Many thanks to SWLing Post contributor, TomL, who shares the following guest post:
Summer Daytime DXing 2019
I took note of the mediocre band conditions this summer amongst amateur radio operators as they were making off the cuff comments about still being in a solar minimum. Some had gone out and bought upgraded transmitters to solve the problem (MOAR WATTS!). And more power thrown at a weak ionosphere does seem to help get a signal farther. I had not been out since the spring and decided to find out for myself. But instead of more watts, I wanted more height.
Greene Valley Scenic Overlook is open to the public from May through October on weekends only (and only from 11am-6pm). It was the largest land fill (aka, garbage dump) in Illinois, now covered over and producing captured methane gas. On August 3 & 4, I ventured over there to see if its 190 feet above the surroundings might help my radio reception.
After trying my luck with a 12 foot vertical antenna on a tripod (and numerous children running around it chasing butterflies or looking at the view of Chicago), I went out the next day and parked away from anyone and put up my 19 foot vertical on the roof of the car. This setup is still amazing to me and works much better than the tripod mounted antenna, probably because it has a proper ground plane as well as being 7 foot taller.
So, yes, the conditions were so-so, not too bad and not too good. Lots of weak signals and some empty frequencies that I had expected to hear some South American stations around the 5 – 10 kw range. Weak stations from Asia were more scratchy sounding than usual even with the extra 190 feet of height. Here are 5 broadcast recordings as a sample (times in UTC):
Running out of things to listen to, I wandered over to the 20 meter amateur radio band and found a different situation. Propagation was decent between the Western hemisphere and Europe. Lots of “pile ups” going on with people trying to make contact with their trans-Atlantic counterparts. Some said they were running 500 watts or more, so more power does seem to help! Here are 5 recordings to show how active it was:
This outing was quite educational and I find it curious that people running 1000 watts or less are able to be heard well between continents but the large broadcasters were difficult to hear. Antennas pointed in the right direction, at the right time of day and frequency, can certainly do amazing things, plucking those weak signals out of the air so easily. And I do think the extra height had something to do with hearing this magic, too!
An easy way to lookup amateur radio operator “call signs” is to go to web site QRZCQ.com which does not need a login. Some records may be out of date, but most of it is accurate.
Setup used was a cheap Dell laptop, Windows 10, SDR Console 3.03, connected to the AirSpy HF+, a Palstar amplified preselector, and an old Kiwa BCB filter, then going up to the car roof magnetic balun (a Palomar MLB2) which is then connected to the 4 magnet base and the MFJ 19 foot stainless steel antenna. You can read about it here:
Brilliant report, Tom! It’s true: the bands are fickle, but like you I always find interesting things to hear on HF. I think your setup using your vehicle as the ground plane for the antenna is a fantastic idea. Plus, set up is easy, self-supporting, and you’ll never have to worry about a park ranger, for example, complaining because you have a wire suspended from a tree. And when there are no trees? You’re still golden.
Thanks for sharing your experience and DX! Amazing that even with mediocre conditions, you still snagged some distant signals.
Many thanks to SWLing Post contributor, TomL, who writes:
Stumbled onto this article while on the RTL-SDR website. Talks about shielding noisy power supplies inside a homemade wire mesh cage. It might be interesting as a weekend project. I wonder if a noisy laptop could be put inside one of these things, too?
Many thanks to SWLing Post contributor, TomL, who shares the following guest post:
Stupid Radio Trick – DSP “Hi-Fi”
If you can remember the 1960’s, there was an audiophile rage going on called Hi-Fi. The base unit consisted of a ponderous piece of furniture consisting of a rectangular cabinet and equally large mellow sounding speaker of fairly smooth frequency response, say in the range of around 40 – 15000 Hz. They would have a built-in radio (using vacuum tubes) with large analog scale. Most would also have a “record player” embedded on the top to spin some vinyl discs (78 or 33 rpm).
For pedestrian consumers, it became a decision of how to keep up with the Joneses, so-to-speak. And that meant a trip to Sears to look at the latest offerings. When the decision finally came to purchase, of course no one could buy it outright. So, to add to the suspense, one had to put money down on “Lay-A-Way” plan that did not allow you to take possession of your prized choice until the last monthly payment! One had to visit or mail in a check every month.
So where am I going with all this? Well, as you can see from the photo [above], I have purchased three portable radios for three very different purposes. All three were painstakingly studied and reviewed and weighed against all other possible choices. All are highly rated by the usual reviewers like RadioJayallen, SWLing Blog readers and other internet personalities. The Sangean is for home use and listening to baseball games when I did not want to fire up the stereo hooked up to the Grundig Satellit 800. The small Sony ICF-19 is a phenomenal knock around radio for the car and listening while out to lunch or a walk in the park. The large Tecsun S-8800 is a possible replacement for my ailing 20+ year old Sony ICF-2010 for shortwave use.
Well, I was tired of listening to any one of them in terms of sound quality. The Sangean has too much upper bass/lower mid range, the small Sony is very carefully maximized for total speech clarity, and the Tecsun seems to lack a little in the mid range frequencies (compared to highs and lows). Staring at them, I thought to self, “What if I turn on the Sangean and Sony together???” What ensued was a revelatory sonic experience (it sounded pretty good)! One seemed to fill in the other in certain ways. But it was not perfect.
Duh, I had the new Tecsun in a carry case while trying to decide if I send it back for a tuning quirk and dug it out and plopped it on top. Turning it on, I heard more lows and highs, just like a Field Radio should have but with the mid range filled in! After very careful volume adjustment, I now have something that could rightly be called DSP Hi-Fi. At least, that is what I am calling it for now. ?
Violin and piano pop-out of an orchestra but not too harsh sounding. Rock & Roll sounds loud and punchy without that boombox effect. Bass lows are there (could be better, now all I need is a small subwoofer connected to the Tecsun line-out ???). Highs are there too but well controlled. Mid range voice clarity is stunning, as if someone is in the room with me but not sounding too forward! It is not room-filling but acts more like a near-field monitor. I like that I can line-up the speakers over each other.
The really fortunate thing is that all three radios have complete DSP for FM and receive my favorite over-the-horizon station with very similar reception quality. Also, they process DSP with a similar delay before output to its respective speaker. The sound is fairly coherent and even though it is still mono output, the full range of musical fidelity can be appreciated better. It is not audiophile quality but it is very satisfying and I can actually hear more details in the music than with any one of the radios by themselves. Just goes to show you that you CAN teach a new Radio dog old Tricks (LOL)!
I love it, Tom! Thanks for pointing out that sometimes it takes a “stupid radio trick” to really produce some amazing audio fidelity! This reminds me that in the early 90s, I used to have a Zenith Transoceanic and RadioShack DX-440 on my radio table in my room. If I recall correctly, the Zenith was on my left and the DX-440 on the right. I used to tune to shortwave, MW and FM stations and produce a makeshift “stereo” effect by playing both at the same time. Sometimes, on shortwave, it actually helped me discern voices in weak signal work!
Many thanks to SWLing Post contributor, TomL, who shares the following guest post as a his Backpack Shack 3 continues to evolve:
Backpack Shack 3.0 – Part 3
I have now gone overboard since I think bigger must be better. The temptation was just too great and now there is an MFJ-1979 17-foot telescoping whip antenna in my car (with consequences).
I have a love/hate relationship with MFJ products because of what I think are useful ideas that are made somewhat poorly. But I went ahead and bought the large whip since I figured they could not possibly screw up something so simple, right?
Wrong. As I excitedly tried to screw the supposed 3/8”-24 threaded end into the nice standard Firestik K-11 magnet mount, I realized I was turning and turning it but it was not going in!!! I even had a small steel sliver of metal sticking into my flesh to prove I was not dreaming. The previous day, it had screwed in very tightly, but it did screw in. So, there I was after a long day of work, ready to listen to some SWL-Nirvana and I could not get the blasted antenna into the mount–? That Firestik mount is a VERY standard 3/8”-24 female thread and the other third-party antenna shafts fit perfectly and easily EVERY time I use them. I hate $60 of poor workmanship and MFJ seems to be the poster child of overpromising and underdelivering.
I was determined to make this work, by force if needed. One of the Trucker antenna shafts by necessity had an extra coupling nut on it to allow the extra 18 inch shaft to connect, so I took it off there and tried to thread it onto the MFJ-1979. It barely moved. Not to be thwarted, I dug out an adjustable wrench and 3/8” socket wrench with ½” socket and grunted and twisted and tightened until the coupling nut was threaded all the way “up its shaft”. That is what I feel like telling MFJ! That coupling nut is never coming off and now that I truly have bought it and cannot return it, I might as well use it.
The stainless steel telescoping rod is extremely thin and feels like it can bend and dent with any kind of mishandling. So it resides collapsed in a 27 inch PVC pipe with plumbing pipe foam inside to baby it when it is not being used. It remains to be seen if I can remember to “Handle With Care” when extending/collapsing it. We’ll see.
