Shortwave listening and everything radio including reviews, broadcasting, ham radio, field operation, DXing, maker kits, travel, emergency gear, events, and more
Many thanks to SWLing Post contributor, Jim Meirose, who recently shared the following listener post:
Listener Post by Jim Meirose
My interest in radio started around 1960-61. My uncle was going to take a giant worn-out console Record Player/AM/FM/SW 1940s monstrosity to the dump. My father, who was an electrician and a general nut for all things electrical, stopped him, took the radio out before the console got trashed, put it in a makeshift cabinet, and showed me how to use it. That was how I got started.
A neat thing about the radio was it had one of those old “magic eye” tubes to aid in tuning. What could be cooler for a kid to play with? Plus, being able to hear all of what was to me just “weird stuff” on shortwave, was what got me hooked.
After a year or two I got the Heathkit GR-91 as a gift and my father helped me assemble it. We also put up a better antenna.
My Heathkit GR-91 and Q-mult I used starting in 1963, with a variety of antennas, up to 1971. (Stored in the cellar now, as you can see)
I spent several years and many many hours listening and logging and having fun with it. We were at or near the peak of the sunspot cycle then, so as you can imagine, it was amazing. That made it a pretty “hot” radio (although in that decade the high sunspots made most every radio “hot”) but it had one flaw that was really bad. The tuning dial was not even close to accurate. I even had it professionally aligned, in vain. You only had a ballpark idea of what frequency you were on.
The next problem with the GR-91 was that as you tuned up past around 14 MHz, a hum began and grew to where there was no point trying to listen at all for anything all the way up to 30 MHz. I gradually became most interested in 20 meter amateur radio listening.
I learned to tune SSB, helped by the fact that the set had a good BFO and great bandspread tuning. From about 1964 to 1968, I heard hams from over 250 ARRL countries. These were mostly on 20 meters, using a dipole. Then, I got drafted to the Army until 1970, came back, and listened again until about 1972. Then, life took over, and the radio was put away.
Around 2004, I started getting interested again. I got an old Hammarlund HQ-180, thinking to pick up where I left off in ’72, but gave up when I found the sunspot cycle was bottomed out. Plus, the old set was too complicated and difficult to use, and not in the best shape. So, again, radio was put aside.
Finally, early this year, having the time at last to do things right, after shopping around, I got the Kenwood R-600, put up a good antenna, and started in. Once I got in the groove again, I found the R-600 to be incredible. The reception is crystal-clear across all bands. Plus, lo and behold, with the digital dial I know EXACTLY what frequency I am on! And as far as DX, even with today’s low sunspots, I am hearing the whole world, better than in the 60s. Might not be “booming in” as they say, but still very cool. The key is to know when, where, and how to listen.
Lastly, besides the better technology of the radio, imagine the difference between now and the ‘60s, when there was no internet, no computers, and practically no reliable hard copy directories to be found. At least with ham radio listening, it was easy to ID what country was on, because of the standardized call sign prefixes. But, for broadcast stations, the only real way to identify the more “exotic” non-english language stations, was by listening, sometimes for hours, hoping to catch some recognizable station ID. More often than not, this would never come before the station went off-air, or faded out. Today, with online directories, that is not such a problem. But, imagine how, with my GR-91, being unable to provide exact frequency readings, that even the modern online directories would have been practically useless.
That’s it, there are the highlights of my shortwave experience from 1960 to today. Hope it was of interest.
The seller, who lives about 2 hours from my QTH, described his KX1 as the full package: a complete 3 band (40/30/20M) KX1 with all of the items needed to get on the air (save batteries) in a Pelican 1060 Micro Case.
The KX1 I owned in the past was a four bander (80/40/30/20M) and I already double checked to make sure Elecraft still had a few of their 80/30 module kits available (they do!). I do operate 80M in the field on occasion, but I really wanted the 80/30 module to get full use of the expanded HF receiver range which allows me to zero-beat broadcast stations and do a little SWLing while in the field.
The seller shipped the radio that same afternoon and I purchased it for $300 (plus shipping) based purely on his good word.
The KX1 package
I’ll admit, I was a bit nervous: I hadn’t asked all of the typical questions about dents/dings, if it smelled of cigarette smoke, and hadn’t even asked for photos. I just had a feeling it would all be good (but please, never follow my example here–I was drunk with excitement).
Here’s the photo I took after removing the Pelican case from the shipping box and opening it for the first time:
My jaw dropped.
The seller was right: everything I needed (and more!) was in the Pelican case with the KX1. Not only that, everything was labeled. An indication that the previous owner took pride in this little radio.
I don’t think the seller actually put this kit together. He bought it this way two years ago and I don’t think he ever even put it on the air based on his note to me. He sold the KX1 because he wasn’t using it.
I don’t know who the original owner was, but they did a fabulous job not only putting this field kit together, but also soldering/building the KX1. I hope the original owner reads this article sometime and steps forward.
