The highly anticipated AirSpy HF+ Discovery SDR has been in the hands of early adopters for about two weeks–and I’ve seen nothing but positive comments!
After a long run (2007-2013) with a Microtelecom Perseus, my SDR of choice became the Elad FDM-S2, and more recently an Elad FDM-DUOr “hybrid” SDR receiver. The two Elads have the same core processing components and identical performance when the DUOr is connected via SDR software.
This week I’ve compared the HF+ Discovery ($169) against the FDM-DUOr ($899) using Studio 1 software and identical modes & settings. The following video features the radios’ performance on a crowded daytime medium wave band from suburban Seattle-Tacoma USA.
Mode, filter bandwidth, AGC, etc. are the same for each radio
768 kHz sampling bandwidth used for both receivers
Stations tuned are:
1320 KXRO Aberdeen WA, 74 miles @ 5 kW (in-line with antenna)
1110 Oak Harbor WA, 78 miles @ 500 watts (in antenna’s null)
1040 CKST Vancouver BC, 147 miles @ 50 kW (in antenna’s null)
1430 KBRC Mt. Vernon WA, 85 miles @ 5 kW (in antenna’s null)
750 KXTG Portland OR, 118 miles @ 50 kW (in antenna’s null)
I purposely sought out signals difficult to hear in the presence of powerhouse stations. Only 1320 kXRO (in-line with my antenna) and 750 KXTG are what you might consider average or fair quality signals. Headphones are recommended for most of these, particularly 1040 kHz.
You’ll note that the pass band has been “pulled” over the edge of the carrier frequency by a few hundred Hertz. This is an excellent trick that can often reduce noise and/or improve intelligibility. It’s a feature unique to Perseus, Studio 1, and SDRuno software; it works in sideband modes and in selectable sideband Sync AM (SAM) mode.
After listening to the signal comparisons, what are your thoughts on the HF+ Discovery? Please leave your comments below.
Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.
Thanks to a tip from SWLing Post contributor, Dan Robinson, I spent some air time with an old friend last night: Radio Educación broadcasting from Mexico City on 6,185 kHz.
Like a lot of small Central and South American shortwave stations, I believe XEPPM only broadcasts at 1,000 watts–though in the past, I believe they were allowed 10,000 watts. Still, their signal often makes it into eastern North America with relative ease, although it’s rare that it’s so clear. As summer approaches here in the northern hemisphere, QRN (noise from natural sources, like thunder storms) will rise on the 49 meter band. Even last night, there were some mild static crashes.
I tuned in around 01:25 UTC (April 1, 2019) with the WinRadio Excalibur and heard some amazing jazz, so I had to hit the record button.
For your listening pleasure, here’s the one hour ten minute recording I made:
Many thanks to SWLing Post and SRAA contributor, Richard Langley, who has recently uploaded an off-air recording of the Voice of Peace to the Shortwave Radio Audio Archive. This is a fascinating recording that I thought I would re-post here on the Post.
Live, off-air, approximately twenty-minute recording of the Voice of Peace from Baghdad on 29 December 1990 beginning at 21:40 UTC on a shortwave frequency of 11860 kHz. This broadcast originated from a transmitter either in Iraq or Kuwait.
Iraq’s Voice of Peace was established in August 1990 to beam programs to American servicemen stationed in Saudi Arabia during Operation Desert Shield following Iraq’s invasion of Kuwait at the beginning of the month. Programming consisted of music, initially easy-listening music but subsequently changing to a “Top 40” mix, news and commentary in a failed effort to try to demoralize the American troops. Beginning in September 1990, the broadcasts used a female announcer dubbed “Baghdad Betty” by the Americans. Reportedly, Baghdad Betty was replaced by a team of announcers sometime in December 1990. The recording is an example of the news and music programming. It is not known if the female announcer is the famous Baghdad Betty or someone else.
Reception of the broadcast was poor to fair with slight interference and fading. At 21:58 UTC, there is interference splash from WYFR starting up on 11855 kHz. The initial frequency recorded may have been 21675 kHz before switching after a minute or so to 11860 kHz as the radio teletype interference abruptly stops at this point. The recording includes frequent station identifications such as “You are tuned to the Voice of Peace from Baghdad.”
The broadcast was received in Hanwell, New Brunswick, Canada, using a Sony ICF-7600D receiver and supplied wire antenna draped around the listening room.
How would Christmas Eve at the Front have sounded on a radio back in 1943? Something like this…
Christmas Eve, 1943: America’s third in WWII.
On this day, exactly three-quarters of a century ago, America tuned into a special live broadcast that would not only engage American listeners, but also every major network in the US at the time: CBS, NBC, and Mutual Broadcasting Company. The simulcast program, “Christmas at the Home Front,” starred troop entertainment veterans Bob Hope and Bing Crosby, as well as numerous others including screen actor Lionel Barrymore–also well-known for his regular portrayal of the miserly Scrooge in NBC’s annual radio drama “A Christmas Carol”–and featured an address by then-President Franklin D. Roosevelt.
This broadcast also included live audio feeds from North Africa, Italy, New Guinea, Guadalcanal, New Caledonia, China, India, Panama, Alaska, Pearl Harbor and even Navy ships in undisclosed locations. Keep in mind, this was 1943. These audio feeds weren’t carried over the Internet or a satellite network, they were shortwave radio signals from remote sites–signals that were bounced off of the ionosphere and back to the studios where they were incorporated in a live radio show. No doubt, this holiday special required months of planning to orchestrate and perhaps even a leap of faith to execute.
Being something of a WWII radio buff, I’ve listened to this recording a few times in the past. And after receiving Bill’s message about it recently, I listened again; the audio obviously came from a recording at NBC studios, very pristine considering the recording’s age and the number of times it’s likely been copied or changed formats, but also with demarcated track switches, not exactly as it would have sounded on the air at the time.
Radio broadcast with entertainer Bob Hope, 1943. Source: Broadcasting and Recorded Sound Division, Library of Congress
So I did what any self-respecting radio geek would do: I fed the recording into an AM transmitter to recreate the sound as it might have played on American radios of the time, and made an off-air recording of the entire broadcast.
Hopefully now, with the help of this recording, you may be able to imagine what families on Christmas Eve in 1943, huddled around their radios, might have experienced as they strove to feel a little closer to loved ones serving in the war, while enjoying a little light entertainment and absorbing the latest message from their president.
But it’s also meaningful to note that times have certainly changed since 1943. Without a doubt, it’s often easy to be lulled into a nostalgic appreciation of that time, and former times generally, made all the rosier by the present knowledge that the outcome of the war was, in many respects, favorable to us. But those who know history know the truth: that war is hard, that our struggles both here and abroad were real, and that people died–as many as 85 million. When the drama was over, the fallen did not rise again to play in another film; they were gone, forever. This is the grim shadow that lies beneath the warmth of entertainment broadcasts like this one.
Fortunately, our civilization continues, and will always view the war and the political circumstances surrounding it through the fading glass of advancing time and hear it through the crackle of increasing distance. And fortunately, our then-enemies are now among our strongest allies. We have a diverse and international audience here at the SWLing Post, so I hope this recording is recognized for what it is: simply a moment in entertainment history that the passing of time allows us to enjoy, during a war the likes of which we hope never again casts such a shadow over us. One such was enough.
Now sit back, close your eyes, and set your time machine’s dial back to Christmas Eve, 1943…
Imagine you’ve just turned on the family console radio, the frequency dial gradually warming with its familiar glow, and have tuned to your local NBC station; soon, the voices of well-known entertainers begin to fill the parlor and the rest of the household, their tasks or play momentarily abandoned, quietly join you there to listen…
Many thanks to SWLing Post contributor, Tom Gavaras, who shares the following recording of Radio South Africa which was originally recorded on December 31, 1977 from his home in Plymouth, MN using a Hammarlund HQ-180.
During the late 1970s, Radio South Africa (RSA) would broadcast a New Years call-in show. This recording is from 1/1/1978 (12/31/1977 in the US). At two minutes into the recording, you can hear the interval signal for RAI (Italy) in the background. I have scoped (edited) the music. Unsure how long RSA carried on this tradition, but heard a similar call-in broadcast the following year on 1/1/1979.
Many thanks to SWLing Post contributor, Mark Pettifor, who writes:
One of the great things about DXing and SWLing is the variety of music one can hear. One of my favorite stations to listen to on shortwave for “exotic music” was Radio Tahiti, Papeete, French Polynesia, when they were still on shortwave.
If my memory serves me correctly, I believe something happened to the transmitter, and they never got back on SW. They were on mediumwave through December of 2016 (738 kHz); now they are on FM only. (Maybe us hobbyists should start a funding website to put them back on shortwave!)
Many a Saturday night I would turn on the DX-160 (my first SW rig) and let it warm up for a while, before tuning in 15170 to see how band conditions were. If the band was good, I’d get ready to record through the air. Once I started recording, I’d often leave the room and shut the door, because having three brothers around meant the possibilities were high for having “extraneous interference” on my recordings.
Saturday evenings were a good time to tune in, because of a music program that aired with a good selection of island music. The program had an announcer who spoke in the island vernacular (Tahitian?), and when that program ended they switched to French.
Here is a 30-min recording of Radio Tahiti on 15170 kHz from a while ago, most likely around one of the solar maxima of either 1980 or 1991. I’m leaning toward the 1980 cycle. My apologies for not being able to be more specific than that. I kept terrible records of my recordings. This would be recorded either with the DX-160 or a DX-302. Apologies too for the jump in volume at around the 2:37 mark.
So close your eyes, imagine you are lying in a hammock on a beach somewhere in the South Pacific, with a warm breeze off the ocean and your favorite cooled beverage nearby, listening to some of the best island music anywhere.
Many thanks to SWLing Post contributor, Dan Robinson, who discovered that the Bhutan Broadcasting Service was on the air Friday with an uncharacteristically strong signal into Europe. Dan made the following screencast of his reception using the University Twente WebSDR on August 31, 2018 on 6,035 kHz starting around 2024 UTC: