By: Brian Johnson, AB6UI 20 Sept 2017 DIY Software Defined Radio Receiver By: Brian Johnson, AB6UI 20 Sept 2017

Welcome to the world of SDR! With a few inexpensive parts and free software you can enter the exciting world of Software Defined Radio. SDR is similar to regular radio but with a twist. Instead of using expensive ham radio gear you are using a Raspberry Pi (computer) and an inexpensive USB RTL SDR dongle & Upconverter. This system allows you to listen to 0 to 1675MHz AM FM: both narrow band and wideband. Upper/Lower Sideband (USB/LSB). CW: Continuous Wave for Morse code enthusiasts. You can also receive and demodulate digital modes such as AX25 (PACKET), ADS-B (aircraft positions), AIS (ship positions), AP25 and TETRA (digital trunk radio) and many others.

What you need to get started Raspberry Pi 3B The NooElec-SDR USB Dongle The NooElec-Upconverter GQRX software 7” LCD Display (any HDMI display will work)

Raspberry Pi 3B Based on the latest Broadcom 2837 ARMv8 64 bit processor the Raspberry Pi 3 Model B is faster and more powerful than its predecessors. Technical Specifications: Broadcom BCM2837 64bit ARMv8 QUAD Core 64bit Processor powered Single Board Computer running at 1.2GHz - 1GB RAM BCM43143 WiFi on board Bluetooth Low Energy (BLE) on board - 40pin extended GPIO - 4 x USB2 ports Full size HDMI - and Composite video port 4 pole Stereo output

The SDR Dongle Details: These units are based on the R820T2-Based Software Defined Radio made by NooElec. They have a frequency capability of approximately 25MHz-1700MHz. There is also an RTL2832U IC on board of course, which acts as the demodulator and USB interface. The connector type is SMA on the SDR. There are plenty of adapter and adapter cables available and you will need one in order to connect up to your antenna.

NooElec Upconverter This MF/HF converter for software defined radio will allow you to listen to MF and HF through your existing software defined radio (SDR). The latest model v1.3 include increased sensitivity, ultra-low voltage noise floor, optional battery-powered operation, side-mounted LED indicators, fully-assembled broadband RF noise-source circuit, u.fl socket for optional external clock injection, surface-mount high-accuracy oscillator and much, much more! It has female SMA input and output jacks, ESD protection on the input to product your Ham It Up and SDR, ultra-high-Q & low ESR components used for all filters, PTC protection fuse on power input, enable/disable passthrough toggle switch, and open-hardware design with full published circuitry and specifications.

GQRX GQRX is a simple, intuitive, small and fast R-Pi based DSP application for Software Defined Radio. Gqrx is an open source software defined radio receiver (SDR) powered by the GNU Radio and the Qt graphical toolkit.

LANDZO 7 Inch Touch Screen Details: 800*480 HD resolution 7 inches capacitive touch area Supports backlight control Supports raspberry pi with drivers under Raspbian system

Putting it all together A short video clip of it all in action

Other misc hardware you may need: 5V 3A Wall wart The completed project needs a heavy duty (3A-5V) power supply to run Micro SD Card The R-Pi includes a slot for a micro SD card but you need at least an 8GB card to load the OS Case for the LCD Screen Headphones or amplified speaker

Backup NooElec