Friday, April 03, 2015

VOA Radiogram weekend programming



Hello friends,

The Saturday 0930-1000 broadcast of VOA Radiogram returns to 5745 kHz as of this weekend (4 April).


Yes, there were some breaks in transmission at the beginning of last week's transmission Sunday at 1930 UTC on 15670 kHz. It was not your receiver, computer, or software.

Last week's test of the 8PSK FEC modes was interesting. In general, the 8PSK FEC modes did not perform as well as well as the MFSK modes. However, Richard in New Brunswick and I, using a receiver in Nova Scotia, had 100% copy of all the modes, including 8PSKR250F at 635 wpm! This mode might be useful for high-speed data transmission, including formatted web pages, over distances of 1500 km or less, especially when propagation is stable.

This weekend we will do one more test of 8PSK125F. This will actually be two transmissions, one without the pilot tone, and one with the pilot tone. You do not need to make any adjustments to  detect the pilot tone, other than to have the Fldigi RxID on (green). "The RsID signal will both determine the mode and the mode center frequency (to the nearest 2.6 Hz). A finer resolution of the mode center frequency can be made using the optional pilot carrier," according to the Fldigi Users Manual.



Here is the lineup for VOA Radiogram, program 105, 4-5 April 2015, all in MFSK32 except where indicated ...

 1:27  Program preview
 2:46  Russia Denies License to Tatar-Language TV*
 8:53  8PSK125F: Tatar-language TV channels off air
10:03  8PSK125F (with pilot tone): Same story
11:08  MFSK32 resumes: Cyberattack targets GitHub*
16:39  Google and Chinese website certificates*
21:18  Cuba will increase Internet access*
27:10  Closing announcements
28:35  Bonus mode: Olivia 16-1000

* with image

Please send reception reports to radiogram@voanews.com .

VOA Radiogram transmission schedule
(all days and times UTC):
Sat 0930-1000 5745 kHz (new frequency)
Sat 1600-1630 17860 kHz
Sun 0230-0300 5745 kHz
Sun 1930-2000 15670 kHz
All via the Edward R. Murrow transmitting station in North Carolina.

The Mighty KBC will transmit a minute of MFSK64 Sunday at 0130 UTC (Saturday at 9:30 pm EDT) on 7375 kHz (via Germany). This is part of the expanded KBC transmission UTC Sundays at 0000-0300 UTC on 7375 kHz. The Saturday transmission of The Mighty KBC on 6095 kHz is discontinued.  Reports to Eric at themightykbc@gmail.com .

WRMI, Radio Miami International, 9955 kHz, will transmit IDs in digital modes again this weekend. You might not hear these transmissions, or even see a trace of the digital modes on your waterfall, but you might still successfully decode the text. Reports to Jeff at info@wrmi.net .

UTC Day  UTC Time  Center audio frequency  Mode
Saturday  1014:30  2000 Hz  MFSK32 image
Saturday  2129:30  2000 Hz  MFSK16
Sunday  0129:30  2000 Hz  MFSK32
Sunday  0329:30  1500 Hz  Olivia 32-2000
Sunday  1039:30  2000 Hz  MFSK32 image
Sunday  2259:30  2000 Hz  MFSK16
Monday  0059:00  2000 Hz  MFSK32
Monday  0329:00  1500 Hz  Olivia 32-2000

AndFlmsg (Fldigi for Android). If you have an Android tablet or phone, a new beta release (B0.5.0) of AndFlmsg  is now available at  http://www.w1hkj.com/vk2eta/ . This new version can decode MFSK images and has other improvements. Please let me know your results. (This tip from the developer: On the modem screen, to copy and paste part of the decoded text, simply stop the modem with the Modem On/Off button, then long-press on the received text to show the select/copy tool. The text can then be pasted into an email app for example.) (AndFlmsg B0.5.0 may not yet have the 8PSK125F mode.)

Thank you for your helpful reports from last weekend's broadcast (program 104). I will compile the gallery of MFSK images and answer those reports as soon as I can.
Kim

Kim Andrew Elliott
Producer and Presenter
VOA Radiogram
voaradiogram.net