John WB2OSZ

by Jon Adams, N7UV LoRa's Got a Lot of Knobs LoRa is a digital mode with technical characteristics that are extremely well documented publicly. To wit, one of the many things many people experimenting with LoRa find are the incredible link margins that LoRa can support. At 433

By Jon Adams, N7UV LoRa is a digital mode with technical characteristics that are well documented publicly. LoRa has extremely good performance in noisy environments, and can successfully transfer data at SNRs well below the noise floor. Here's a snap from the second-generation Semtech SX1261/2 data sheet

By Jon Adams, N7UV Semtech (Camarillo, CA, USA) has made upwards of a half-billion LoRa chips to date, and those chips find their way into much of the Internet of Things. LoRa is a pretty amazing technology, and it carries with it some things that the ham needs to know

by Jon Adams, N7UV You've heard of the FM capture effect, where an FM receiver will favor one station over the other so long as there's just enough receive signal strength difference between the two transmitters. If you're old enough to remember listening to

By Jon Adams N7UV A really great thing about sub-GHz LoRa is that there are 9 different bandwidths and 8 different spreading factors from which to choose, each set giving a link unique characteristics.  A really challenging thing about LoRa is that there are 9 different bandwidth and 8 different

By Jon Adams N7UV Did you know that a LoRa receiver, in addition to doing all the cool LoRa stuff, natively provides received signal strength indication (RSSI) and received signal to noise ratio (SNR)? And signal frequency offset in hertz? For every packet?  For a few US$ product, it'

By Jon Adams N7UV LoRa transceivers are typical all-on-a-chip RF transceivers, just like those SDR sticks, and to a much lesser extent Bluetooth and Wi-Fi. Their front ends are wide, have high dynamic range, and 99% of the signal filtering is done in software. If you've ever used

by Oguz TA4OHN Ask ten operators how a beacon from a handheld ends up as a moving dot on a website and you will get ten half-answers. Everyone knows the endpoints - a radio on one side, a map on the other - but the middle is a fog of

by fangzhou.xu BG5ESN We all know that although APRS provides a global short‑message network, its rate limitations and broadcast constraints prevent it from becoming a true innovation platform for worldwide amateur radio digital infrastructure. For this reason, I propose a brand‑new high‑speed global data exchange network

New APRS devices and applications are being developed at a furious pace. There have been hundreds of new device/application identifiers requested at aprs-deviceid . These developers would like to you know what they have been up to. Radio Messenger A full-featured messaging app for iPhone, iPad and Mac, with built-in