You might note in the photo that there’s even a quick reference sheet, Morse Code reference sheet and QRP calling frequencies list attached to the Pelican’s lid inside. How clever!
I plan to replace the Morse Code sheet with a list of POTA and SOTA park/summit references and re-print the QRP calling frequencies sheet. But other than that, I’m leaving it all as-is. This might be the only time I’ve ever purchased a “package” transceiver and not modified it in some significant way.
Speaking of modifying: that 80/30 meter module? Glad I didn’t purchase one.
After putting the KX1 on a dummy load, I checked each band for output power. Band changes are made on the KX1 by pressing the “Band” button which cycles through the bands one-way. It started on 40 meters, then on to 30 meters, and 20 meters. All tested fine. Then I pressed the band button to return to 40 meters and the KX1 dived down to the 80 meter band!
Turns out, this is a four band KX1! Woo hoo! That saved me from having to purchase the $90 30/80M kit (although admittedly, I was looking forward to building it).
Photos
The only issue with the KX1 was that its paddles would only send “dit dah” from either side. I was able to fix this, though, by disassembling the paddles and fixing a short.
Although I’m currently in the process of testing the Icom IC-705, I’ve taken the KX1 along on a number of my park adventures and switched it out during band changes.
Indeed, my first two contacts were made using some nearly-depleted AA rechargeables on 30 meters: I worked a station in Iowa and one in Kansas with perhaps 1.5 watts of output power–not bad from North Carolina!
I’m super pleased to have the KX1 back in my field radio arsenal.
I name radios I plan to keep for the long-haul, so I dubbed this little KX1 “Ruby” after one of my favorite actresses, Barbara Stanwyck.
Look for Ruby and me on the air at a park or summit near you!
Many thanks to SWLing Post contributor, 13dka, who shares the following guest post:
Gone fishing…for DX: Reception enhancement at the seaside
by 13dka
In each of my few reviews I referred to “the dike” or “my happy place”, which is a tiny stretch of the 380 miles of dike protecting Germany’s North Sea coast. This is the place where I like to go for maximum listening pleasure and of course for testing radios. Everyone knows that close proximity to an ocean is good for radio reception…but why is that? Is there a way to quantify “good”?
Of course there is, this has been documented before, there is probably lots of literature about it and old papers like this one (click here to download PDF). A complete answer to the question has at least two parts:
1. Less QRM
It may be obvious, but civilization and therefore QRM sources at such a place extend to one hemisphere only, because the other one is covered with ocean for 100s, if not 1000s of miles. There are few places on the planet that offer such a lack of civilization in such a big area, while still being accessible, habitable and in range for pizza delivery. Unless you’re in the midst of a noisy tourist trap town, QRM will be low. Still, you may have to find a good spot away from all tourist attractions and industry for absolutely minimal QRM.
My dike listening post is far enough from the next small tourist trap town (in which I live) and also sufficiently far away from the few houses of the next tiny village and it’s located in an area that doesn’t have HV power lines (important for MW and LW reception!) or industrial areas, other small villages are miles away and miles apart, the next town is 20 km/12 miles away from there. In other words, man-made noise is just not an issue there.
That alone would be making shortwave reception as good as it gets and it gives me an opportunity to check out radios on my own terms: The only way to assess a radio’s properties and qualities without or beyond test equipment is under ideal conditions, particularly for everything that has to do with sensitivity. It’s already difficult without QRM (because natural noise (QRN) can easily be higher than the receiver’s sensitivity threshold too, depending on a number of factors), and even small amounts of QRM on top make that assessment increasingly impossible. This is particularly true for portables, which often can’t be fully isolated from local noise sources for a couple of reasons.
Yes, most modern radios are all very sensitive and equal to the degree that it doesn’t make a difference in 98% of all regular reception scenarios but my experience at the dike is that there are still differences, and the difference between my least sensitive and my most sensitive portable is not at all negligible, even more because they are not only receivers but the entire receiving system including the antenna. You won’t notice that difference in the middle of a city, but you may notice it in the woods.
When the radio gets boring, I can still have fun with the swing and the slide!
2. More signal
I always had a feeling that signals actually increase at the dike and that made me curious enough to actually test this by having a receiver tuned to some station in the car, then driving away from the dike and back. Until recently it didn’t come to me to document or even quantify this difference though. When I was once again googling for simple answers to the question what the reason might be, I stumbled upon this video: Callum (M0MCX) demonstrating the true reason for this in MMANA (an antenna modeling software) on his “DX Commander” channel:
https://www.youtube.com/watch?v=AYnQht-gi74
To summarize this, Callum explains how a pretty dramatic difference in ground conductivity near the sea (click here to download PDF) leads to an increase in antenna gain, or more precisely a decrease in ground return losses equaling more antenna gain. Of course I assumed that the salt water has something to do with but I had no idea how much: For example, average ground has a conductivity of 0.005 Siemens per meter, salt water is averaging at 5.0 S/m, that’s a factor of 1,000 (!) and that leads to roughly 10dB of gain. That’s right, whatever antenna you use at home in the backcountry would get a free 10dB gain increase by the sea, antennas with actual dBd or dBi gain have even more gain there.
