ($6 at digikey), but still relatively cheap when you consider the cost of all the support parts that it takes to build an amplifier from a RF transistor. This particular amplifier has a 50 ohm input and output, and 35dB of gain. It works from 390Mhz to 500Mhz, which means its perfect for the 70cm ham band. The breakout board is stupid simple, copied directly from the evaluation board schematic in the datasheet, but I’ll include schematic and design files anyway.
SKY65116 Amplifier - [Link]
PCB layout is tough. Laying out a PCB isn’t in itself too hard once you learn how the tools work, but high-speed (10MHz+) introduces a virtual mine field of potential issues that you may not be aware of until it’s too late. While experience is the best teacher, Analog Devices has a great application note explaining some of the key pitfalls to avoid when dealing with high speed designs (which is basically anything today): A Practical Guide to High-Speed Printed-Circuit-Board Layout. Some of it is a bit heady, but not more than it needs to be, and it really does lay out a lot of key information that you may not have been aware of. Want to improve your PCB design skills? Print this out, and keep reading through it until it starts to make sense. There’s years of bench time worth of information in there.
EEBookshelf: High Speed PCB Layout - [Link]
RF networking is getting huge these days. With new RF nodes being developed on what seems like a monthly schedule. This means new and established companies are getting in the game. I’m pretty sure that everybody knows of Digi international (manufacturers of Xbee RF nodes) and regard them to be the current King of RF networking, BUT with ninja-like progress companies like Synapse Wireless have snuck up on them and started offering superior products. Syanpse nodes have the ability to wirelessly program Arduino UNOs at distances of >250ft without hardware mods or painful configuration processes. The nodes are both a network module and user-programmable microcontroller in one and on top of that they have to ability to do self-healing mesh networking. Their specs seem to outdo xbees on many levels, which begs the question, Synapse Wireless where have you been all my life???
There’s a New SheRifF in Town and Their Name is Synapse Wireless - [Link]
A lot of times we need to keep track of data from a device or a sensor located in a remote location from the point where it is processed. In other situations we desire wireless solutions for ease. Using long cables, infrared (IR) or other means are often tedious and not loss-less. Imagine collecting pH level data from a chemically lethal or toxic treatment plant where human presence is highly health hazardous. Running long cables from the pH sensor to the control or monitor station will surely introduce noisy signals and signal-to-noise ratio will thus drastically decrease. The result is erroneous data acquisition and thereby false decisions may be generated. If infrared signals or other optical means including lasers are used, they will need good obstacle-free line of sight or expensive and delicate optical fibers. Thus the solution stays in the radio frequency (RF) domain. This article talks about interfacing low cost RF modules (KST-TX01 and KST-RX806) for transmitting data between two remotely located PIC microcontrollers.
Wireless data transmission between two microcontrollers using KST-TX01 and KST-RX806 rf modules - [Link]
The RC1180-KNX2 from Radiocrafts AS targets building automation applications and claims to be the world’s first RF module with a complete embedded KNX-RF multiprotocol stack. KNX-RF Multi is an extension of the European standard for building automation with extra redundancy and increased reliability. The embedded protocol is backward compatible with KNX-RF 1.1 and KNX Ready and can be used with unidirectional and bidirectional devices.
The new module is intended to be used with sensors, actuators and other home and building automation devices. It operates in the 868 MHz band using Listen Before Talk (LBT) and frequency agility to reduce collisions. Up to five frequencies are scanned and selected automatically. A single receiver can be linked with up to 64 transmitters, enabling very large RF networks. [via]
RF module features embedded multiprotocol stack - [Link]
Inspired by the finding that over 60% of oscilloscope users also use a spectrum analyzer to troubleshoot embedded system designs with integrated wireless functionality, Tektronix has developed the world’s first mixed domain oscilloscope (MDO), which provides the functionality of an oscilloscope and a spectrum analyzer in a single instrument. The new MDO4000 Mixed Domain Oscilloscope series gives engineers the unique ability to capture time-correlated analogue, digital and RF signals for a complete system view. [via]
Scope / spectrum analyzer combo captures time-correlated analogue, digital and RF signals - [Link]
Semiconductor manufacturer NXP is mighty proud of its new high-power transistor, called BLF578XR, which is good for 1.2 kilowatts of RF power output. The device is suitable for use in RF amplifiers operating within the in the 10 to 500 MHz frequency range and has proved it’s up against extremely adverse operating conditions. [via]
The first indestructible transistor? - [Link]
For sure, right now you’re surrounded by electromagnetic energy transmitted from sources such as radio and television transmitters, mobile phone networks and satellite communications systems. Researchers from the Georgia Institute of Technology have created a device that is able to scavenge this ambient energy so it can be used to power small electronic devices such as networks of wireless sensors, microprocessors and communications chips.
Manos Tentzeris, a professor in the Georgia Tech School of Electrical and Computer Engineering, and his team used inkjet printing technology to combine sensors, antennas and energy scavenging capabilities on paper or flexible polymers. Presently, the team’s scavenging technology can take advantage of frequencies from FM radio to radar, a range of 100 MHz to 15 GHz or higher. The devices capture this energy, convert it from AC to DC, and then store it in capacitors and batteries.
Capture free energy 24/7 - [Link]
Deepak from Mindfront.net acquired a PIR alarm sensor module which transmitted a digital code over 433 MHz RF to signal an alarm receiver. The problem: he didn’t have the factory receiver. So he set out to sniff the transmitted RF signal using a RCR-433-AS receiver module with the data out fed into an oscilloscope. This allowed him to monitor the digital coded signal pattern and decode it into individual bits.
Hacking a PIR RF signal with PIC 12F683 – [Link]