Radio Tower

LimeSDR Mini Initial Thoughts and Setup Guide

I’ve been using the $22 RTL-SDR dongle for the last few years to learn about software defined radio (SDR.) I decided it was time to graduate to the next level of SDR functionality, which for me includes the ability to transmit, a wider bandwidth and a higher frequency range. There is a huge gap between the RTL-SDR and the next most sophisticated SDR in both … Continue reading LimeSDR Mini Initial Thoughts and Setup Guide

Update: RisingHF Gateway RHF0M301 with Loriot Community Network

It’s been about a year since I posted an unofficial manual for getting the Seeed Studio 915 MHz RisingHF Raspberry Pi gateway up and running with Loriot. In that time, I had hoped that there would be more resources available for enthusiasts to find information about setting up gateways, nodes and sensors. However, it looks like complete and reliable information is still hard to come … Continue reading Update: RisingHF Gateway RHF0M301 with Loriot Community Network

HD Radio waveform

Listening to HD Radio with an SDR

“HD Radio” is the technology by which US radio stations broadcast digital audio along with their regular analog signal. Standard FM radios only receive the analog signal and ignore the digital data. You need an HD Radio to listen to the digital audio. HD radios are most popular as features in newer automobiles, but adoption outside of car radios, as well as awareness by the … Continue reading Listening to HD Radio with an SDR

Seeed Studio LoRa Kit

Getting Started with LoRa

LoRa is a radio technology for long range, low bit rate communication among sensors (temperature, light, location etc…) and other IOT devices. The sensors send their data to a radio receiver known as a gateway. The leading protocol used by sensors and gateways to manage communications, frequency, data rate and security is known as LoRaWAN. The gateway transfers the sensor data to the cloud so … Continue reading Getting Started with LoRa

SDR dongle

Sniffing GSM with SDR

I’ve been fascinated by software defined radio (SDR) for years but investigating the GSM cellular network has always been just a little too challenging and slightly out of reach. All of that changed earlier this year when someone finally posted a workable, step-by-step guide for decoding (but not decrypting) cellular (GSM) radio traffic. For those not familiar, SDR involves moving much of the functionality of … Continue reading Sniffing GSM with SDR

Pushing a bt.tn button

The Internet Button

While perusing the various channels on IFTTT recently, I came across one for something called “bt.tn.” My curiosity led me to a Finnish site that sells a very interesting product: a large pushbutton that can control anything that is connected to the internet. The bt.tn comes in various colors and has both Wi-Fi and cellular models. The operation from a user’s perspective could not be simpler. You … Continue reading The Internet Button

Sharing Data From the Netduino

As mentioned in an earlier post, I’ve been working with the Netduino microprocessor board, a .NET version of the open source Arduino. In preparation for designing a home energy monitoring system, I created a small project to measure and post data from the Netduino. The simplest circuit I could find consisted of a photocell and a resistor wired into one of the analog inputs. Every … Continue reading Sharing Data From the Netduino