FeatherHAB: 2-gram High Altitude Balloon Tracker using Si4464 EZRadioPRO
An excellent and clever solution using a SoC ISM radio as 2m APRS transceiver: FeatherHAB: 2-gram High Altitude Balloon Tracker
Author: Zoltan
Receiving WSPR With An RTL-SDR V3 Dongle
The V3 version RTL-SDR blog dongle is perfectly fits for WSPR reception as per my tests. As it has internal switches it uses only one SMA connector for HF (500kHz to 24 MHz) and UHF operation, no need for changing connectors for direct sampling mode. This makes the RTL-SDR V3 dongle really convenient and easy Read more about Receiving WSPR With An RTL-SDR V3 Dongle[…]
RPi Speaker – An Open Source Fully Integrated Active Speaker for RPi
Didn’t find an elegant compact solutions out there. I’m using only the GPIO pins, no need to route the audio jack output back to the PCB like existing solutions. Also using an on board amplifier which supplied from RPi 5V. Built a few prototypes yet and working nice 🙂 Enjoy! https://github.com/rfsparkling/RPi_Speaker https://www.reddit.com/r/RASPBERRY_PI_PROJECTS/comments/55hk5k/rpi_speaker_an_open_source_fully_integrated/
Remote Spectrum Monitoring Drone from RTL-SDR, RPi, 4G internet using OpenWebRX
Remote Spectrum Monitoring Drone from RTL-SDR, RPi, 4G internet using OpenWebRX Can be used as an improvised “virtual antenna tower” for example in emergency situations, ham radio activities or experimenting. Possibly words cheapest aerial spectrum monitoring tool as of today. You can see APRS and ham radio FM repeaters in the spectrum plot of the Read more about Remote Spectrum Monitoring Drone from RTL-SDR, RPi, 4G internet using OpenWebRX[…]
The ZL1SIX Ocean Floater
“An ocean going marine buoy containing a GPS and QRP-Labs Ultimate3S based transmitter. This project is intended to drift in the Pacific Ocean at the mercy of the tides, currents and wind directions while sending its position, battery voltage and temperature information via HF radio telemetry in WSPR and JT9 modes.” Source: http://www.qsl.net/zl1rs/oceanfloater1.html
TINY RASPBERRY PI SHIELD FOR HIGH-QUALITY RF SIGNALS
http://hackaday.com/2016/03/16/tiny-raspberry-pi-shield-for-high-quality-rf-signals/
FastDDC and GPGPU: progress toward a full HF web receiver for everyone
Check my friend, András Retzler’s new blog about cutting edge SDR technology at: blog.sdr.hu
KIWISDR: 30 MHZ BANDWIDTH SDR FOR VLF/LF/MF/HF with OpenWebRX
It uses a LTC 14-bit 65 MHz ADC and Xilinx Artix-7 A35 FPGA, and also has an integrated SDR based GPS receiver which is used to automatically compensate for any frequency drift from the main 66.6 MHz oscillator. The features of the KiwiSDR include: 100% Open Source / Open Hardware. Includes VLF-HF active antenna and associated power injector PCBs. Read more about KIWISDR: 30 MHZ BANDWIDTH SDR FOR VLF/LF/MF/HF with OpenWebRX[…]
Optimal impedance matching of RTL SDR in direct sampling with 16:1 BALUN
Here is an excellent article about that: http://www.g8jnj.net/softwaredefinedradio.htm Here is where I’ve found it: http://www.rtl-sdr.com/measuring-the-input-impedance-of-the-rtl2832u-direct-sampling-input-pins/