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, Jack Dully, who writes:
Happy Holidays to Y’all!!! Thomas, I have bought about 5 antennas from the eBay seller”Lowbander” over the last few years. […]They are well constructed, strong and really bring in signals on the fringe. He has a small operation, I believe, but dedicated to making the best antennas he can. His antennas will last through storms and such but grab signals like a fly on honey, no kidding. Perhps other SWLing Post members don’t know of these excellent antennas at what I think is a good deal and worth the cost for years in the air. Thanks.
For the past few years we have been working on finding the best way to help beginners get started with L-band weather satellite reception and basic radio astronomy. We have now come up with a solution that we’re calling the ‘Discovery Dish’ – a lightweight 65 cm diameter dish and active filtered feed set.
Discovery Dish is a 65-cm diameter aluminum satellite dish and active filtered feed designed for receiving GOES HRIT, GK-2A LRIT, FengYun LRIT, NOAA HRPT, Metop HRPT, Meteor M2 HRPT and other weather satellites that operate around 1.69 GHz. The dish is designed to weigh under one kilogram, and it splits into three petals, making it easier to ship worldwide. The 1.69 GHz feed contains a built-in LNA right at the feed point, as well as filtering, which means that there is almost no noise figure loss from cables or connectors.
Note that the prototype images show an early non-petalized prototype with rough laser cut wind holes. The production version will obviously be a lot neater looking! […]
State-owned China Radio International is airing its content without attribution on commercial radio stations in Europe.
China has consistently and systematically pursued the dissemination of its narratives on the global stage, with the primary aim of shaping the international landscape to align with its strategic interests and ideological perspectives. These endeavors encompass a diverse array of tactics, including the acquisition of media enterprises, active engagement by Chinese ambassadors in both mainstream and fringe media outlets, the utilization of paid supplements, collaboration with pro-Kremlin media, and the steadily expanding presence of China across various social media platforms.
Recently, China Radio International (CRI), an official Chinese state media outlet broadcasting in multiple languages, has garnered attention for its establishment of partnerships with and provision of content to radio stations worldwide. Remarkably, CRI has effectively outsourced the production of China-related programming to local partners, often without transparently disclosing the sponsorship of content creation to the listeners. This strategy, known in Chinese as “borrowing a boat to go out on the ocean,” plays a pivotal role in laundering Beijing’s propaganda and fostering the acceptance of its messaging among local audiences.
One illustrative case of this approach within Europe involves two Czech radio stations, namely Radio HEY, a nationwide commercial radio station airing rock music, and Radio Color, which positions itself as “one of the last independent radios.” From 2019 to May 2023, these radio stations broadcasted a program titled “Barevný sv?t” (Colorful World), a nearly 30-minute segment aired six times a week, with the objective of acquainting Czech listeners with Chinese culture, language, and history. [Continue reading…]
When cheap digital TV dongles enabled radio enthusiasts to set up software defined radio (SDR) systems at almost zero cost, it caused a revolution in the amateur radio world: now anyone could tune in to any frequency, with any modulation type, by just pointing and clicking in a computer program. While this undoubtably made exploring the radio waves much more accessible, we can imagine that some people miss the feeling of manipulating physical buttons on a radio while hunting for that one faint signal in a sea of noise. If you’re one of those people, you’re in luck: [Kaushlesh C.] has built a portable, self-contained SDR system with real knobs and switches, called SDR Dock 1.0.
The heart of the system is a Raspberry Pi running GQRX, an open-source SDR program that supports many different RF modules. [Kaushlesh] used an Airspy HF+ Discovery, a compact receiver that can work the HF and VHF bands, but it’s easy to modify the SDR Dock to accept other types like those ubiquitous RTL dongles. A seven-inch LCD screen with integrated speakers forms the main output device, with everything powered by a 10,000 mAh lithium-polymer battery. [Continue reading…]
Many thanks to SWLing Post contributor, Martin Tobisch, who shares the following guest post and videos from his home in Malta:
New AM Signal Coupler
Many AM medium wave listeners are looking for solutions to improve the reception performance of their radios.
After many attempts, which I don’t want to entertain anyone with, a coupler was created that feeds the external antenna directly into the ferrite antenna. I use my 66 foot long wire antenna on 50 ohm RG-58 cable, but other antennas will have similar success.
The clips available on YouTube speak for themselves:
https://youtu.be/FIylJk3F9Xk?si=Kp7SowdUXI5i5QAV
https://youtu.be/RHAla9jPoi8?si=VoG3w274k08Ul8Q4
Experiments with smaller ferrites and antenna rods met with no success. It is important that the coupler still works even at a distance from the ferrite antenna and without precise alignment.
With tube radios it easily bridges the distance from the housing to the ferrite rod Antenna
The finished coupler consists of 6 NiZn ferrite cores, which are connected with glue to form a rod. 8 turns of wire are wound over this and soldered to an RG-58 cable. Some electrical isolation tape and ready. So far I’ve just put it in a box. Of course there are finer solutions and it should be protected against shock. Ferrite cores are notoriously brittle.
