Transmitting WSPR Reports

The WSPR (Weak Signal Propagation Reporter, pronounced ‘whisper’) radio transmission technique was developed to enable considerable distances to be spanned using low power and minimum bandwidth. This article shows how you too can transmit WSPR reports using the Elektor SDR Shield and free software.

This is a submission from Rutronik on the compact wireless transceiver module TCM 515. This module is suitable for systems such as transceiver gateways, actuators and controllers that communicate based on the EnOcean radio standard in the sub-GHz band. It provides reduced power consumption, smaller size and a lower purchase price compared to the previous generation TCM 310, which is still available.

For aircraft enthusiasts and in particular plane spotters, it’s always interesting to listen to communications between aircraft and control towers. This receiver makes it easy to listen to all traffic in the civil aviation band. It is easy to build, has only one hardware adjustment, and can even be controlled from a PC with a USB port.

A new wireless transceiver invented by electrical engineers at the University of California, Irvine, boosts radio frequencies into 100-gigahertz territory, quadrupling the speed of the upcoming 5G wireless communications standard.

Author Burkhard Kainka’s inspiring Foreword in the book I’m reviewing here has important clues as to why software defined radio (SDR) is a hit not only among existing radio amateurs. SDR has proven to be a great promotion tool for the declining radio hobby in general. Since the tuning and decoding of shortwave radio signals is now done with a minimum of hardware and powerful (free) software, it’s easy to see why newcomers to the radio hobby and others with “DC minds” or with “deep fears of RF” have been totally captured by the concept of SDR.

How do you receive RF signals like FM radio or traditional broadcast television? Since this is Elektor it’s much more interesting to use a dipole antenna instead of a dedicated wire connection like cable or the Internet. A dipole antenna works by generating small amounts of current in the presence of an electric RF field which is then sent to the receiver using two-wire conductor called twin lead cable which is a balanced antenna cable. Let’s take a look at what makes this cable so special.

A Raspberry Pi plus a homebrew HAT with driver software and a custom graphical user interface created especially for this application combine to make a unique FM radio that is not only eye-catching but a fascinating learning experience, thanks to extensively detailed documentation. Nobody can fail to learn something new from this wide-ranging project!

This concluding part of our series on the Elektor SDR Shield 2.0 [1] is also the start of a new beginning. This automatically tunable receiver with two controllable VFO outputs opens up countless new opportunities, several of which are discussed in the article.

According to the US National Toxicology Program, radiation emitted by cellphones is safe for humans, according to recent studies in rats and mice...

Antennas are back magic to many electronicists and to hear that antennas may detune in the presence of metal is a further argument to leave all that “RF wizardry” to the specialists. And you can, safely. Antenova, winner of an Elektra 2017 award, can now supply a 2.4-GHz antenna which is designed to operate without de-tuning on metal surfaces or where the product housing is mainly metal. The antennas from the ‘Reflector’ range consist of two layers, one electrically isolated from the other, so as to provide RF shielding to the second layer. As a result the antenna can be placed on any kind of material and it will radiate effectively in the direction pointing away from the base material.