Overview: The talk recounts an experiment in using fruit and vegetable to power practical transceivers. It discusses how much electric energy various fruits and vegetables can generate and how to build QRPp radios.
About the speaker: Born in Hiroshima, Hiroki Kato was first licensed as JA4AAO when he was in high school there. He came to the US in 1966 to pursue graduate studies. Dr. Kato taught political science and linguistics at the Univ of Hawaii, Northwestern and Harvard. He came to Silicon Valley in the 1990s to work for early startups. He enjoys QRP portable ops, casual HF DX and digital modes. He collects and restores boat anchor radios, including WWII-era radios. His book The Paraset Radio: the Story of a WWII Spy-Radio and How to Build a Replica was recently published by the RSGB. His two sons attended Stanford and one of his grandsons is currently a freshman at Stanford.
I will give a brief overview of the microwave spectrum and who's using it, then will describe radar sensor MMIC technology and how we repurposed it as a ham radio transceiver. Next, the radio system budget (SNR = system gain - path loss) and how better antennas lead to greater range. Finally, a discussion of the contributors to path loss and how path (and weather) selection led to a new distance record for this band. Along the way, we'll learn about several radios based on the radar MMICs, including the very popular VK3CV design (about 500 units shipped to hams world wide) and the 122 GHz beacon at the W6YX site.
About the Speaker
Mike Lavelle (K6ML) started out on HF and 2m as WN2ZHL in high school, and then studied microwave semiconductor design in college. As a co-op student at COMSAT Labs he built 7 and 14 GHz propagation beacons for early communications satellites. At some point, he was mesmerized by the new 8 bit microprocessors and switched to designing computer display terminals in Silicon Valley, eventually becoming a 3-D graphics hardware architect at Sun Microsystems and later pushing some more pixels around at Silicon Image. Now that he's retired, he's reverted to tinkering with ham radio, HF thru mm waves.
Patrick van Eijk Director of LoRa Business Development at Semtech
What do you get when you utilize blockchain Decentralized Finance (DeFi) and cryptocurrency to build one of the fastest-growing wireless networks? How would you build a global IoT wireless network in a matter of years, not decades, and at a fraction of the cost of traditional mobile carriers who might spend billions to buy spectrum, build cell towers, and gain subscribers?
The answer is the Decentralized Wireless (DeWi) movement which is growing at breakneck speeds. At the center of this movement is the Helium blockchain, which is powered by the LoRaWAN wireless protocol that has seen tremendous growth in IoT applications. The Helium DeWi model has amassed legions of crypto mining fans, and its “hotspot miners” have been deployed worldwide.
We’ll explore the benefits of a DeWi network and the multitude of Helium IoT applications used in small business to big city projects.