From the VOA Radiogram “soft launch” on 16 and 17 March, listeners sent examples of less than perfect decodes, some much less than perfect, and  some pure gibberish.

We also had a some successes. One is contained in this excerpt of audio sent by Achilles Giagnis of Komotini, Greece, near the site of the old IBB Kavala relay station, and 8400 km from the IBB transmitter in North Carolina. This is from the transmission on Sunday, 17 March, at 1930 UTC on 15470 kHz. The PSKR125 mode centered on 2000 Hz provided 100% copy of this VOA news story:

We will try again this weekend with PSK modes.

On 17 March, The Mighty KBC, 7375 kHz via Germany, transmitted PSKR250 (220 wpm) centered on 1000 Hz, and MFSK64 (240 wpm) on 2000 Hz. The PSKR250 decoded less than 100% successfully, but the MFSK64 was flawless. Reception in northern Virginia (hear the audio) was on a $30 analog-dial portable with whip antenna.

The previous week on the Mighty KBC, the results were the same, even though the audio frequencies were reversed. So the factor was the mode, not the audio frequency. 

On Saturday, 16 March, WRMI, Radio Miami International, transmitted IDs in the Olivia 8-2000 mode. The text readout was perfect via a fair-to-poor signal…

At 1330, the copy was less successful, but given the quality of the signal and level of noise, not bad:

Note that WRMI is beamed to Latin America, not to the USA, and that its signal is jammed by Cuba.

I would like to thank all the listeners around the world who sent reports, audio, screenshots, spectrum displays, etc of the VOA Radiogram “soft launch.” I’m still absorbing all this material and hope to respond to your e-mails within a few days.

Success in decoding the PSK modes varied, as expected, by time, frequency, location, software, and hardware.

Some of you noted a low audio level. This should be improved next week, when the levels for both the tones and my voice will be increased. Also, we will transmit only one mode at a time. This will simplify your decoding, and allow us to concentrate all of the RF energy in one mode, thereby increasing the signal-to-noise ratio.

Next weekend’s VOA Radiogram will feature the BPSK and PSKR modes. I am starting with PSK because it is well known to the amateur radio community. While we had good success with BPSK and PSKR during the soft launch, these are not the most robust modes available to us. In future weekends, we will try MFSK, Olivia, MT63, and other modes that might better be able to withstand fades and other degradations of shortwave.

We hope the VOA Radiogram broadcasts will encourage the development of software applications for PCs and for mobile devices that will simplify the process of decoding the text transmissions. Perhaps future shortwave receivers will include a suitable display and the software for the reception of text and images.

For those who requested QSL cards, it may take a couple of weeks for those to be designed, printed, and mailed.

Information about next weekend’s VOA Radiogram will be posted soon.

Thanks again.

Kim Andrew Elliott

PS: See these YouTube videos of VOA Radiogram reception:

http://www.youtube.com/watch?v=fCW_iOoEfAE (Italy)

http://www.youtube.com/watch?v=MWbZs6jFkcA (Germany)

http://www.youtube.com/watch?v=KSwGAI39kfU (Slovakia)

http://www.youtube.com/watch?v=AEM8DhgX1cU

http://www.youtube.com/watch?v=Jd7uDj8Iznw

http://www.youtube.com/watch?v=GaTTG944c20

http://www.youtube.com/watch?v=0HSM4V_CyFU& (Mexico)

http://www.youtube.com/watch?v=Uqn8E70kKiI (Oregon)

To decode and read the VOA Radiogram text and image transmissions, you will need the following items:

1. A shortwave radio. The radio does not need to have single sideband (SSB) capability. Even if you do have SSB capability, listening in the AM setting will probably work best.

2. A basic personal computer. It does not have to be particularly powerful.

3. A patch cord from the audio output of the radio to the audio input of the PC. This is usually from the earphone jack of the radio to the microphone jack of the PC. If you do not have a patch cord, placing your radio’s speaker near the built-in mic of a laptop PC (“acoustic coupling”) might work. If your PC has one of those “combo” audio jacks, i.e. no separate mic jack, you will probably need a USB audio adapter (like this one or this) to give you a proper microphone input. Use of your earphone jack will probably mute your radio’s speaker, but you might be able to configure your PC’s audio settings to hear the audio from your PC’s speakers or through headphones connected to the PC. You can also use a Y adapter: send audio to your PC through one output, listen on an earphone through the other.

4. Software to decode the digital text. This includes the free Fldigi program (also download companion Flmsg and Flamp programs), as well as MixW, MultiPSK, DM780 (part of Ham Radio Deluxe), and others. Configure the software for the soundcard your PC uses. You might also have to go into your PC’s audio settings to select the correct record source. You should see a “waterfall,” showing audio from your radio, moving from top to bottom. A good way to test this is to find a station playing music. If you have a radio with SSB capability, tune to 14070 kHz USB and try to decode the BPSK31 amateur stations that are often heard on this frequency.