In the past few weeks, we have included the MFSK64 and MFSK128 modes in VOA Radiogram. These fast modes are useful for sending large amounts of information, including html coding. But they are often prone to errors if shortwave reception conditions are less than ideal.
To address that problem, the Fldigi development team has created long interleave versions of the two modes: MFSK64L and MFSK128L. They include a "6.25 second interleaver for very robust HF reception." The new MFSK64L and MFSK128L modes are available in the latest "alpha" version of Fldigi, 3.21.76AR, available from http://www.w1hkj.com/alpha/fldigi/v3.21/
During VOA Radiogram for the weekend of 26-27 October 2013, we will transmit the same VOA news story in the MFSK64 "short," then in MFSK64L. After that, we will do the same comparison with MFSK128 and MFSK128L.
When you are the w1hkj.com website, please also download the latest version of Flmsg: 1.1.33. In the past, diacritics and non-Latin alphabets would not display correctly after an Flmsg item was received, because Flmsg used a different character set. Flmsg 1.1.33 uses the UTF-8 character set, same as used for international language alphabets. Because of this, the VOA Spanish news item at the end of the show, after the Flmsg item, should display the correct diacritics.
Here is the lineup of modes for VOA Radiogram, number 30, 26-27 October 2013:
3:17 MFSK16: Program preview
7:02 MFSK16/32/64/128: Image in each mode
:45 MFSK32: Introduction to MFSK64L and 128L
1:43 MFSK64: VOA News re flying cars
2:00 MFSK64L*: Same VOA News story
2:16 MFSK32 image: Flying car in flight
1:20 MFSK128: VOA News re oldest comet strike
1:36 MFSK128L*: Same VOA News story
2:12 MFSK32/Flmsg**: News from kimandrewelliott.com
2:26 MFSK32: VOA News in Spanish re Blackberry
:33 MFSK32: Closing announcements
*Requires Fldigi 3.21.76AR. Note that text will not display until a few seconds after the tones are heard.
**Use Flmsg 1.1.33 to ensure that the accents appear correctly on the VOA Spanish news item that follows. To make Flmsg work with Fldigi, in Fldigi: Configure > Misc > NBEMS -- Under reception of flmsg files, check both boxes, and under that indicate where your flmsg.exe file (1.1.33) is located.
Please send your reception reports to firstname.lastname@example.org. Audio samples and screenshots are also appreciated.
Kim Andrew Elliott
Producer and Presenter