May 2013
8 posts
VOA Radiogram for the weekend of May 25-26...
On VOA Radiogram the weekend of May 25-26, we will continue our experiments with images via shortwave broadcast. The MFSK32 and SSTV modes are analog. Now we will try purely digital images using EasyPal software.
Download EasyPal from vk4aes.com. After EasyPal is installed, go to Setup > Setup c/s-soundcard-PTT > Soundcard and select the soundcard you use to receive VOA Radiogram.
In...
During the weekend of May 18-19, VOA Radiogram was...
With the 17-year cicadas making their appearance in the eastern United States, VOA Radiogram for the weekend of May 18 and 19 included a picture of a cicada (actually a 13-year cicada from 2011). The picture was transmitted using three modes: SSTV Scottie DX, SSTV P5, and MFSK32.
Lorenzo in Italy sent these images from his reception on 17860 kHz: Scottie DX, P5, MFSK32:
Corrado in...
YouTube video of VOA Radiogram as received and...
Lorenzo in Italy (near Rome) produced this YouTube video of the entire VOA Radiogram on 18 May 2013 at 1600-1630 UTC in 17860 kHz.
It even includes the VOA French newscast beginning without accents displaying, during which Lorenzo changed the character set in Fldigi, with the accent showing correctly thereafter.
www.youtube.com/watch?v=YNID1UsZsOY
Andy in Fredericksburg, Virginia,...
Radio Australia MFSK text copied 100% in Greece...
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%:
...
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...
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:
And from Marco, IK0DWN, in Rome, 17860 kHz:
And from Harald, DG0OCS,...
VOA Radiogram, May 4-5, via shortwave, then via...
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...
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.
April 2013
18 posts
VOA Radiogram: The rule of FUM (Fastest Usable...
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....
VOA Radiogram: Flamp worked. Except when it didn't...
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.
...
A solution to uneven line breaks
I’ve noticed in the text “dumps” sent by many VOA Radiogram listeners that the line breaks are uneven. This happens when the received text is copied from Fldigi or other decoding software and pasted into a text editor or word processor.
The problem was that I was pasting text with no line breaks into the Fldigi output window. The solution, suggested to me by Christopher,...
VOA Radiogram: YouTube from Italy of decoding on...
IK1RKU in northern Italy provided this excellent YouTube video of the entire VOA Radiogram transmission on 20 April 2013, 1600-1630 UTC, on 17860 kHz:
www.youtube.com/watch?v=Fnw4yu4SGbo
And another YouTube recording of an entire VOA Radiogram by Andy, N9VT, in Fredericksburg, Virginia. This is from 21 April 2013, 0230-0300 UTC, on 5745 kHz. Reception quality was obviously not a...
VOA Radiogram for April 27/28 includes Thor50x2,...
Apologies for not updating this website since the April 20/21 VOA Radiogram. I have been diverted by deadlines connected to my other full-time job, audience research analyst for the International Broadcasting Bureau.
Thanks to all who sent reception reports, screenshots, audio samples, and other materials from the past weekend’s program. MFSK held off a challenge from the Thor modes and...
Thor 50x2 this weekend on The Mighty KBC
The Mighty KBC, based in the Netherlands and transmitting via Germany, will include digital text modes in its North America broadcast, Sunday 28 April at 0000-0200 UTC (Saturday evening 8-10 pm EDT) on 7375 kHz.
At about 0133 UTC, the Thor 50x2 mode will be centered on 1500 Hz. At just before 0200 UTC, MFSK32 text will be centered on 1000 Hz, and an MFSK32 image on...
The results so far
Thanks to everyone who has sent reception reports, audio samples, screenshots, and other interesting materials. After the program on the weekend of April 13-14, featuring the Olivia modes, we heard from listeners in Austria, Belgium, Canada (BC and Ontario), Colombia, Finland, France, Germany, Italy, Russia, Sweden, UK, and Ukraine, as well as from the US states of Arizona, Arkansas, California,...
VOA Radiogram as received in Bogotá
Omar Alfredo Ortiz in Bogotá, Colombia offers this recording of VOA Radiogram, 14 April 2013, 0230-0300 UTC, on 5745 kHz. You can do your decoding from Omar’s audio. We also like Omar’s keywords:
VOA Radiogram: YouTube video of the 1600 UTC...
Hugh Stegman, editor of the Utility World column for Monitoring Times magazine, produced this YouTube video of his reception of the final ten minutes of the 1600 UTC broadcast of VOA Radiogram on 13 April 2013, 17860 kHz. Hugh is in California.
And from ik1rku in Italy, this YouTube video of Olivia 16-1000 versus Nelson Riddle on 17860 kHz
VOA Radiogram: Good decodes from marginal...
Tomak in Krakow, Poland, does not have his digital decoding software working yet, but he did kindly send an mp3 audio file of his reception on 6 April 2013 at 1600 UTC on 17860 kHz.
We decoded the digital text from his audio file. Kim’s voice is barely intelligible, but the MT63-500 was decoded 100%, and the MFSK16 preceding it nearly so, despite deep fades on both text...
VOA Radiogram: Some details about the transmitters...
In response to questions about the transmission of VOA Radiogram from the Edward R. Murrow Transmitting Station in North Carolina, here are some details.
What kind of transmitter is used?
We are using GE 4BT250A1 250-kW transmitters for the VOA Radiogram programs. It is one of the original transmitters installed at the station in 1962.
What is the actual transmitted power?
The...
VOA Radiogram: More YouTube videos from Slovakia
Dezider Monoš, OM5NA, in the Slovak Republic has again produced YouTube videos of his VOA Radiogram decodes. These are from 7 April 2013, 1930 UTC, on 15670 kHz.
MFSK16:
youtu.be/FzjEotUuvX4
MT63-1000 (long):
youtu.be/FzjEotUuvX4?t=8m50s
MFSK64:
youtu.be/FzjEotUuvX4?t=11m40s
MT63-2000 (long):
youtu.be/FzjEotUuvX4?t=14m
MFSK32 image:
youtu.be/FzjEotUuvX4?t=22m20s
VOA Radiogram: Near-antipodal decode of MFSK...
This audio sent by John in Depok, Indonesia, provided a perfect decode of MFSK16 and nearly perfect decode of MFSK32. (Note that the voice portion of the broadcast was mostly unintelligible.) MT63-500 did not decode at all. Depok is 16700 km from the IBB shortwave transmitting station in North Carolina. Given the time and frequency, however, John’s reception was probably via the long...
From Slovakia, YouTube videos of VOA Radiogram...
Dezider Monoš, OM5NA, in Slovakia, produced two YouTube videos of his VOA Radiogram reception during the weekend of 30-31 March 2013. The first is 30 March 2013, 1600 UTC, 17860 kHz, showing his reception of MFSK64, PSKR500, MFSK128, and the two MFSK32 images: http://youtu.be/NHCChfZf_eI The second is 31 March 2013, 0230 UTC (4:30 am in Slovakia!), 5745 kHz, comparing PSKR500 and MFSK128...
More shortwave broadcasters experimenting with...
Radio 700 Kurzwelledienst
Radio 700 Kurzwelledienst in Euskirchen, Germany, a shortwave broadcaster using 1-kilowatt transmitters, is experimenting daily with the PSKR250 digital text mode centered on 2000 Hz: 0557 UTC on 6005 and 7310 kHz 1555 UTC on 7310 kHz 1655 UTC on 6005 kHz
See this YouTube video by DG0JBA showing the decoding of a Radio 700 PSKR250 transmission. PCJ...
One transmitter in North Carolina achieves perfect...
Merkouris Gogos in Thessaloniki, Greece reported perfect decode of the very fast (480 wpm) MFSK 128 mode on 31 March 2013 at 1930 UTC on 15670:
Mike Stapp in Minneapolis had perfect decode of MFSK 128, same time, same frequency:
It’s remarkable that one IBB transmitter in North Carolina, on one frequency, achieved perfectly decoded digital text at locations 8000 km apart.
...
VOA Radiogram: successful decodes with shortwave...
Some listeners used inexpensive portable radios to receive VOA Radiogram over the weekend. And they were able to achieve successful decodes of the text.
Andy Lawendel in Milan, Italy used a Tecsun PL660…
For this flawless decode of MFSK32 during the Sunday 1930 UTC broadcast:
In northern Virginia, my Tecsun R9700D, with analog tuning and whip antenna…
…managed 100%...
VOA Radiogram audio from the weekend (via Canada)
If you missed VOA Radiogram over the weekend, Chris near Toronto has recorded and posted two entire weekend airplays, along with audio from The Mighty KBC digital text tests:
https://soundcloud.com/swl0
Chris also shows what VOA Radiogram looks like on his WinRadio display just as the program signs on at 0230 UTC on 5745 kHz:
And later in the broadcast, at 0239, when digital text is...
March 2013
28 posts
YouTube videos of this weekend's digital text via...
Mark Webber, W4MRW, produced some excellent YouTube videos of this weekend’s digital text via analog shortwave broadcast. Each includes audio, the Fldigi printout, and the Flex-3000 SDR spectrum display.
Entire VOA Radiogram, 31 March 2013, 0230-0300, 5745 kHz:
https://www.youtube.com/watch?v=qxltfRIvjlw
Entire VOA Radiogram, 31 March 2013, 0230-0300, 6095 kHz:
...
The Mighty KBC: MFSK128 is not perfect, but 95% is...
On the Mighty KBC, 31 March 2013, 0133 UTC, 7375 kHz, an MFSK128 transmission resulted in about 95% copy in northern Virginia. Not bad for a 480 WPM mode. Transmitting it twice or three times with Flamp would likely result in 100% copy:
See also great YouTube video by Mark Webber.