OK, so using the 18 inch antenna shaft attached to the magnet mount, then the coupling nut on the MFJ antenna, I extended it to a total of about 13 feet. With the DX Engineering Pre-amp turned on, and using the SDR Play RSP2, I was getting many signals booming in. All the usual names we are familiar with – RMI, CRI, Turkey, Cuba, etc. But also the noise level was very high. I know it is summer but I may have been overloading the Pre-amp a little bit. Here is an example, Radio Progresso from Cuba with some very nice acapella music but also a noisy background (plus, a noisy laptop computer pulse!):
So I decided to come back in the morning before my workday started and see if the static crashes would have died down.
The next morning I had everything hooked up again in the same spot at the Forest Preserve (located in a suburb of Northern Illinois). I moved the Cross Country Preselector to be directly connected from the roof, then to the antenna switch on the “Breadboard” (see part 2) to better prevent overloading. I turned on the Verizon battery pack and nothing. No Pre-amp light. Switched it on, off, on, off – nothing. So, I thought I must have burnt it out the previous session?
Later on, I found it was some sort of short in the switch and I will have to move the D-cell batteries to a backup battery pack. In the meantime, I had to do without the Pre-amp and was forced to extend the MFJ antenna all the way. With the 18 inch extension attached to the magnet mount, that was a total of 18.5 feet from antenna tip to the top of my car roof.
This was actually fortuitous since I was already concerned about overloading the Pre-amp or perhaps amplifying background noise. This forced me to test it in a more “barefoot” manner, hearing what it would natively hear without any Pre-amp. It was also lucky there was no wind to blow it over! It seems that if one is in an RFI-quiet area with decent view of horizons, the 20+dB Pre-amp may not be needed, depending on frequency band involved.
I have read that “Norton” style 10 dB Pre-amps and custom handmade transformer baluns are used by Dr. Dallas Lankford in his Low Noise Vertical antennas. I don’t want to get into winding baluns so I am using one Palomar Longwire Balun to simulate the “magnetic” transfer. His design uses two, one 10:1 at the antenna and a 1:1 balun at the feedline into the house. For more reading on LNV antennas, see these references:
I purposely monitored Voice of Korea for their news statement on the De-Nuke talks on the 25 meter band and found it came in great, just as many others have heard it. This was encouraging. Examining carefully the Data file from the SDR, here is what I pulled from it. I am pleasantly surprised and happy with the results; some stations I had never heard before and the language and music are very exotic. All of it was a little more than one half hour of recording time (14 June 2018, 1300 UTC). You may have to crank up the volume on the weaker recordings to hear those properly.
Taiwan International, 11640 kHz, Chinese, Kouhu Taiwan (blasting in strongly plus strong echo of broadcast at top of the hour – is a second transmitter signal going around the earth the other way and getting to me??)
Eighteen feet of whippy rod can sway in the gentlest breeze (consequences of “bigger must be better”). The described setup has fallen over in as little as a 12 mph sustained wind when fully extended because I had the base in a plastic box. I want plastic under the magnet(s) in order to get it off easily and put away out of sight! Now installed is a larger QUAD magnet mount for better stability:
I am using the flat plastic lid from a 20 gallon tote container under the quad mount and a mover’s tie down strap to the main bar of the quad (I have room for multiple straps if needed). Ten foot fits just fine:
Because the backpack and quad mount can fit inside the 20 gallon tote container, this setup can be attached to a picnic table in a state park or campsite if I choose. The Firestik single magnet mount will be recycled as a VHF antenna mount. I can go virtually anywhere now.
Instead of the 20+dB DX Engineering Pre-amp, perhaps one of those “Norton” 10 dB Pre-amps might be optimal (Kiwaelectronics.com broadband-preamp). And I need to figure out why my Verizon battery pack failed as each Tenergy D cell measured fine. Oh yeah, I have to buy an extra coupling nut, too……
Thanks so much for sharing this latest iteration of the BackPack Shack 3.0, Tom! It seems to me, as you imply, your current setup could be installed pretty much anywhere.
I’m sorry to hear about your troubles with MFJ. I’ve only had good experiences with them in the past, but I suspect the specs on the 3/8”-24 thread were simply incorrect or perhaps metric and mislabeled.
Many thanks to SWLing Post contributor, TomL, who shares a recording he made of the Voice of Korea on June 14, 2018. This English broadcast focuses on the Singapore summit and is, no doubt, historic in its content. [Note that we’ve posted other recordings on the Shortwave Radio Audio Archive.]
Recorded on my noisy Lenovo laptop, SDRPlay RSP2, and an unamplified 18.5 foot antenna on the roof of my SUV.
I’m most impressed with the quality of his recording–VOK is not the easiest station to snag in the US midwest:
Thank you for sharing, Tom! I love your field portable vertical–obviously, it’s doing a fine job and your car must make for a decent ground plane!
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