VOA Radiogram, program 140, 5-6 December 2015, experimented with the transmission of QR codes as MFSK images and as UTF-8 block elements.

Here is the QR code as an MFSK32 image, received by Gough in Australia, about 14000 km from the North Carolina transmitter, 5 December during the 0930-1000 UTC transmission on 5865 kHz …

The same QR code transmitted as UTF-8 block elements in MFSK32 (120 wpm) was received much more clearly in Australia. It took advantage of the error correction included in MFSK32 text. …

The QR code transmitted as UTF-8 block elements in MFSK64 (240 wpm) did not survive the path to Australia …

But, from several locations in Europe and North America, there were many examples of the MFSK64 block elements decoding perfectly. For example, this one from Jeff in Texas (5 December, 1600-1630 UTC, 17580 kHz) …

Because of the uneven lines in the example above, the QR code does not decode successfully. It needs a monospace font, either in the Fldigi software, or in whatever text editor or word processor it is pasted to …

In the above example, even lines have been accomplished because of the monospace font. But the text editor shows thin horizontal white space between the lines, making the QR code difficult to decode. So the same QR code is pasted to plain old MS Notepad …

Notepad has a monospace font by default, and the horizontal white space is absent.

If you haven’t decoded the QR code yet, it’s the URL of the VOA Radiogram website …

voaradiogram.net

Bottom line, plain text is simpler and faster than the QR codes. But the QR code experiment was fun.