Advantages: Advantages to what? Nothing comparable exists.
So there are advantages to feeding via an antenna socket. The signal coupler is also good for radios without an antenna socket. But in case of using an antenna socket, common mode wave interference picked up in the house goes unlimited into the radio. Due to the magnetic coupling to the ferrite antenna, common mode waves are completely suppressed. They do not create a magnetic field in the coupler.
No changes are necessary in the radio
The biggest advantage is, that you can listen to distant stations loud and clear, which previously only produced a quiet scratching noise.
Many thanks to SWLing Post contributor, Zach R., who shares the following guest post:
A review of the outdoor Planespotter antenna prototype
When it comes to airband monitoring, the stock whip antennas that ship with desktop and portable scanners are not the greatest. They’re fine if you’re at an airport and only interested in communications specific to your immediate area, but if you are someone like me who lives well out from any major airport, quality listening in can be impossible without some help in the antenna department.
Ideally, you want something like a discone or similar for omnidirectional listening, mounted as high as possible. This is not always possible or practical, however. SWLing Post contributor Ron recently reviewed the indoor Planespotter antenna, and I have one as well that works better than any rubber ducky, and can be easily hidden away when company comes.
Recently, the creator has come out with a prototype outdoor model. It’s the same design as the indoor unit, but with a longer run (25 feet) of coax, terminating in a BNC connector.
Besides the longer cable, the only other obvious change is the antenna is house in a skinnier PVC tube from the indoor model. It’s also sealed at the bottom so moisture won’t get in.
It has the same small metal hook on top, suitable from hanging from various mounts. I’d like more mounting options, but the hook does make for quick installation and removal. The half-wave length isn’t ungainly to handle and if painted it could easily be mounted on the side of a home without many people noticing.
The indoor version definitely works best on the VHF air band and seems to roll off aggressively above and below that band. The outdoor version, in side-by-side tests, seemed to perform the same on the air band but notably better on the VHF public safety band. It also pulled in more UHF air band traffic than the indoor model, despite being basically the same design.
The new outdoor version is a good choice for someone looking for a simple, already assembled antenna that’s suitable for temporary use or stealth mounting.
Disclosure: The outdoor prototype was supplied to me for free in exchange for a review. While taking more photos of the antenna I noticed the weatherproofing had come undone from the bottom. Hopefully this issue can be addressed before the antenna goes into production.
Many thanks to SWLing Post contributor, Bill Hemphill, who shares the following guest post:
Remote Antenna Switching Remote Low Noise Amplifier Switching and Switching an Antenna and Audio Between Two Radios
by Bill Hemphill, WD9EQD
Remote Antenna Switching
I have two YouLoop Antennas. I had been placing them at right angles to each other. I would then put one of them on the AirSpy software defined radio. But manually switching from one antenna to the other was a real pain. If only there were a way to electrically switch between the two antennas.
It would be nice to place the antennas remotely from the radio (and computers) and then have some sort of remote switch that would select an antenna and then a single feed line to the radio. It was research time.
The YouLoop and the Airspy both use SMA connectors. An SMA switch would be required. A little research and I came across the following small board that can switch between two SMA antennas:
This board is perfect for RECEIVE only projects. Apply 5V to the board and then 5V to the VCC (control pin) to switch from RF1 to RF2.
Now that I had the SMA switch module, a way to actually do the switch remotely was required. Maybe WI-Fi or Bluetooth module would do the trick. I found a nice Wi-Fi module on Amazon that looked like it would do the trick:
BIngo!! I could just press a button and switch antennas. But a problem quickly arose. I hadn’t fully read the description of the RODOT switch:
The blue output wire is ALWAYS Vcc (input voltage)! The device only switches the ground.
So the RODOT switches the ground but the HMC349 uses positive voltage to switch. OOPS. Next step was to place a latching relay to take the on/off ground and convert it to on/off positive. Again, another nice board was found:
The nice thing about the Relay Module is that it can be latched either High or Low, so the RODOT switching ground can be used to latch the relay and then provide a positive voltage to the HMC349 antenna switch.
All modules are powered by 5V. There are other modules available that use higher voltages. But I wanted to be able to use a 5V power source for everything.
I learned a quick lesson on the first layout I did. I had directly connected the antenna cables to the HMC349 module. A quick accidental side yank on one of the antenna cables and the SMA connector tore off the board. A replacement board and some quick wiring and I had a workable antenna switch that with the press of the car fob button, either antenna could be selected.
I found a nice small plastic box that allowed for the HMC349 module to be suspended between SMA bulkhead connectors. By using bulkhead connectors, there is no strain placed on the HMC349 connectors. The relay module was attached to the box lid. The modules are mounted using brass standoffs. The finished box is about 3”x4”x 2” high. Either battery or a 5V wall module can be used to power it.
Overall, I’m quite pleased with the results. I find that sometimes switching antennas (and their orientation) can make a big improvement in the signals. Other times, there’s very little difference.
Remote Low Noise Amplifier along with Antenna Switching
Now that the antennas can be switched, it would be nice if a Low Noise Amplifier could be switched in and out of the circuit. Something like the Lana HF Barebones LNA made by NooElec:
For testing purposes, I first did a quick layout of just using one antenna with the ability to switch the LNA in and out. Note: I took a gamble on hooking the antenna cables directly to the HMC349 modules. Luckily, the SMA connects didn’t tear off the boards.
Two HMC349 modules are used. The first module selects the bypass or the LNA. Likewise, the second module also selects either the bypass or LNA. Note that the second module is turned upside down so that the switches match up when activated. Two modules were used so that the LNA is totally switched out of the circuit. Continue reading →
Many thanks to SWLing Post contributor, Ron, who writes:
If you like monitoring the VHF airband then this antenna might interest you.It is a half-wave dipole cut for the middle of the band. (Recall that half wave vertical dipoles do not need ground radials.)
It is very well built and pretty rugged but is not meant for outdoor use.
How well does it perform? That depends on several things…how far you are from your airport? What is the “lay of the land” where you live? Etc.
Does it work better than the supplied telescoping antenna that came with your scanner?
Yes indeed.
And you will also notice an improvement in comms from aircraft in flight, too.
I had hoped to hear the ATIS and VOR from my local airport but they are too far away (20 miles).
In addition, the eBay seller (and builder) is also very pleasant to deal with.
DW is now broadcasting a 30-minute daily Arabic-language radio program entitled “Sudan Now” on shortwave, Hotbird and SES-5 satellites and via the DW Arabic website.
As an unbiased radio program, “Sudan Now” will provide listeners in the target region with unbiased coverage of current issues in the region and will promote political, social and cultural dialogue through interviews, talk shows and reports.
Given the lack of independent information sources in Sudan and the limited ability of established media to broadcast due to internet outages and ongoing fighting, “Sudan Now” was specifically designed to be broadcast on shortwave and via the Hotbird- and SES-5 satellites. The satellite broadcast enables listeners in the target region to receive the program via their TV sets.
DW Managing Director Programming Dr. Nadja Scholz: “The conflict in Sudan is ongoing and has far-reaching effects on the entire region. It is absolutely necessary to provide the people there with a dedicated program that enables them to access independent, current and in-depth information. With shortwave radio, we further increase our ability to reach as many people as possible.”
Manuela Kasper-Claridge, DW editor-in-chief, said: “The humanitarian situation in Sudan remains catastrophic. There is a lack of everything – including free, independent information. This Arabic-language radio program is therefore urgently needed.”
The program broadcast will begin on Monday, June 26, 2023. It will air daily from Monday to Friday at 2:30 pm (local time, GMT+2) for a duration of thirty minutes. A repeat of the radio program will air daily at 8:30 pm.
“Sudan Now” can be heard in the afternoon on shortwave 15275 kHz/17800 kHz and in the evening on shortwave 15275 kHz/17840 kHz.
In addition, all broadcasts will be available on the DW Arabic website.
[…]Radio Ink: When Justin Sasso briefly mentioned KLMR’s story at Hispanic Radio Conference, it piqued the room’s interest. That’s a powerful AM story. How did this come to pass with you both?
Dan: So about a year ago in late July, KLMR was blown off the air from a micro-downburst. The previous owners couldn’t fix it and they were in danger of losing the license. When I saw the building, half the roof was gone and the antenna was dangling in the wind.
I’ve been in the radio business in Colorado for 40 years, with the last 20 in Colorado Springs, but I’ve never owned a radio station. And so when this opportunity came about, I reached out to Kirk. We had talked about possibly buying a company in Lamar previously. He’s not just the mayor, he’s my brother-in-law, but it was great that the mayor wanted to get involved in it too. So we’re off and running.
Radio Ink: For a mayor to step up and say, “This AM station is so important to my community that if nobody else will save it, I will,” is a huge testament to AM radio’s power and value.
Kirk: It’s vital. That’s what I had mentioned to Justin in that meeting about AM. When we look at rural Colorado and the ag market there, there’s a necessity for that. [Continue reading…]
The number of satellites whizzing by over our heads at any moment is staggering, and growing at a rapid rate as new constellations are launched. But sometimes it’s the old birds that are the most interesting, as is the case with some obsolete but still functional military communications satellites, which thanks to a lack of forethought are largely unsecured and easily exploitable. And all that’s needed to snoop in on them is a cheap ham radio and something like this simple and portable satcom antenna.
As proof of the global nature of the radio hobby, the design in the video below by Brit [Tech Minds] borrows heavily from previous work by Italian ham [Ivo Brugnera (I6IBE)], which itself was adapted to use 3D-printed parts in a German blog post a few years ago. [Continue reading…]
Many thanks to SWLing Post contributor, Jack Dully, who writes:
