Last weekend, Shortwave Radiogram included a brief "hidden message" during the
closing music. It was in the BPSK63F mode, centered on 50 Hz. At that very low
audio frequency, it was not audible. I did not publicize this message last week,
because I was not sure that data at such a low audio frequency would actually be
pass through the WINB and WRMI transmitters. When I established that the data
was transmitted by both stations, I publicized it in the @SWRadiogram Twitter
account. A few listeners were able to decode the BPSK63F. The BPSK63F is not as
robust as the MFSK modes we usually use, so it did sometimes fail during fades.
But it could work on a local AM (medium wave) station, where fading is not
generally an issue, coexisting inaudibly with the voice and music programming.
We'll try this again in future shows.
Thanks to those of you who stated
your preference on the line breaks at 65 characters. There is now definitely a
consensus in favor of the 65-character breaks rather than "natural" line
wrapping.
This weekend's show is in the usual
MFSK32 and MFSK64. with nine MFSK images.
Here is the lineup for
Shortwave Radiogram, program 112, 8-11 August 2019, in MFSK modes as
noted:
1:47
MFSK32: Program preview 2:57 Czech restaurant's 50-crown fine for not
clearing plate 6:34 MFSK64: Radio waves from dead planets* 10:40 How
the 5 riskiest U.S. cities are preparing for floods* 15:23 This week's
images* 27:18 MFSK32: Closing announcements
* with
image(s)
Please send reception reports to
radiogram@verizon.net
And visit http://swradiogram.net
Twitter:
@SWRadiogram or https://twitter.com/swradiogram (visit during the
weekend to see listeners' results)
Facebook group: https://www.facebook.com/groups/567099476753304
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