Projets radio

Raspberry Pi for HAM Radio

Publicités

Introduction

Since 2012, the Raspberry Pi nano computer has become an increasingly important part of the DIY and « maker » community. The increase in power of the Raspberry Pi over the years offers very interesting possibilities for radio amateurs. Indeed, it allows not to permanently monopolize a PC in the decoding of frames with software like WSJT-X, FLDIGI, etc…, without forgetting the possibility to control the Raspberry Pi remotely and thus to be able to work outside the radio shack as I can sometimes do on my couch. Moreover, this nano computer is now widely used in any Hotspot (DMR or D-STAR).

So why in a club, so few OM use this tool?

I have often asked myself this question and I think it comes from the use of the operating system (OS). When you power on a Raspberry PI, the OS, called Raspbian is stored on a microSD card. This is a Linux distribution specially designed for the Raspberry.

When you want to install a software under Linux, you no longer have to double-click on a downloaded file like « setup.exe » like under Windows. Indeed, you often have to use the console and thus type « command lines » to install or configure a program. This can seem off-putting and frankly very tedious. We are so used to using a graphical environment that we feel like we are back to the early 80’s micro-computing.

However, the mastery of some basic commands in linux console allows to consider the installation of different programs and hardware such as:

The tutorial  is specially designed for beginners wishing to acquire the basics in the installation of the Raspberry Pi through the use of radio software :

The full tutorial is available here (9 pdf files)

Update : add part 9 (14/10/2020)

Raspbian operating system with graphic interface (Desktop).

Raspbian Lite operating system without GUI (Command Line).

Basic commands, file access rights and WSPR.

Installing and using openWebRX

The goal of openWebRX is to install in its radio shack, a software to create its own web SDR. When you are on the move, you just need to connect to your laptop at home to listen to the desired frequency band using your own antennas.

Installation and use of the r2could project

The NOAA (National Oceanic and Atmospheric Administration) satellites have been in orbit for a long time. They emit continuous weather images on 137Mhz. Currently there are 3 (NOAA15,18 and 19), they have been joined by a Russian satellite Meteor-M2 which broadcasts color images.

The advantage of using a Raspberry Pi to receive weather images is obvious, we have no regrets about leaving it on 24 hours a day. Its software automatically updates the orbital parameters of the satellites (TLE: « Two-Line Elements ») and manages the reception and decoding of the images. Moreover, r2could also decodes the telemetry of cubesats. As soon as a new cubesat is in service, the update is automatic.

Radiosonde auto rx project installation

Like r2could for satellites, the radiosonde auto rx software allows to receive and display on a map the position of weather radiosondes sent regularly.

Radio test with Rpitx

In the tutorial of part 9, the aim is to implement a test bench to receive the radio frequency signals emitted by the Raspberry PI. Indeed, it has a specific output (GPIO 4) that can be used directly on an antenna. The Raspberry Pi can manage frequencies from 5 KHz to 1500 MHz.

The software suite managing the Raspberry PI internal RF transmitter called rpitx, is designed by Evariste Courjaud F5OEO.

Conclusion

It’s a real shame that this environment is exclusively the business of IT specialists, because it deserves to be more democratized. I have often tested installation procedures from websites or even very recent books with often very mixed success. Hence the interest of radio clubs where someone who has already done the manipulation will be able to provide help. Without the information remaining « word of mouth », think of making a complete PDF installation sheet from scratch by publishing it on the site of the club concerned.

Through this tutorial, I hope to have answered the following questions:

This will avoid a real police investigation in order to cross-reference various sources of information to successfully install the program(s). As far as possible, I will check the proposed procedures periodically, as the Raspbian operating system is constantly evolving.

73 and have fun with Raspberry Pi

Anthony

F4GOH – KF4GOH

Publicités

Publicités