![]() FT8 is also extremely popular on the 6 meter band, so there are many opportunities for long-distance communication even with a Technician Class License. With FT8, activity is limited to a narrow band of frequencies, so it is ideal for use with loop antennas that require retuning when changing frequency, such as CHAMELEON ANTENNA F-Loop 2.0 Portable HF Antenna ( CHA-F-LOOP-2-0). With its popularity, quickly working DXCC or WAS with FT8 is easily within reach of almost any station. This means that even low-powered stations and stations with sub-optimal antennas can make contacts worldwide. Why would I want toįT8 is designed to maximize communication even when signals are very weak (as low as -24dB). FT8 is one of a group of Multiple Frequency-Shift Keying (MFSK) modes that include JT9, JT65 and MSK144 created by Joe Taylor, K1JT and co-developers. and even older hardware-based modes such as RTTY that we now use our computers to encode and decode. Message into audio tones that are sent out via your sound card to your radio’sįor years there have been a variety of these new software modes including Phase-shift keying (PSK31 & PSK 65), Hellschreiber, Olivia, Pactor, etc. Conversely, when you want to transmit, the software encodes your ![]() Radio to be processed by software to decode the information embedded in the (SCM) because they utilize a computer’s sound card to bring in audio from your Wondering how to get started and why you would want to?įT8 is one of the many digital modes often referred to as sound card modes As one of theįastest growing modes of Amateur Radio it has been hard to miss, but you may be Good places to find these are in the Amateur Radio Bands around 3500-3550 KHz and 7000-7050 KHz.I am guessing that most of you reading this have either heardĪbout FT8 from fellow Hams or heard it on air as that strange repetitiveīuzzing sound between the CW and SSB portions of the bands. Start Cubic SDR, set mode for LSB, and tune in a CW signal.In the following example, we run CubicSDR and use FLdigi to decode CW tapping the audio out from CubicSDR via the “Built-in Audio Analog Stereo” interface. For Linux there is a hidden device called “Built-in Audio Analog Stereo.” Setup and Use The RTL-SDR site provides easy instructions on how to enable the hidden device under Windows 7. In Windows you will find a hidden recording device called “Stereo Mix” that can be used. To pipe audio-out from one application to audio-in of another application we need to setup an intermediate sound interface. Otherwise leave callsign blank and click next through the wizard screens insuring at the Audio Device screen PortAudio is checked and the relevant sound card is selected. If you have an Amateur Radio license, answer the relevant files in the questions presented. For Linux releases, search and install Fldigi from your distribution repository.įirst time you run Fldigi you will be walked through the installation wizard. You can download the Windows or Mac OSX versions and run to install. Since RTL-SDRs are not transmitters, we will be receiving only. In essence, Fldigi allows your soundcard to be used as a modem for receiving an sending a range of digital modes. Fldigi is comprehensive in the range of digital modes it is capable of decoding and is available on Windows, Linux, and OSX. The digital modes you most readily find and able to decode on HF are used in Amateur Radio. ![]() ![]() It doesn’t matter whether you follow the client/server use model I run with or connecting a RTL-SDR dongle directly to your machine with the SoapySDR drivers, decoding digital modes is the same since we are working with the audio out of the SDR application. A previous post of mine goes into how to install it across platforms. CubicSDRĬubicSDR will be our SDR application of choice. We will stick with using cross-platform applications for Linux, Mac OSX, and Windows. Let’s start with the software applications we will be using and then with how piping audio from one to the other is done. Some SDR applications have plugins to facilitate decoding but may have complex dependencies tp be pre-installed/comfigured (SDR# comes to mind.) For this post I am going to focus on decoding the more popular digital modes you will find on HF by piping audio-out from from the SDR application to audio-in on a decoder application. While hearing shortwave broadcasts, trans-atlantic aviation, and Amateur Radio conversations are interesting, there are a number interesting digital mode signals to tune into. In previous posts I’ve showed how to build a network accessible SDR server and tested SDR client applications running on Linux, Mac OSX, and Windows.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |