Many thanks to SWLing Post contributor, Bill Richards, who notes that Ozy Radio is now broadcasting on 4,835 kHz. Bill also shares the following recording:
Ozy Radio now on 4,835 kHz
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Category Archives: Recordings
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:
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.
Report from the 2017 Radio Preservation Task Force meeting
SWLing Post readers might recall that, last year, I had the distinctly great honor of presenting at the 2017 Radio Preservation Task Force meeting at the Library of Congress.
Several readers have asked me to share my experiences at the conference, so I’ll note the conference highlights here.
I attended all three days of the conference. The first day (Thursday, November 2) was held at the Woodrow Wilson Center and focused on Cold War broadcasting. It goes almost without saying that this was absolutely fascinating. I learned a great deal. One of the day’s recurrent discussion themes, for example, focused on the keen awareness of those inside the Iron Curtain that they had been regularly subjected to propaganda. In other words, the Cold War somehow created very discerning news listeners savvy enough to separate fact from fiction quite skillfully––an ability that many fear may (unfortunately) be eroding among today’s media audiences. 
That afternoon, SWLing Post reader, Phil Ewing, took me on an amazing tour of NPR’s new headquarters [thanks SO much, Phil!].
Later that afternoon at NPR, I attended an event celebrating NPR’s founding father and mission creator, Bill Siemering. Bill and I co-presented at the Winter SWL Fest in 2011, and I admire him greatly both as a journalist and as an individual; I particularly enjoyed the opportunity to be at this event held in his honor.
Friday and Saturday sessions were held at the Library of Congress and were equally riveting as they covered nearly every aspect of radio preservation.
Here’s our panel just a minute before the forum began.
I was on the Digital Curation panel along with Charles Hardy (West Chester University and National Council on Public History), Jonathan Hiam (New York Public Library), Matt Karush (George Mason University and Hearing the Americas), Elena Razlogova (Concordia University) and Mark Williams (Dartmouth College and Media Ecology Project).
The discussion was dynamic, and to my pleasure, our Radio Spectrum Archive was quite the hit. The sincere interest in this project was beyond encouraging. Indeed, after my presentation, I wasn’t able to address all of the questions from those in the audience because there were so many in line to speak to me about it; eventually the LOC had to re-arrange the room for a televised event, the 50th anniversary of the Public Broadcasting Act.
But there’s more. And it’s a great ending to our story, which is really only a beginning: via Alex Stinson with the Wikimedia Foundation, I was introduced to the Internet Archive team last month, whom, to our profound delight, has wholeheartedly agreed to support the Radio Spectrum Archive by giving us nearly unlimited space to store our massive collection of spectrum files.
In a word? This conference was brilliant. There simply couldn’t have been a better outcome for the Radio Spectrum Archive and I enjoyed every minute of it.
Many thanks to the entire RPTF team, especially Director, Josh Shepperd, for putting this spectacular event together.
I’ve been invited to a couple other archive conferences as a result of the RPTF meeting, and I’ll give these some consideration. Regardless, I know this: I’ll make room in my schedule for the next RPTF conference. No way am I missing it!
And at the next conference I look forward to speaking to each one of those people with whom tight scheduling prevented my speaking at this one. After all, it’s this kind of enthusiasm that assures the Radio Spectrum Archive’s future.
If you’d like a more in-depth report of the RPTF conference, check out this article in Radio World (via Richard Langley). If you’d like to learn more about the Radio Preservation Task Force, check out their website by clicking here.
Many thanks to my buddy, Bennett Kobb, who also gave me a tour of the brilliant LPFM station, WERA (96.7) in Arlington, VA–what an incredibly dynamic station and staff!
Ulysses E. Campbell (left) and Bennet Kobb (right) in the studios of WERA.
I’d also like to thank my friend Kim Elliott for generously hosting me during the multi-day event. Even modest accommodation in the DC area is very expensive–no doubt, Kim’s hospitality made the conference a reality for me. Thanks again, Kim!
Digging in the Noise: Weak Signal Audio Recovery with the AirSpy HF+ and Elad FDM-S2
I’m currently spending the better part of a week at Cape Lookout State Park on the Oregon coast, with a great view of the ocean through tall evergreen trees. This is one of my favorite parks in the Pacific Northwest, especially when DXing during the blustery winters from one of the nice cabins at Cape Lookout.
The view from the beach near my cabin; the turbulent waves were a precursor to the gale force winds at the park during the night of the 23rd!
Although I’m at the park for trans-Pacific medium wave DXing, I’m also comparing receivers, both SDRs and portables. This morning I sought out a few weak shortwave signals, pitting the Elad FDM-S2 SDR ($529 USD) against the AirSpy HF+ ($199 USD). I have a pair of the HF+ receivers to cover all of medium wave (as the FDM-S2 easily does). Many SWLing Post readers already know that the upstart HF+ trades bandwidth to gain high performance in order to keep the price reasonable.
My antenna used for the following recordings was a small “Flag” antenna using a Wellbrook Communications FLG100LN module and a 2K ohm variable potentiometer for termination. The design uses crossed tent poles in an “X” formation to support the wire loop. This design travels easily in a compact package; I have Dave Aichelman of Grants Pass, Oregon to thank for this very useful “tent pole loop” implementation of the Wellbrook FLG100LN.
The Wellbrook-based antenna functions superbly, and its low-noise design helps hold down QRM from the nearby cabins (which unfortunately have been “upgraded” recently with noisy cold fluorescent [CFL] light bulbs). The area around the Cape Lookout cabins used to be superbly low noise and suitable for radio listening, but now it is more of a challenge than before. The Wellbrook FLG100LN is perfect for the situation though; Wellbrook ALA1530LN Pro and ALA1530S+ 1-meter loop antennas work commendably at the park too.
The Wellbrook FLG100LN module with a home brew RFI choke in-line
A 2K ohm variable potentiometer is protected from the elements in a small plastic bag. The “pot” is adjusted for the best nulling of medium wave stations off the back side of the antenna’s reception pattern.
The “tent pole loop” antenna is strapped to a fence railing with ultra-strong Gorilla Tape to keep the 7-ft. square loop vertical.
On with the recordings…
For the FDM-S2 and HF+ comparisons I used the SDR-Console V3 software. Every parameter was identical for the receivers–sampling bandwidth, filter bandwidth, AGC, mode and so on.
Take a critical listen to the weak signals recorded with the SDR receivers, identified as only “Radio A” and “Radio B”. A link to a poll is at the end of this article; please indicate which recording of each pair has the most intelligible audio in your opinion, and submit your choices when you’ve made up your mind on each audio clip. After a week or so I’ll post the results of the voting, and identify the receivers.
9.615 MHz, LSB, Radio A
9.615 MHz, LSB, Radio B (note: the same male announcer heard in clip “A” begins at 00:14 in this “B” clip)
9.730 MHz, USB, Radio A
9.730 MHz, USB, Radio B
7.230 MHz, S-AM, Radio A
7.230 MHz, S-AM, Radio B
9.860 MHz, S-AM, Radio A
9.860 MHz, S-AM, Radio B
Note on 7.230 MHz recording: this was an interesting frequency, as the signal was tightly surrounded by a very strong local 40m ham radio LSB station as well as a strong China Radio International signal. There were other strong amateur and broadcast stations within 30-50 kHz of 7.230 MHz, also. This A-B test more than the others may indicate receiver performance in a strong RF environment on a crowded band.
Ready for the poll? Register your votes at the Google Docs form below:
In a week to 10 days I’ll post the results in another article. NOTE: I haven’t provided a “both sound the same” choice in the poll to encourage you to ‘dig deep’ into the audio and listen critically–to find something that stands out in one clip versus the other.
Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.
Radio Moscow: New Year’s Day, 40 years ago
Happy New Year SWLing Post community!
A few months ago, I published a post about Colin Anderton’s excellent Radio Moscow recordings from the late 1970s. Being a space flight enthusiast, all of Colin’s brief off-air recordings feature news from the 1977-1978 Soyuz 26 mission to the Salyut 6 space station.
Recently, I started posting Colin’s recordings on a schedule so that each recording is being published exactly 40 years from the original broadcast date. Check out the Shortwave Radio Audio Archive each day (or subscribe via iTunes) to listen to the recordings.
Below, I’ve embedded the recording from New Year’s Day 1978 where we learned that Yuri Romanenko and Georgi Grechko toasted the New Year with fruit juice (for obvious reasons, champagne was not allowed on the station!).