SDR

Software defined radio

Antenna measurements with RF noise source

Using the wide band characteristics of SDR radios, it is possible replicate some of the functionality of much more expensive equipment such as a vector network analyzer.  Actually what SDR can do it scalar network analyzer functionality. A scalar network analyzer can measure amplitude, but a vector network analyzer can measure amplitude and phase and

Filter measurements with RF noise source

I got my BG7TBL RF noise source to make some RF measurements. To make those measurements, I needed some instructions how to make them. I first started with filter measurements because I could make them with the devices I have. Two good tutorials for doing measurement are Measuring Filters and VSWR With RTL-SDR and RTL-SDR

BG7TBL RF noise source

I have played with software defined radio using cheap DVB-T stick for some time. Receiving radio transmissions is interesting, but it works also for other applications. By reading RTL-SDR Tutorial: Measuring filter characteristics and antenna VSWR with an RTL-SDR and noise source article I understood that I could use my RTL-SDR stick for many RF

RTL-SDR receives Bluetooth LE

  Sniffing and Decoding NRF24L01+ and Bluetooth LE Packets For Under $30 article points to an interesting hack: able to decode NRF24L01+ and Bluetooth Low Energy protocols using RTL-SDR (=a cheap USB digital TV tuner based digital radio). So cheap practicality anyone can obtain the equipment quickly. Some special hacking was needed because there are

GSM is insecure

Whatever assurances have been given about the security of GSM cellphone calls, forget about them now. Breaking GSM With a $15 Phone … Plus Smarts article tells that a pair of researchers demonstrated a start-to-finish means of eavesdropping on encrypted GSM cellphone calls and text messages, using only four sub-$15 telephones as network “sniffers,” a