Tag Archives: Recordings

Recording Deutsche Welle Kigali’s final broadcast and remembering its early days

Kigali’s early days

Last week, SWLing Post reader Bob LaRose (W6ACU) sent me the following message and scans:

“Here’s some nostalgia from [when the Kigali relay] opened, 50 years ago!”

Bob then followed this with another email:

“I dug into the “vault” and I found [the] 1964 Third Quarter issue of “Hallo, Friends” from Deutsche Welle that talks about the “new” Kigali station as it was being built. The 1965 issues did not cover the actual inauguration.”

Click here to download this page as a PDF.

Many thanks for digging through your archives and sharing this wonderful DW nostalgia, Bob! It’s simply brilliant!

Readers: If you have shortwave nostalgia you would like to share on the SWLing Post, please contact me.

Shortwave Radio Recordings: Radio Poland

Catching a USAF HF-GCS transmission in Morocco

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My buddy, @K7al_L3afta (on Twitter), posted this interesting recording of the US Air Force High Frequency Global Communications System on 15,016 kHz USB at 18:01 UTC yesterday:

I don’t believe I’ve ever heard or noticed this type of USAF HF-GCS transmission before. Sounds almost like a numbers station.

Update: SWLing Post reader, Daniele, comments:

It’s an EAM, “Emergency Action Message”:

http://en.wikipedia.org/wiki/Emergency_Action_Message

http://mt-milcom.blogspot.it/p/what-is-emergency-action-message-or-eam.html

http://www.monitoringtimes.com/html/eam.html

Thanks, Daniele!

As I’ve mentioned before, @K7al_L3afta lives in an urban area of Morocco and his shortwave radio listening is plagued with radio interference (RFI). Still, he seems to snag some interesting catches on the shortwaves just like this one which he said he caught by “turning the tuning knob randomly.”

Serendipity is, indeed, the best type of SWLing!

You can follow @K7al_L3afta on Twitter by clicking here.

Shortwave Radio Recording: beHAVior Night via WBCQ

Pulling Radio Santa Cruz out of the interference

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I recorded Radio Santa Cruz early this morning around 05:00 UTC on 6,135 kHz using the TitanSDR I currently have under review.

Radio Santa Cruz‘s 10 kW signal from Santa Cruz, Bolivia, was very much audible here in North America, though RSC was competing with another station on-frequency at the time. Actually, Radio Santa Cruz was broadcasting slightly off-frequency–6134.8 kHz instead of 6,135 kHz. In this case, the fact that RSC was slightly below frequency helped me delineate the station’s audio from that of a competing station.

In the screen-grab of the narrowband channel from the Titan SDR (above–click to enlarge) you can see two distinct carriers spaced only .2 kHz apart (represented by the two peaks in the spectrum display and two parallel vertical lines in the waterfall display).

Here is what the audio sounds like in normal AM mode when we center on the Radio Santa Cruz frequency of 6,134.8 kHz:

You hear a hetrodyne and garbled noise from a competing station. Not pleasant audio.

If we change from the AM mode to eLSB mode (essentially, the TitanSDR’s version of synchronous detection on the lower sideband) we are ignoring all of the noise in the upper sideband, allowing the desired signal of RSC to pop out.

You can see in the screen-grab above that now only the lower sideband of the RSC signal is highlighted. Here’s a 21 minute recording:

Makes quite a difference!

It’s easy to see competing signals and interference on an SDR’s spectrum display, but if you hear something similar on your portable, try the techniques above to see if it clears up the signal.

If your receiver lacks a selectable synchronous detector, much of the same results can be gained by zero-beating (tuning in) the desired signal in lower sideband mode. Of course, if you have a receiver that lacks SSB mode, the best you can do is tune slightly below frequency in AM, in which case the results will not be as dramatic.

Conclusion? Listening in single-sideband or with a selectable sync detector might be all you need to dig a signal out of the interference.

Shortwave Radio Recordings: Voice of Nigeria

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For your listening pleasure: the Voice of Nigeria–recorded on January 28, 2015, starting at 10:00 UTC on 9,690 kHz.

The past few days, the signal out of Ikorodu has been much stronger than normal, so I’ve spent several afternoons listening to the wonderful sounds and music from the Voice of Nigeria.

Click here to download the recording as an MP3, or simply listen via the embedded player below: