Category Archives: Recordings

Video: Moshe captures an echo in Radio Kuwait signal

Many thanks to SWLing Post contributor, Moshe Ze’ev Zaharia, who submits the following videos of his reception of Radio Kuwait at 10:30 UTC on April 6, 2018 from his home in Israel.

Moshe notes that the signal was of blowtorch strength and, for at least 45 minutes, there was an ever-present delay/echo. Moshe’s receiver is a (beautiful!) Zenith Trans-Oceanic T600 and his antenna a 15 meter wire:

Click here to view on YouTube.

Click here to view on YouTube.

Click here to view on YouTube.

Many thanks for sharing, Moshe!

Did anyone else note this echo? I wonder what happened at the Radio Kuwait transmitting station to make this happen?  Or, perhaps, it was a fault with the audio feed they received? Please comment!

Interval Signals + Radio Astronomy = Bliss

Yesterday, I spent part of the better part of the day at the Pisgah Astronomical Research Institute (PARI): a place that has begun to feel like a home away from home.

As you might imagine, radio astronomy observatories are places with very low levels of radio frequency interference. Since I had a few hours on the PARI campus to play radio, I used it as an opportunity to evaluate the CCRadio-EP Pro‘s AM/mediumwave performance.

For comparison purposes, I packed the CCRadio-EP Pro, Tecsun PL-660 and (for kicks) my Sony ICF-5500W.

Now isn’t the ICF-5500W a handsome boy?

I’ll post some of the CCRadio-EP Pro videos in my final review.

Though it was immense fun tuning through the AM broadcast band right through the gray line,  being an SWL, I eventually turned to the shortwaves. The only shortwave radio I had on hand was the amazing little Tecsun PL-660. Conditions weren’t as bad as I had expected–propagation was decent and did I mention no noise?

After tuning around a bit, I happened upon one of my favorite interval signals: that of the Voice of Turkey.

Everything around me–all that was on my mind–simply took a backseat to the simple pleasure of listening to an interval signal on a cool, foggy spring evening surrounded by the beauty of PARI’s campus and those giant radio telescopes.

Though the feeling was nearly impossible to capture, I did make a recording to share with SWLing Post friends and readers from around the world. I hope you enjoy:

Click here to watch on YouTube.

Treasure hunt: Seeking Somali radio recordings from 2010

Okay SWLing Post readers:  I need you to dig through your off-air recordings for something pretty obscure…

Over at the Shortwave Radio Audio Archive, I frequently receive inquiries from educators, researchers, historians, and enthusiasts looking for very specific off-air recordings, often for some worthy project or other.  It’s quite a thrill when I can lay hands on just what’s being sought in our rather deep recordings archive.

I recently received just such an inquiry from producer Meghan Keane at NPR, and though we were not able to provide immediate help, I’m quite intrigued by the subject and thus not quite ready to give up the search.  Meghan writes:

My name is Meghan Keane and I’m a producer for NPR’s Invisibilia. I’m working on a story about Somalia and music, and am currently looking for some archival sound.

Around 2010, many radio stations in Somalia broadcasted animal noises and gun shot noises to protest Al-Shabab. I am hoping to find audio of that to use in my story. Please let me know if you have any leads!

Fascinating stuff.  I do recall a news story about Somali radio broadcasts including animal and gun shot noises back in the day, but I never actually heard a broadcast on shortwave or mediumwave.

Post readers: Can you help Meghan track down such a recording? If you can, please comment and/or contact me!

Results: AirSpy HF+ vs Elad FDM-S2 Weak Signal Comparisions

Looking north toward Cape Lookout, Oregon, near the site of my SDR receiver recordings. Photo courtesy of Wikimedia Commons.
In my original article 10 days ago, I set up a SWLing Post reader poll to let you give your opinion on which shortwave recordings within four pairs of audio files provided the most intelligible result. The recordings were intentionally noisy, low-level signals to help us discover–through critical listening to the files–if there is a clear favorite between the AirSpy HF+ or the Elad FDM-S2 receivers. Of course, there were only four pairs of recordings…not a very large sample size.

However, 34 readers of the original article took the time to listen and respond, so let’s get to the numbers, shown in these graphs:

Interestingly, the responses above seem to point to:

  • Two recording pairs tied in the results (50% / 50%) or were very close (HF+ 52.9% / FDM-S2 47.1%)
  • The FDM-S2 led one recording pair by a large margin (67.6% / 32.4%)
  • The HF+ led another recording pair by an equally large margin (67.6% / 32.4%)

Taken as a whole, no obvious winner emerged, although one might conclude the HF+ has a slight edge due to its lead in the “very close” recording pair of 7.230 MHz.

One thing is clear–the AirSpy HF+ is a surprisingly good performer for its price of $199 USD! For many enthusiasts this will be all the SDR they need.

As a final note, I’ll mention that the AirSpy HF+ used for the tests was totally stock. I have not yet performed the “R3 Bypass” mod nor the firmware update to my HF+ units. The simple R3 Bypass, discussed at length on the AirSpy Groups.io forum, significantly boosts sensitivity of the HF+ from longwave up to about 15 MHz, without any noted overload issues. For more on this modification from a MW DXer’s perspective, read Bjarne Mjelde’s insightful article at his Arctic DX Blog.

Thank you to all the readers who took the time to listen to the SDR recordings in this comparision and register your opinions.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.