PSK31 Audio Beacon     

PSK31 Beacon

Project Description

App #1: Tone Gen


Source Code

PSK31 Beacon



PCB Layout

Source Code

Programming the SX

Useful SX Links

SX28 Overview

Beaconing Guide

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Digital Homebrewing Home Page


This is the first general microcontroller QRP project that we're tackling as part of the QRP Quarterly column called Digital QRP Homebrewing.  As you'll recall from the Fall 2001 issue, we’ll use a popular and/or inexpensive kit from one of the QRP clubs to describe how you can add custom features or an entirely new program. We’ll show you the tools and steps needed to make these software mods, possibly add some extra hardware too, and probably learn something along the way!

This time ...
Right now we’ll use the PSK31 Audio Beacon Kit as the basis for our Digital QRP Homebrewing tutorial and experiments. Designed and kitted by the NJQRP Club, this $25 marvel contains a fast RISC microcontroller, a dirt-cheap D-to-A converter, and an LM386 audio amp.  The designer used these simple components to synthesize an audio carrier signal and then “PSK31 modulated it” with text data to create a “beacon”. Additionally, individual characters can be send to the board from keystrokes sent over a serial port to create a real time PSK31 audio encoder.

In these online web pages, we'll take this hardware and software system apart and show you how to modify it to create a simple new function: a simple tone generator.  Admittedly, this is a roundabout way to produce a tone, but the intent is to illustrate how one can use an inexpensive kit intended for one specific purpose and turn it into something else through your own ingenuity and creativity. If you regularly visit these pges, you'll see additional tutorials and experiments accumulate for this project board.

These pages are constructed in a manner that presents the related material in a list of links on the left side of the screen.  The base project (PSK31 Audio Beacon) material is presented in one grouping in order to provide the common information: schematic, board layout, theory of operation, etc.  The special application project (tone generator) material is presented in another group of links, providing access to the tutorial instructions, modifications and altered hardware and software in order for you to duplicate the experiments.

This kit was featured in August 2001 QST, and you can still purchase one from the NJQRP and play along with us here. Check out the Useful Links for details.

Page last modified: November 28, 2001

Copyright 2001 G. Heron, N2APB