Decoding the SW Radiogram Broadcasts
From The RadioReference Wiki
- 1 What Kind of Radio Do I Need?
- 2 What About Antennas?
- 3 How Can I Get a Better Signal?
- 4 Where Can I Get the Schedule and Frequencies?
- 5 How Does the Signal Get to Me, Anyway?
- 6 I Understand You Can Use an Android Device to Decode the Broadcasts?
- 7 How Do I Get the Audio From My Radio (or SDR) To The PC?
- 8 What is this DRM listed on the WINB schedule? Can I Tune This or Decode it?
- 9 What Modes Are Being Used?
- 9.1 Where Can I Find Compatible Software to Copy These Broadcasts?
- 9.2 How do I configure the RSID feature to work with the SW Radiogram Broadcasts?
- 9.3 How do I decode the signal when the center frequency drops to a very low level (i.e. 65 hz)?
- 9.4 My Images Decoding with MFSK Are Slanted
- 9.5 Are There Any Examples of These Applications In Actual Use?
- 10 Does This Program Have A Social Media Site?
What Kind of Radio Do I Need?
Just about any radio that covers the 2-30 Mhz range is capable of receiving these stations. It should be reasonably stable, selective and sensitive. This encompasses a wide range of radios, everything from portables, such as those from Tecsun and Degen, all the way to Software Defined Radios (SDR) such as the SDRPlay and Perseus. Even wide band radios like those from Icom and AOR can be used. It doesn't need to be expensive. To begin your research, see our HF Equipment and Accessories and Software Defined Radios articles.
What are some examples of portables used to receive the SWR broadcasts?
These are just a small sample of the portables reported to be used on the SWR Facebook and Twitter pages. There are numerous others, and the reader is encouraged to research these and other radios using the resources mentioned above.
- CountyComm GP-5/SSB
- Grundig G5
- Grundig S450DLX
- Kaito KA1103
- Radiowow R-108
- Sangean ATS-909X
- Tecsun PL-660
- Tecsun PL-880
- XHDATA D-808
I Dont Have A Radio Yet. Can I Use a Web Radio?
Yes you can. If you don't have the Stereo Mix app on your PC, you will need to install software like Stereo Mix Plus to route the audio from your speakers to the soundcard. You can find some online networks in our Live Tunable Receivers article.
What About Antennas?
It's been often said that the better the antenna, the better your results. Unfortunately sometimes that is difficult to obtain; you may be in a situation where outdoor antennas are not allowed, or you have very little space with which to work. What radio you are using, your budget and circumstances will play a large role in what you can use. Read our Basic HF Antennas article for a discussion on this topic.
How Can I Get a Better Signal?
If you have done as much as you can with your radio and antenna, but are still not satisfied with your results, there may be some more than you can do to improve your chances. See our Improving HF Reception for a discussion on this topic.
Where Can I Get the Schedule and Frequencies?
Take a look at the Shortwave Radiogram website. This is where the program for the week, along with the schedules and frequencies are posted. They are also repeated on mailing lists such as World of Radio (WoR) on groups.io
How Does the Signal Get to Me, Anyway?
We are very much at the mercy of the Sun when it comes to how signals get propagated across the globe. Unfortunately, as of this writing, we are in a very low period of solar activity, so we must depend on better radios and antennas to help. However, an understanding of how a signal propagates through the ionosphere is very important; this will help you to understand why a signal can be heard at some times but not others. See the AE4RV Propoagation Primer for a basic discussion on this topic. Be sure to turn your flash player on before looking at this site.
I Understand You Can Use an Android Device to Decode the Broadcasts?
Yes, the application is called TIVAR. To learn where to get it, and see how to use it, please see the Decoding the SW Radiogram Broadcasts with TIVAR article
How Do I Get the Audio From My Radio (or SDR) To The PC?
This is a topic that is difficult to define simply, as there are so many possible ways to connect the two together. The method used for connecting a portable radio or desktop is very different how you would connect a Software Defined Radio (SDR). See the Connecting Radios to Soundcards article for an extensive discussion on this topic.
What is this DRM listed on the WINB schedule? Can I Tune This or Decode it?
DRM stands for Digital Radio Mondiale, a method of increasing the fidelity of a HF signal. Most any receiver will need a special modification to be able to decode this. It will otherwise sound like a loud hash. See our DRM article for more information on this mode.
What Modes Are Being Used?
