SDR

I did some antenna measurement with RTL-DSR with help of directional coupler. Before I realised I had directional coupler, I did some experimenting with antenna signal splitter. RF splitters are widely used in RF applications. The enable RF power to be split or combined within an environment where the characteristic impedance is maintained. There are →

Software-defined radio (SDR) is a radio communication system where components that have been traditionally implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system. Experimenting with software defined radio used to be expensive, but now it is cheap. Nowadays it is →

This is good stuff! Building your own SDR-based Passive Radar on a Shoestring http://hackaday.com/2015/06/05/building-your-own-sdr-based-passive-radar-on-a-shoestring/ two $8 RTL software defined radio dongles and two log-periodic antennas. And get this, the radar system you’re going to build works by listening for existing transmissions that bounce off the targets being measured! A passive radar is a special type →

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 →

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 →

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 →

http://www.rtl-sdr.com/cheating-at-pokemon-go-with-a-hackrf-and-gps-spoofing/ GPS spoofing used to need expensive special equipment available to big players ony, but not anymore… →

  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 →

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 →