That this has a nice impact on your transmitting signal should be obvious if you’re a ham, if not just imagine that you’d need a 10x more powerful amplifier or an array of wires or verticals or a full-size Yagi to get that kind of gain by directionality. But this is also great for reception: You may argue that 10dB is “only” little more than 1.5 S-units but 1.5 S-units at the bottom of the meter scale spans the entire range between “can’t hear a thing” and “fully copy”!
A practical test
It’s not that I don’t believe DX Commander’s assessment there but I just had to see it myself and find a way to share that with you. A difficulty was finding a station that has A) a stable signal but is B) not really local, C) on shortwave, D) always on air and E) propagation must be across water or at least along the coastline.
The army (or navy) to the rescue! After several days of observing STANAG stations for their variation in signal on different times of the day, I picked one on 4083 kHz (thanks to whoever pays taxes to keep that thing blasting the band day and night!). I don’t know where exactly (my KiwiSDR-assisted guess is the English channel region) that station is, but it’s always in the same narrow range of levels around S9 here at home, there’s usually the same little QSB on the signal, and the signals are the same day or night.
On top of that, I had a look at geological maps of my part of the country to find out how far I should drive into the backcountry to find conditions that are really different from the coast. Where I live, former sea ground and marsh land is forming a pretty wide strip of moist, fertile soil with above average conductivity, but approximately 20km/12mi to the east the ground changes to a composition typical for the terminal moraine inland formed in the ice age. So I picked a quiet place 25km east of my QTH to measure the level of that STANAG station and also to record the BBC on 198 kHz. Some source stated that the coastal enhancement effect can be observed within 10 lambda distance to the shoreline, that would be 730m for the 4 MHz STANAG station and 15km for the BBC, so 25km should suffice to rule out any residue enhancement from the seaside.
My car stereo has no S-meter (or a proper antenna, so reception is needlessly bad but this is good in this case) so all you get is the difference in audio. The car had the same orientation (nose pointing to the east) at both places. For the 4 MHz signal though (coincidence or not), the meter shows ~10dBm (or dBµV/EMF) more signal at the dike.
3. Effect on SNR
Remember, more signal alone does not equal better reception, what we’re looking for is a better signal-to-noise ratio (SNR). Now that we’ve established that the man-made noise should be as low as possible at “my” dike, the remaining question is: Does this signal enhancement have an effect on SNR as well? I mean, even if there is virtually no local QRM at my “happy place” – there is still natural noise (QRN) and wouldn’t that likely gain 10dB too?
Here are some hypotheses that may be subject of debate and some calculations way over my head (physics/math fans, please comment and help someone out who always got an F in math!). Sorry for all the gross oversimplifications:
Extremely lossy antennas
We know that pure reception antennas are often a bit different in that the general reciprocity rule has comparatively little meaning, many antennas designed for optimizing reception in specific situations would be terrible transmitting antennas. One quite extreme example, not meant to optimize anything but portability is the telescopic whip on shortwaves >10m. At the dike, those gain more signal too. When the QRN drops after sunset on higher frequencies, the extremely lossy whip might be an exception because the signal coming out of it is so small that it’s much closer to the receiver noise, so this friendly signal boost could lift very faint signals above the receiver noise more than the QRN, which in turn could mean a little increase in SNR, and as we know even a little increase in SNR can go a long way.
The BBC Radio 4 longwave recording is likely another example for this – the unusually weak signal is coming from a small and badly matched rubber antenna with abysmal performance on all frequency ranges including LW. The SNR is obviously increasing at the dike because the signal gets lifted more above the base noise of the receiving system, while the atmospheric noise component is likely still far below that threshold. Many deliberately lossy antenna design, such as flag/tennant, passive small aperture loops (like e.g. the YouLoop) or loop-on-ground antennas may benefit most from losses decreasing by 10dB.
Not so lossy antennas, polarization and elevation patterns
However, there is still more than a signal strength difference between “big” antennas and the whips at the dike: Not only at the sea, directionality will have an impact on QRN levels, a bidirectional antenna may already decrease QRN and hence increase SNR further, an unidirectional antenna even more, that’s one reason why proper Beverage antennas for example work wonders particularly on noisy low frequencies at night (but this is actually a bad example because Beverage antennas are said to work best on lossy ground).
Also, directional or not, the “ideal” ground will likely change the radiation pattern, namely the elevation angles, putting the “focus” of the antenna from near to far – or vice versa: As far as my research went, antennas with horizontal polarization are not ideal in this regard as they benefit much less from the “mirror effect” and a relatively low antenna height may be more disadvantageous for DX (but maybe good for NVIS/local ragchewing) than usual. Well, that explains why I never got particularly good results with horizontal dipoles at the dike!