There are literally hundreds of different modems being used on the HF spectrum. Here, we are concerned with modes that are used in the amateur radio (ham) community, as software for these modes is readily available.
- From the Signal Identification Wiki
- Other Sources
Where Can I Find Compatible Software to Copy These Broadcasts?
While FLDigi is the most popular software used for this, it's not the only one that's capable of decoding these broadcasts. All of these applications recognize the use of the RSID to aid in recognizing the mode that is being sent. Questions or issues with the software should be directed to the indicated mailing lists, where specific help is available.
- W1HKJ home page - home for FLDigi
- FLDigi Downloads Sourceforge site
- Ham Radio Deluxe (includes DM780)
How do I configure the RSID feature to work with the SW Radiogram Broadcasts?
- First a little background information; while the RSID is sent at an audio frequency of 1500 hz, there is a 1000 Hz tone start up tone that might confuse the decoders. This could be one reason why if you set this up to record automatically, you might not get a decode.
- DM780 (Ham Radio Deluxe)
- The following Youtube video shows how to set up the RSID. Specifics on how to set it up for SWR are solicited
- 2 steps are required to set the RSID. See the image for what needs to be entered. The image comes from the old VoA Radiogram website
- To access the form on the right, select Configure / Other / ID. Hit Save when you are done.
- To access the form on the left, select Configure / Other / Notifications. If you wish to create the macros, use the text box the purple arrows are pointing to. Be sure to hit Add or Update then Close
- The screen shot is accessed from the RX/TX screen. See Configuration / Management of the identifiers. Set Detection Mode to Continuous and set Modes to All
How do I decode the signal when the center frequency drops to a very low level (i.e. 65 hz)?
- Most soundcards won't go down below 200 Hz or so. To get around this, you must use a sideband capable radio or a SDR. Listen in either USB (preferable) or LSB. On LSB you must tune 1 kHz higher. On USB you must tune 1 khz lower. Because AM signals have two sidebands, the 65 Hz signal then becomes 1065 Hz and 935 Hz, and the AM carrier becomes 1000 Hz (which is the amount by which you offset your tuning), which you will also hear. So you will actually get three signals, the 1065 Hz signal is useful for decoding; the 935 Hz tones will be REVERSED.
- The problem is mostly due to the IF and demodulator filtering. Many SSB receivers have a low passband edge of only 300 Hz, and some AM receivers have a highpass of 150 Hz. This applies during demodulation (like when making an audio recording or performing a live decode, or when demodulating an IQ recording to audio for decoding.)
- Another method you can try with FLDigi;
- Select the correct "Op Mode"
- Use the waterfall's cursor and signal on a low frequency below the first tic mark.
- Use the fine frequency arrow (found at the bottom center of the waterfall) to fine tune the frequency. The blue pen is indicating the rough frequency selection.
- See this YouTube Video with an example (using QPSK63) of how this works.
My Images Decoding with MFSK Are Slanted
- If you are copying images using MFSK and they appear slanted, you will need to apply a correction. Several digital decoding programs have this capability, and they are described in the links below;
Are There Any Examples of These Applications In Actual Use?
These are YouTube videos with examples of each application above being used to decode an actual broadcast. There are many other examples on YouTube and a well formatted search will bring them up
- Using DM780 (Ham Radio Deluxe)
- VoA Radiogram 7th july 2013
- 15670 kHz USB - VOA Radiogram - MFSK Transmission - 9-15-2013 19:51 UTC
- Voice of America Radiogram - Sept.22, 2013 19:55 UTC
- Using FLDigi
- Receiving image in the Shortwave Radiogram 9400 kHz with Fldigi
- Shortwave Radiogram #84 Jan 25 2019 on 7780Khz Shortwave Radio R8600
- Decoding Shortwave Radio Gram using GQRX and FLDigi
- Shortwave Radiogram Program 98- Fldigi settings
- Using MultiPSK
- Decoding Shortwave Radiogram 26 in MFSK32 Dec 16 2017 on 9400 kHz with Multipsk
- Shortwave Radiogram #36. Received & recorded in Germany on 9400 kHz. Decoding with Multipsk
- SW Radiogram #33 on 9400 kHz shortwave received with AFEDRI SDR, MFSK32 decoding with Multipsk
Does This Program Have A Social Media Site?
- Both Facebook and Twitter are used; These sites are also used to display decoded images