VOA Radiogram is a Voice of America program experimenting with digital text and images via shortwave broadcasting. It is produced and presented by Dr. Kim Andrew Elliott.

VOA Radiogram transmission schedule
(all days and times UTC):
Sat 1600-1630 17860 kHz
Sun 0230-0300 5745 kHz
Sun 1300-1330 6095 kHz
Sun 1930-2000 15670 kHz
All via the Edward R. Murrow transmitting station in North Carolina.

To decode the digital text and images transmitted on VOA Radiogram, download Fldigi, Flmsg and Flamp from w1hkj.com. See also how to decode the modes.

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  • Radio Australia MFSK text copied 100% in Greece, despite terrible signal

    Merkouris in Thessaloniki, Greece, received the Radio Australia MFSK test transmission 19 May 2013 at 0830-0835 UTC on 11945 kHz. Because Greece is well outside the Pacific target area, the signal quality was very poor (listen here), which was very good for testing digital text modes. 

    The voice content, barely audible after the MFSK ended, is not intelligible. But MFSK16 was copied 100%:

    image

    And MFSK32 about 97%:

    image

    The MFSK32 Radio Australia logo was a bit fuzzy, though:

    image

    • 2 hours ago
  • Radio Australia MFSK tests are successful

    The first Radio Australia test of digital text was successful. It was 18 May 2013, 0830-0835 UTC on 7410 and 11945 kHz.

    I saw reports of 100% copy on 11945 from listeners in Germany and Kansas City: pretty good range for one transmitter and one frequency.

    In norther Virginia, I listened and decoded on 7410 kHz because it was the signal coming in less well. Despite a fair-to-poor signal level, and a Cuban jammer on adjacent 7405 (listen to and decode audio here), copy of both MFSK16 and MFSK32 text was 100%.

    image

    Because the broadcast started a bit late, it ended just as the MFSK32 image was beginning. After the text, Radio Australia switched back to a sporting event. The audio gives you an idea of how a voice broadcast sounds given the same reception conditions.

    Roger in Petersberg, Germany, provides this image of his reception on 11945 kHz.

    Peter Marks in Sydney wrote this blog post about  the Radio Australia digital text test, and he produced this YouTube video.

    The MFSK32 image was included during the transmission at 1230-1235 UTC on 9580 kHz. This is what it looked like in northern Virginia. A bit rugged but not bad for half way around the word:

    image

    My text copy on 9580 kHz was 100%. This is what it looked like when MFSK16 switched over to MFSK32: 

    image

    Reception by Omar Alfredo Ortiz in Bogota, Colombia, 18 May 2013 at 0830 UTC on 11945 kHz in this YouTube video.

    • 2 days ago
  • More SSTV on VOA Radiogram May 18 and 19

    On VOA Radiogram for the weekend on 18 and 19 May, we will continue to experiment with images. In fact, we will transmit the same picture three ways: in two SSTV modes and then as an MFSK32 image. Bring something to read, or an electronics project, because these picture transmissions will take 4 to 5 minutes each.

    To decode the SSTV modes, several software programs are available. They include the RX-SSTV (receive only) from http://users.belgacom.net/hamradio/rxsstv.htm , MMSSTV from http://hamsoft.ca/pages/mmsstv.php , and Digital Master 780, part of the Ham Radio Deluxe suite, from http://www.hrdsoftwarellc.com .

    Before the images will be two VOA news stories in MFSK32 text, with the usual center audio frequency of 1500 Hz. The second story is in French, as we continue to determine if accented letters appear correctly on your display.

    To view accented characters in Fldigi: Configure > Colors & Fonts > next to Select Char Set, select UTF-8. To keep your selection of UTF-8, under Configuration, click Save Config.  

    Here is the lineup for VOA Radiogram the weekend on 18 and 19 May:

    2:55        MFSK16 Program preview

    1:59        MFSK32 VOA News in English

    4:03        MFSK32 VOA News in French

    1:07        MFSK16 Intro to SSTV transmissions

    4:31        Scottie DX SSTV

     :10        Tone (to give you time to save your Scottie DX image)

    5:08        Pasokon P5 SSTV

     :25        MFSK16 intro to MFSK32 image

    4:07        MFSK32 image

    1:10        MFSK16 closing announcements

    1:22        Surprise mode of the week (mixes somewhat with the closing music)                                   

    On VOA Radiogram during the weekend of 25-26 May, we will experiment with the Easypal digital SSTV mode, comparing it to MFSK32. Please download Easypal from http://vk4aes.com . Easypal images are transmitted by radio amateurs on 14233 kHz.

    VOA Radiogram transmission schedule

    (all days and times UTC)

    Sat 1600-1630 17860 kHz

    Sun 0230-0300 5745 kHz

    Sun 1300-1330 6095 kHz

    Sun 1930-2000 15670 kHz

    All via the Edward R. Murrow transmitting station in North Carolina.

    • 4 days ago
  • More Hell this weekend on The Mighty KBC


    The Mighty KBC will transmit the Hell 80 mode at about 0133 UTC on Sunday 19 May (9:33 pm EDT Saturday), centered on 1500 Hz. This is during its North America broadcast Sunday at 0000-0200 UTC on 9925 kHz via Nauen, Germany.

    At just before 0200 UTC, images in MFSK32 will be centered on 1000 and 2000 Hz. 

    • 4 days ago
  • Radio Australia digital text and image May 18 and 19

    For the first time, Radio Australia will broadcast digital text and images. This will be Saturday 18 May and Sunday 19 May 2013.

