There are several steps required to get ready to receive radiogram signals.
The decoding software for Radiogram transmissions is called FLdigi (other programs can also be used). This can be downloaded from: sourceforge.net/projects/fldigi/files/. Select fldigi.exe and download to your computer. The software was developed by and American amateur radio operator W1HKJ and is free to use. Anroid devices require free decoding software called TIVAR.
Its important not to miss the beginning of a radiogram broadcast. The RSID instruction (it forces FLdigi to the correct decoding mode automatically) is transmitted the begining of the broadcast and also whenever the mode is changed. For this to work correctly the RRXiD button in the top right hand corner of the FLdigi screen must be selected (turns green when activated).
For those using an Android phone, TIVAR is all that is required. Simply tune to the Radiogram frequency at the appropriate time, start the TIVAR application and place your phone near the receiver speaker. Images and text should be decoded if you can receive the signal.
In order to couple the receiver audio into your computer (via the line input socket on the soundcard and the line output or speaker socket on the receiver), you will need to download a free “Virtual Audio Cable”. This is simply an electronic software connection inside the computer to connect the receiver audio to the decoding software.
If using a laptop, simple “acoustic” coupling is all that is required, using laptop microphone.
If your receiver doesn’t have a line output socket, you can still use the speaker output but you wont be able to listen to the radio signal, unless you use a Y cable or adaptor. These are normally sold as a 3.5mm stereo plug to 2 mono RCA sockets or plugs. Electronic parts suppliers such as Jaycar sell such items (cat # WA7014, WA7404, PA3580 and PA3582 are amongst suitable adaptors.
You can down load a virtual audio cable from: https://www.vb-audio.com/Cable/. This software is not freeware and all support contributions by way of donation, are accepted. Simply download the zipped folder to anywhere on your computer and select : VBCABLE_Setup_x64.exe. For older computers (32 bit) select: VBCABLE_Setup.exe
When receiving a Radiogram signal, select “VB Audio Virtual Cable” from your computer speaker selection.
If you don’t have a shortwave receiver, or you live where no shortwave reception is possible, its also possible to enjoy receiving radiogram signals via an on line SDR. Simply logon to the SDR ( go to https://sdr.hu/ for a worldwide list), select an SDR located close to the transmission source (either Florida or Bulgaria in this case), select AM mode and the desired frequency. Then select the Virtual Audio Cable in your computer speaker selection) and open FLdigi.
FLdigi has a function that can automatically optimise all parameters for the incoming signal. Just click on RxID in the upper right hand corner of the screen, before the broadcast starts.
You should begin receiving text and images (there is a schedule available at swradiogram.net/) during the 30 minute broadcast duration.