VOA Radiogram reception in Germany at 1600 UTC,...
Uwe Wolk in Germany also had 100% copy of the Flmsg news story in MFSK64 during the 1600 UTC airplay on 17860 kHz:
Also excellent MFSK32 images:
Great reception of the 1600 UTC VOA Radiogram in...
Merkouris Gogos of Thessaloniki, Greece had 100% or 95% copy of all of the modes at 1600 UTC, including 100% of the very fast MFSK128.
Here is his reception of the MFSK64 transmission is Flmsg format:
And his copy of the photo of the airborne drone that accompanied the same VOA story:
VOA Radiogram in France on 17860Khz LOC:JN29HT
Picture received :
VOA Radiogram: In Oregon, 100% copy of MFSK64 on...
Hearing almost nothing here in northern Virginia, too close to the transmitter on 17860 kHz at 1600 UTC. But K6FIB in Oregon had perfect copy of the MFSK64:
And here is Fibber’s reception of the MFSK32 image. The horizontal line is where the signal quickly faded to nothing:
VOA Radiogram digital text survives low level...
Claudio in Italy kindly sent a recording of his reception on 24 March at 1930 UTC on 15740 kHz. Because we do not have the necessary HDSDR player, the playback audio level is too low to understand anything that Kim was saying. The tones, however, could be heard, just barely. And the tones could be decoded.This turned out to be a very good test of the capabilities of digital text via analog...
For best MFSK images, calibrate your soundcard
To ensure that the MFSK images from VOA Radiogram are properly aligned, i.e. not slanting (as below), it is useful to calibrate your soundcard.
A useful guide to soundcard calibration is provided by the Pennsylvania Situation Report.
Olivia 8-1000 versus the country hit "Someday...
On its North America broadcast Sunday, 24 March, at 0000-0200, The Mighty KBC featured text modes at about 0130 and 0200, on its 7375 kHz frequency via Germany. At 0130, Olivia 8-1000 was centered here, 24 dB under the country tune “Someday [garbled],” by Suzy Bogguss. (Audio here.) Well, close to perfect, and other listeners had 100% copy.
This coming Sunday on The...
The Mighty KBC, 24 March 2013, 0130 UTC,...
WRMI digital text ID decoded in Australia
The PSKR250 digital text ID of WRMI, Radio Miami International, 9955 kHz, was decoded on 24 March, 0900 UTC, by Peter, VK3RV, near Melbourne Australia. The copy is a bit garbled, but considering the distance and that Australia is far outside WRMI’s target zone, remarkable:
This is what the WRMI PSK63F IDs on 23 March sounded like and looked like in northern Virginia at 1330 UTC....
VOA Radiogram in YouTube videos
Florenzo, IZ1CQN, in Italy, produced two YouTube videos of his reception and decoding of VOA Radiogram on 24 March 2013 at 1600 UTC on 17860kHz.
PSKR125:
www.youtube.com/watch?v=HtwCdH7THZE
MFSK32 image:
www.youtube.com/watch?v=5yvoxhmdamg
Tony Roch in France made this video of his reception and decoding of the PSKR125 mode:
www.youtube.com/watch?v=Y7eDlMmo8aw
In Italy, perfect PSKR125 reception on a shortwave...
From today’s 1600 UTC broadcast, Max Scordamaglia in Italy sent this image of his perfect PSKR125 reception — many other listeners also had their best luck with PSKR125. What is notable about Max’s reception is that it was not on an expensive communications receiver or amateur radio transceiver, but on a consumer-level Sangean ATS-909 shortwave portable. (See the version of the...
From Arizona, great Flmsg copy, psychodelic...
During the 1600 UTC airplay on 17860, Dave Burnett in Tucson, Arizona, had good copy of the Flmsg-formatted VOA News story in the PSKR250 mode:
His reception of the MFSK32 image was, well, a bit funky:
VOA News, html-formatted, via shortwave, as...
The 1600 UTC airplay of VOA Radiogram was successfully received by listeners in Europe and in (mostly the western) USA
Franco Spinelli in Italy sent this image of the Flmsg-formatted VOA news story transmitted in PSKR250. When all the text received, it popped up as a new window in his browser. Decode was perfect, except the VOA News at the top is supposed to be blue, and the subheads should be...
WRMI, Radio Miami International, 9955 kHz, 23...
An example of success from the VOA Radiogram soft...
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...
Excerpt of VOA Radiogram, 17 March 2013, 1930 UTC...
MFSK64 versus PSKR250 on The Mighty KBC
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...
Reception of The Mighty KBC, 17 March 2013, 0130...
WRMI Olivia 8-2000 IDs on 16 March
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.
VOA Radiogram soft launch: thanks for all the...
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...