    UTC               Frequency (kHz)   Target

    0830-0835      7410 & 11945        south-west Pacific

    1230-1235      9580 & 12095*        south Pacific

    *Glenn Hauser believes this should actually be 12065

    As is characteristic of shortwave, reception outside the nominal target areas is likely.

    Each five-minute broadcast will include:

      :34 RA tuning signal (still Waltzing Matilda?)
      :05 Tone 1500 Hz
    1:42 MFSK16 text
    1:42 MFSK32 text
      :55 MFSK32 image
     
    All modes are centered on 1500 Hz

    The Radio Australia digital transmissions can be received on any shortwave, even if it does not have single sideband capability. Patch audio from the radio to a personal computer, and use software to decode the modes. For more information, see how to decode the modes.

    image

    • 4 days ago
  • Scottie DX SSTV images on VOA Radiogram

    Our experiment with the Scottie DX SSTV mode over the weekend of May 11-12 brought mixed results.

    There were some impressively clear images. The picture is  a shortwave curtain antenna in North Carolina of the type used to transmit this SSTV picture.

    For example, this from Hugo in Veurne, Belgium, 15670 kHz:

    image

    And from Marco, IK0DWN, in Rome, 17860 kHz:

    image

    And from Harald, DG0OCS, in Thuringia, Germany, 17860:

    image

    And from Mauno in Finland on 15670 kHz:

     image

    From Michael in Eschborn, Germany, on 17860:

    image

    From Tarmo, ES5NHC, in Estonia, a more impressionist SSTV image on 17860:

    image

    And from Bruce, N0NHP, in Colorado, a more Dadaist SSTV image on 17860:

    image

    image

    • 1 week ago
  • VOA Radiogram, May 4-5, via shortwave, then via YouTube

    Four YouTube videos demonstrate the reception and decoding of VOA Radiogram from the weekend of May 4 and 5 2013.

    Two are from Andy, N9VT, near Fredericksburg, Virginia…

    5745 kHz:

    www.youtube.com/watch?v=fjqCzhLPYH8

    6095 kHz:

    www.youtube.com/watch?v=dTioSlwgcVw

    Hugh Stegman of Monitoring Times Utility World shows how Flamp worked during his reception in California on 5745 kHz:

    www.youtube.com/watch?v=1Q0k9uFykvk

    image

    Craig, AV4M, in Tennessee, produced this video of the entire broadcast on 15670:

    www.youtube.com/watch?v=a3qFP6WD4Nk

    • 1 week ago
  • VOA Radiogram images as received in Slovakia

    Dezider, OM5NA, in Slovakia, provided these screenshots of his MFSK32 image reception on 4 and 5 May 2013, on 17860 vs 15679 kHz:

    Audio of Dezider’s reception of the entire VOA Radiogram on 15670 kHz is available at his SoundCloud page.

    • 1 week ago
  • VOA Radiogram: The rule of FUM (Fastest Usable Mode)

    Thanks to everyone who sent reception reports, screenshot, audio samples, and other attachments after listening to VOA Radiogram during the weekend of April 27-28.

    After six weeks of experimenting with digital text modes, I think we can conclude that the PSK modes are good, MT63, Olivia, and Thor are better, but MFSK remains the best.

    We can coin a new acronym: FUM — Fastest Usable Mode. It appears that these would be our FUMs:

    • MFSK16 (58 wpm): when poor reception conditions are expected
    • MFSK32 (120 wpm): when fair reception conditions are expected
    • MFSK64 (240 wpm): when good reception conditions are expected
    • MFSK128 (480 wpm): when perfect reception conditions are expected (eg local FM or AM)

    During reception of the Sunday 1930 UTC broadcast on 15670 kHz, I experienced a poor signal (being in the skip zone), moderate fading, and local noise. Excellent conditions to test digital text modes. This audio excerpt shows how MFSK16 provided a perfect decode even in these conditions. The Fldigi readout is below, showing MFSK64 on top, MFSK16 on the bottom:

    image

    image

    • 3 weeks ago
  • VOA Radiogram: Flamp worked. Except when it didn’t work.

    In the April 27-28 VOA Radiogram, a VOA news story was transmitted using Flamp, a program that accompanies Fldigi. Flamp divides text or any type of file into a certain number of blocks, each with a certain number of characters. Then it transmits the file more than once, with subsequent transmissions filling in any blocks that did not have the correct number of characters during the first pass.

    To test Flamp, I used the MFSK128 mode. This mode is very fast, thus prone to errors, hence useful for experimentation with Flamp. My own reception of VOA Radiogram on April 28 at 1300 UTC on 6095 kHz provided a textbook example of how Flamp works. After the first of two transmissions, three blocks were missing, i.e. rejected because they had the wrong number of characters :

    image

    Then all of the text was transmitted again. Flamp filled in the blocks that were missing:

    image

    The result was a perfect html file that could be saved, or pasted to a text editor, and opened in a web browser. The result looked like this:

    image

    Many listeners reported reception of a high percentage of the blocks after the second pass, but without 100% of the blocks received, the file could not be opened. This suggests that, next weekend, I should set Flamp to transmit three times. A 3X transmission of Flamp will take more time, so the question for us is whether the slower but more robust MFSK64 transmitted once is a better solution than MFSK128 transmitted multiple times.

    For some listeners, Flamp did not work at all. One cause for this is that the beginning code was not not received correctly (“header corruption”). It should look like this:

    image

    Any actual use of the Flamp concept in international broadcasting would require a software application that simplifies the process and places it in the background. 

    • 3 weeks ago
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