Using a loop-on-ground antenna at a place without QRM may sound ridiculously out of place at first, but they are bidirectional and vertically polarized antennas, so the high ground conductivity theoretically flattens the take-off angle of the lobes, on top of that they are ~10dB less lossy at the dike, making even a LoG act more like something you’d string up as high as possible elsewhere. They are incredibly convenient, particularly on beaches where natural antenna supports may be non-existent and I found them working extremely well at the dike, now I think I know why. In particular the preamplified version I tried proved to be good enough to receive 4 continents on 20m and a 5th one on 40m – over the course of 4 hours on an evening when conditions were at best slightly above average. Though the really important point is that it increased the SNR further, despite the QRN still showing up on the little Belka’s meter when I connected the whip for comparison (alas not shown in the video).
The 5th continent is missing in this video because the signals from South Africa were not great anymore that late in the evening, but a recording exists.
Here’s a video I shot last year, comparing the same LoG with the whip on my Tecsun S-8800 on 25m (Radio Marti 11930 kHz):
At the same time, I recorded the station with the next decent (but more inland) KiwiSDR in my area:
Of course, these directionality vs noise mechanisms are basically the same on any soil. But compensating ground losses and getting flat elevation patterns may require great efforts, like extensive radial systems, buried meshes etc. and it’s pretty hard to cover enough area around the antenna (minimum 1/2 wavelength, ideally more!) to get optimum results on disadvantaged soils, while still never reaching the beach conditions. You may have to invest a lot of labor and/or money to overcome such geological hardships, while the beach gives you all that for free.
But there may be yet another contributing factor: The gain pattern is likely not symmetrical – signals (and QRN) coming from the land side will likely not benefit the same way from the enhancement, which tapers off quickly (10 wavelengths) on the land side of the dike and regular “cross-country” conditions take place in that direction, while salt water stretching far beyond the horizon is enhancing reception to the other side.
So my preliminary answer to that question would be: “Yes, under circumstances the shoreline signal increase and ground properties can improve SNR further, that improvement can be harvested easily with vertically polarized antennas”.
Would it be worthwhile driving 1000 miles to the next ocean beach… for SWLing?
Maybe not every week–? Seriously, it depends.
Sure, an ocean shoreline will generally help turning up the very best your radios and antennas can deliver, I think the only way to top this would be adding a sensible amount of elevation, a.k.a. cliff coasts.
If you’re interested in extreme DX or just in the technical performance aspect, if you want to experience what your stuff is capable of or if you don’t want to put a lot of effort into setting up antennas, you should definitely find a quiet place at the ocean, particularly if your options to get maximum performance are rather limited (space constraints, QRM, HOA restrictions, you name it) at home.
If you’re a BCL/program listener and more interested in the “content” than the way it came to you, if you’re generally happy with reception of your favorite programs or if you simply have some very well working setup at home, there’s likely not much the beach could offer you in terms of radio. But the seaside has much more to offer than fatter shortwaves of course.
From left to right: Starry sky capture with cellphone cam, nocticlucent clouds behind the dike, car with hot coffee inside and a shortwave portable suction-cupped to the side window – nights at the dike are usually cold but sometimes just beautiful. (Click to enlarge.)
However, getting away from the QRM means everything for a better SNR and best reception. In other words, if the next ocean is really a hassle to reach, it may be a better idea to just find a very quiet place nearby and maybe putting up some more substantial antenna than driving 1000 miles. But if you happen to plan on some seaside vacation, make absolutely sure you bring two radios (because it may break your heart if your only radio fails)!
A little update (2023):
Like I said, the +10dB signal boost works both ways and here’s a nice example that I thought should be here. This is W4SWV, literally standing with both feet in the Atlantic ocean at the South Carolina coastline, carrying a 25W backpack radio with a whip and talking to F6ARC in France on 17m – received at my side of the pond using my simple vertical 33’/10m monopole antenna at the dike:
This was recorded on July 4th, 2021 and does not provide a reference to demonstrate how good or bad this is of course, all you have is my word that getting such a solid and loud signal from a 25W station on the US East Coast was just outstanding (compared to a fair number of coastal QRP stations I copied at the dike over the years, or the average 100W inland stations).
Meanwhile I found out that I’m luckily not the only (or the first) person who tried to make some practical experiments to reassess the theories in recent times: Greg Lane (N4KGL) made measurements by transmitting a WSPR signal simultaneously off 2 locations, one near the shoreline and one more inland. Measuring the signals created in distant WSPR receivers, he got similar results. He made a presentation about it in 2020:
Many thanks to SWLing Post contributor, Pete Madtone, who writes:
I was coming home from my tai chi class in the local park yesterday and remembered this play that I watched a long time ago. Please tell me you don’t know it!
[In] the credits at the end it has another radio connection: the UK reggae DJ (BBC) David Rodigan. Great eh?
“Life changes dramatically for radio amateur Norman when he gets in touch with a round-the-world yachtsman who introduces him to a different life – and a taste of fame.”
Thanks, Pete! I was not at all familiar with this TV Movie, but I absolutely love the nostalgia factor!
Post readers: Anyone familiar with “C.Q.”–? Do you remember watching it when it was first broadcast in 1984? Please comment!
Since I mentioned it, here is a pic of the antenna showing its installation:
Click images to enlarge.
In the above image you can see the overall setup of the LLD, the modification I did, by adding additional wires to the end of the arms and also the Mini Whip location
The LLD served me well, from LW up to around 200MHz allowing me to listen to broadcasters, hams, aircraft communications, time signals and then more, and it’s definitely a keeper, but I wanted to give a try to the “Mini Whip” antenna, even if a lot of people discard it saying it’s a noisy antenna and not worth it; keep in mind the Utwente SDR uses it and it seems to work fine, so I had to give it a try !
Anyhow, after searching the internet for a suitable whip, I finally found this one:
I bought the antenna on Amazon, but it’s also available on eBay and while the price isn’t the lowest one, I chose it since it uses BNC connectors only (some models use a mix of UHF/BNC or the like). This one had a top wing nut allowing to connect an additional (optional) external whip (may be useful on lower bands) and, last but not least, its color; being gray, it is quite stealth, which may be useful for some people (not my case, luckily). So I went on and ordered the antenna, the delivery took about 10 days and the package contents were exactly as shown above. The supplied coax is thin (RG-174 I believe) and it would be a good idea replacing it with some runs of RG-58, but for the sake of the experiment, I used the original wire.
So, having the antenna, I looked around for informations about the correct installation for the “Mini Whip” and found that in most cases, the reported poor performances of the Mini Whip are due to people installing it the wrong way. For reference and information about how the whip works and about how to properly install it, please refer to the information from PA3FWM found here and here.
Now, if you can place the whip in a garden or yard, using a pole, the correct installation of the whip is the one shown in this pic:
If you carefully look at the image you will notice that the whip sits above the supporting (metallic) pole and that the ground of the connector is electrically connected to the pole (through the clamp). Plus, the pole is then grounded (at the bottom) and the coax (which has chokes) runs away from the metallic pole.
What does the above mean ? Well, the Mini Whip antenna needs a “counterpoise” (ground) to work, and installing it as above, instead of using the coax braid as its counterpoise, the Mini Whip will use the supporting pole, this helps a lot minimizing the noise and it’s one of the tricks for a proper setup, the other one is placing the whip as far away from the “noise cloud” of your home as possible. In my case, I choose the far end of the balcony–also since I had a nice support there, the image below shows the whip installation using a piece of PVC pipe I bought at a nearby home improvement store:
At first, I just installed the antenna without the ground wire and with the coax coming down vertically from the connector. When I compared the whip to my LLD, the results were discouraging: the noise floor was much higher and a lot of signals, which the LLD received without problems, totally disappeared inside the noise floor.
Being the kind of hard-headed guy I am (and having read the documentation about proper setup) I went on and made further modifications.
Let me detail the installation a bit better with this first image (click to enlarge):
As you can see in the above image, the whip is supported by a piece of PVC pipe which keeps it above the metal fencing of the balcony (or a support pole if you’ll use it) and I also connected a short run of insulated wire to the ground of BNC plug at the bottom of the whip. This short run goes to a wire clamp which allows it to connect to the “counterpoise” (ground) wire.
In my case, since the balcony was at 2nd floor, I didn’t have a way to give to the antenna a real ground, so I decided to run a length of wire (AWG #11) down the pipe and then along my balcony fencing (10m total). An alternative, which will also work for roof installations, would be using chicken wire (fencing). In such a case, you may lay as much chicken wire as you can on the floor/roof and connect the wire coming down from the whip ground to it. I haven’t that that (yet!) but I think it may further lower the noise and improve performances.
Notice that in the case of the Utwente Mini Whip, the antenna support pole is connected to metallic roofing so it has plenty of (virtual) ground.
Later on, I improved the setup by raising the antenna a bit more and routing the wire (almost) horizontally from the feedpoint to reduce coupling with the vertical “counterpoise” wire.
The image below shows the final setup:
While not visible in the above image, I also wrapped the coax wire in a loop at the point where it’s held by the fencing and added some snap-on chokes to the coax at the point where it enters the building.
With all the modifications in place, the antenna started performing as it was designed to. The noise floor is still a bit higher than the one of the LLD, but given that it’s an active antenna, that’s to be expected
To give you an idea of the signals and noise floor, here are a couple of images taken from the screen of my laptop while running SDRuno. The first one shows the waterfall for the 40m band
While the second one, below, shows the one for the 80m band:
At any rate, my usual way of testing antenna performance (and modifications effects), aside from some band scanning/listening, is to run an FT8 session for some hours (and optionally repeat it over some days) and then check the received spots.
In the case of the Mini Whip, after all the modification to the setup, I ran an FT8 session using JTDX for some hours and the images below show the received spots. The first image shows the whole map of the received stations:
While the second one below is a zoom into the European region to show the various spots picked up there; the different colors indicate the 20m (yellow), 40m (blue/violet) and 80m (violet) bands:
As you can see, the Mini Whip performed quite well despite the “not exactly good” propagation.
While some time ago I’d have discarded the Mini Whip as a “noise magnet”, as of today, with a proper installation, I think it’s a keeper. While it can’t be compared to bigger antennas, I believe it may be a viable antenna for space-constrained situations. The only thing it needs is a bit of care when setting it up to allow it to work as it has been designed to.
Brilliant job, Grayhat! Thank you so much for sharing your experience setting up the Mini Whip antenna. As you stated, so many SWLs dismiss the Mini Whip as “noisy”–but with a proper ground, it seems to perform rather well. The benchmark example of a Mini Whip’s performance must be the U Twente Web SDR.
Before I had even taken delivery of the new Icom IC-705 transceiver, a number of SWLing Post readers asked me to do a series of blind audio comparison tests like I’ve done in the past (click here for an example).
Last week, I published a series of five audio tests/surveys and asked for your vote and comments. The survey response far exceeded anything I would have anticipated.
We received a total of 931 survey entries/votes which only highlights how much you enjoy this sort of receiver test.
In this challenge, I didn’t even give you the luxury of knowing the other radios I used in each comparison, so let’s take a look…
The competition
Since the Icom IC-705 is essentially a tabletop SDR, I compared it with a couple dedicated PC-connected SDRs.
WinRadio Excalibur SDR
The WinRadio Excalibur
I consider the WinRadio Excalibur to be a benchmark sub $1000 HF, mediumwave, and longwave SDR.
It is still my staple receiver for making off-air audio and spectrum recordings, and is always hooked up to an antenna and ready to record.
In the tests where I employed the WinRadio Excalibur, I used its proprietary SDR application to directly make recordings. I used none of its advanced filters, AGC control, or synchronous detection.
I also consider the Airspy HF+ SDR to be one of the finest sub-$200 HF SDRs on the market.
The HF+ is a choice SDR for DXing. Mine has not been modified in any way to increase its performance or sensitivity.
In the test where I employed the HF+ I used Airspy’s own SDR application, SDR#, to directly make recordings. I used none of its advanced filters, AGC control, noise reduction, or synchronous detection.
I thought it might be fun to include it in a comparison although, in truth, it’s hardly fair to compare a $160 receiver with a $1300 SDR transceiver.
The Belka, to me, is like a Lowe HF-150 in a tiny, pocket package.
Elecraft KX3 QRP transceiver
The Elecraft KX3
The KX3 is one of the best transceivers I’ve ever owned. Mine has the CW roofing filter installed (only recently) and is, without a doubt, a benchmark performer.
If you check out Rob Sherwood’s receiver test data table which is sorted by third-order dynamic range narrow spaced, you’ll see that the KX3 is one of the top performers on the list even when compared with radios many times its price. Due to my recording limitations (see below) the KX3 was the only other transceiver used in this comparison.
Herein lies a HUGE caveat:
The WinRadio application
As I’ve stated in SDR reviews in the past, it is incredibly difficult comparing anything with PC-connected SDRs because they can be configured on such a granular level.
When making a blind audio test with a stand-alone SDR radio like the IC-705–which has less configurability–you’re forced to take one of at least two paths:
Tweak the PC-connected SDR until you believe you’ve found the best possible reception audio scenario and use that configuration as a point of comparison, or
Attempt to keep the configuration as basic as possible, setting filters widths, AGC to be comparable and turning off all other optional enhancements (like synchronous detection, noise reduction, and advanced audio filtering to name a few).
I chose the latter path in this comparison which essentially undermines our PC-connected SDRs. Although flawed, I chose this approach to keep the comparison as simple as possible.
While the IC-705 has way more filter and audio adjustments than legacy transceivers, it only has a tiny fraction of those available to PC-connected SDRs. Indeed, the HF+ SDR, for example, can actually be used by multiple SDR applications, all with their own DSP and feature sets.
In short: don’t be fooled into thinking this is an apples-to-apples comparison. It is, at best, a decent attempt at giving future IC-705 owners a chance to hear how it compares in real-word live signals.
Recordings
The Zoom H2N connected to my Elecraft KX2.
Another limiting factor is that I only have one stand-alone digital audio recorder: the Zoom H2N. [Although inspired by Matt’s multi-track comparison reviews, I plan to upgrade my gear soon.]
The IC-705 has built-in digital audio recording and this is what I used in each test.
The WinRadio Excalibur and Airspy HF+ also have native audio recording via their PC-based applications.
With only one stand-alone recorder, I wasn’t able to simultaneously compare the IC-705 with more than one other stand-alone receiver/transceiver at a time.
As I mentioned in each test, the audio levels were not consistent and required the listener to adjust their volume control. Since the IC-705, Excalibur, and HF+ all have native recording features, the audio levels were set by their software. I didn’t post-process them.
Blind Audio Survey Results
With all of those caveats and disclaimers out of the way, let’s take a look at the survey results.
Blind audio test #1: 40 meters SSB
In this first test we listened to the IC-705, WinRadio Excalibur, and Belka-DSP tuned to a weak 40 meter station in lower sideband (LSB) mode. Specifically, this was ham radio operator W3JPH activating Shikellamy State Park in Pennsylvania for the Parks On The Air program. I chose this test because it included a weak station calling CQ and both weak and strong stations replying. There are also adjacent signals which (in some recordings) bleed over into the audio.
Radio A: The Belka-DSP
Radio B: The WinRadio Excalibur
Radio C: The Icom IC-705
Survey Results
The Icom IC-705 was the clear choice here.
Based on your comments, those who chose the IC-705 felt that the weak signal audio was more intelligible and that signals “popped out” a bit more. Many noted, however, that the audio sounded “tinny.”
A number of you felt it was a toss-up between The IC-705 and the Belka-DSP. And those who chose the WinRadio Excalibur were adamant that is was the best choice.
The WinRadio audio was popping in the recording, but it was how the application recorded it natively, so I didn’t attempt to change it.
Test #2: 40 meters CW
In this second test we listened to the Icom IC-705 and the Elecraft KX3 tuned to a 40 meter CW station.
Radio A: Icom IC-705
Radio B: Elecraft KX3
Survey Results
The Elecraft KX3 was preferred by more than half of you.
Based on your comments, those who chose the KX3 felt the audio was clearer and signals had more “punch.” They felt the audio was easier on the ears as well, thus ideal for long contests.
Those who chose the IC-705, though, preferred the narrower sounding audio and felt the KX3 was too bass heavy.
Test #3: Shannon Volmet SSB
In this third test we listened to the Icom IC-705 and WinRadio Excalibur, tuned to Shannon Volmet on 8,957 kHz.
Radio A: WinRadio Excalibur
Radio B: Icom IC-705
Survey
The Icom-705 audio was preferred by a healthy margin. I believe, again, this was influenced by the audio pops heard in the WinRadio recording (based on your comments).
The IC-705 audio was very pleasant and smooth according to respondents and they felt the signal-to-noise ratio was better.
However, a number of comments noted that the female voice in the recording was actually stronger on the WinRadio Excalibur and more intelligible during moments of fading.
Test #4: Voice of Greece 9,420 kHz
In this fourth test we listen to the Icom IC-705, and the WinRadio Excalibur again, tuned to the Voice of Greece on 9,420 kHz.
Radio A: Icom IC-705
Radio B: WinRadio Excalibur
Survey
While the preference was for the IC-705’s audio (Radio A), this test was very interesting because those who chose the Excalibur had quite a strong preference for it, saying that it would be the best for DXing and had a more stable AGC response. In the end, 62.6% of 131 people felt the IC-705’s audio had slightly less background noise.
Test #5: Radio Exterior de España 9,690 kHz
In this fifth test we listened to the Icom IC-705, and AirSpy HF+, tuned to Radio Exterior de España on 9,690 kHz. I picked REE, in this case, because it is a blowtorch station and I could take advantage of the IC-705’s maximum AM filter width of 10 kHz.
Radio A: Icom IC-705
Radio B: Airspy HF+
Survey
The IC-705 was preferred by 79% of you in this test.
Again, very interesting comments, though. Those who preferred the IC-705 felt the audio simply sounded better and had “punch.” Those who preferred B felt it was more sensitive and could hear more nuances in the broadcaster voices.
So what’s the point of these blind audio tests?
Notice I never called any radio a “winner.”
The test here is flawed in that audio levels and EQ aren’t the same, the settings aren’t identical, and even the filters have slightly different shapes and characteristics.
In other words, these aren’t lab conditions.
I felt the most accurate comparison, in terms of performance, was the 40M CW test with the KX3 because both employed similar narrow filters and both, being QRP transceivers, are truly designed to perform well here.
I essentially crippled the WinRadio Excalibur and Airspy HF+ by turning off all all but the most basic filter and AGC settings. If I tweaked both of those SDRs for optimal performance and signal intelligibility, I’m positive they would have been the preferred choices (indeed, I might just do another blind audio test to prove my point here).
With that said, I think we can agree that the IC-705 has brilliant audio characteristics.
I’ve noticed this in the field as well. I’m incredibly pleased with the IC-705’s performance and versatility. I’ll be very interested to see how it soon rates among the other transceivers in Rob Sherwood’s test data.
The IC-705 can actually be tailored much further by adjusting filter shapes/skirts, employing twin passband tuning and even using its noise reduction feature.
If anything, my hope is that these blind audio tests give those who are considering the Icom IC-705 a good idea of how its audio and receiver performs in real-word listening conditions.
Radio Waves: Stories Making Waves in the World of Radio
Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’sRadio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!
Many thanks to SWLing Post contributors DM Barrett, Tracy Wood, Mike Terry, and the Southgate ARC for the following tips:
Tony Pavick combines love for music and radio in weekly show, Pop Shop Radio
While he may not be jumping up and down in a radio booth throwing records on turntables, Tony Pavick is once again pumping out radio in the form of a weekly hour-long show from his home in Hope.
It’s been 20 years since radio was broadcast from Hope – former radio personality and now fire chief Tom DeSorcy confirmed that CKGO, Hope’s AM radio station, closed its doors in 2000. And while Pavick isn’t starting a new radio station, he’s broadcasting for an hour each week from Hope to the world via shortwave radio.
Shortwave, a band in between the AM and FM band, Pavick explained, was utilized right up until the 1990s by countries wanting to spread their news, propaganda and cultural content. Living in the U.S., Pavick got his first taste of Canada while listening to Radio Canada International on a shortwave radio his parents bought him in the late 1960s.
Since the end of the Cold War, Pavick explains, countries have turned their radio equipment over to different groups. One of those is Channel 292 at the University of Twente, where he broadcasts at a rate of 15 Euro for an hour of radio time. Those without the ability to pick up shortwave can listen to Pavick’s show online at websdr.ewi.utwente.nl:8901/?tune=6070am.
The show starts with radio static, followed by the sound of a pop being opened and poured. Then Pavick comes in with “from the town of Hope in super natural British Columbia, in Canada, I’m Tony and this is Pop Shop Radio.”
Pavick plays a wide range of pop music, for example his first show included a Czech language version of Heart of Glass recorded when Czechoslovakia was still a nation, and a 2006 Groovefinder remix of Nina Simone’s Ain’t Got No.
He draws inspiration from a time when you could hear, on a top 40 station, a line-up featuring Jefferson Airplane, followed by Johnny Cash and then the The Beatles. “There was a great variety of music played on the same station,” he said. “Popular music wasn’t just rock n’ roll, it was rock and pop and country and just a whole variety of things. So that’s where the idea for it being called the Pop Shop came about.”
Pavick doesn’t keep it a secret where he finds some of the more obscure plays. He uses music website 45cat.com, an extensive online music archive.[…]
As the world’s second largest hamfest, we pride ourselves on delivering a high-quality event to our attendees and would not want to put on a show that is anything less than what the ham radio community deserves.
After much deliberation, the difficult decision to postpone the 75th Orlando HamCation was made. It is with heavy hearts that we must make this decision. We had wished to see all of you next year in person, but the situation we face globally has made this challenging. Instead, HamCation will be moved to February 11-13th, 2022. We are looking to host some unique Webinars, a QSO Party and possibly Prize Drawings for 2021.
More information to come on our website soon.
For those who have already purchased tickets and spaces, we will be in contact with you shortly and will reach out to you directly. You will have the option to use your ticket for HamCation 2022, receive a refund or donate the funds to the Orlando Amateur Radio Club.
We thank all of you for your patience and understanding during these times and are excited to see you all again in 2022…
73, Michael Cauley, W4MCA
General Chairman
Orlando HamCation
Gordon Bathgate can barely recall a time when he wasn’t in thrall to the radio and marvelling at all the different sounds which came out of a magic box in his living room when he was growing up in the north-east of Scotland.
A lot of snap, crackle and pop music has come and gone since these early days, but he is still Radio Ga Ga about an invention which has shaped all our lives and is celebrating its centenary in 2020.
This follows the innovation and imagination of so many pioneering figures, including his compatriot James Clerk Maxwell, Heinrich Hertz and Guglielmo Marconi, whose name has become inextricably linked with the device.
In so many different ways, Mr Bathgate, who has written a new book, Radio Broadcasting: A History of the Airwaves, has devoted decades to boosting its profile in many guises.
He was a founding member of Grampian Hospital Radio at Aberdeen Royal Infirmary – a service which does invaluable work and particularly in the current Covid-induced social isolation.
He also presented shows for North East Community Radio at Kintore and presents music programmes as far afield as Peterhead, The Netherlands and the fabled Radio Caroline.
He has created a series of witty little films, imparting his love for the Doric language, including pastiches of Star Trek and Dallas.
But it’s his passion for radio which shines through the pages of his new production.[…]
Many thanks to SWLing Post contributor, Jim Meirose, who recently shared the following listener post:
