Category Archives: Guest Posts

Guest Post: Crystal Radios – Construction, Listening, and Contesting

Many thanks to SWLing Post contributor, David Day (N1DAY), for sharing the following guest post:

Crystal Radios – Construction, Listening, and Contesting

By David Day – N1DAY

The date was November 2, 1920 and the world was about to change forever when radio station KDKA out of Pittsburgh PA made its first broadcast of election results from the 1920 presidential election. For the first time in history people knew who won the election before reading about it the next day in the newspaper. Radio had arrived!

However, hearing the election results was not as easy as powering up an AM radio receiver because radio electron tubes had only been invented a few years earlier and they were still too expensive for most people to afford in a radio set. After KDKA’s historic broadcast, large 50,000 watt stations began popping up in all major cities around the world. Even though a tube-driven radio was not yet commonplace, many people listened to these stations on their crystal radios. The frenzy around radio in the 1920’s was not unlike the excitement around cell phones and the internet today. If you didn’t have one, you were simply living in the past.

A family listening to a crystal radio in the 1920’s

Fortunately, in the early 1920’s the crystal radio had been around for a while and it was easy to make or purchase a completed set on a limited budget. The beauty of the radio was that it was a passive device needing no power source other than the radio station’s broadcast that was received by a good antenna about 50 feet long and 15 or so feet above the ground. Crystal radios derived their name from use of galena crystals as detectors. Continue reading →

Shortwave’s Giant: Carlos explores evangelical broadcasting to MENA

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Many thanks to SWLing Post contributor and political cartoonist, Carlos Latuff, who shares the following guest post:

WINNING HEARTS, MINDS AND…SOULS!

Catechizing via shortwave.

by Carlos Latuff, special for The SWLing Post

During the Vietnam War (1955-1975), the expression “hearts and minds” became popular and referred to the US government’s strategy to gain allies among the South Vietnamese against the Vietcong guerrillas. Over the years this strategy has been used in different contexts. What I’m going to talk about in this short article is how the radio waves have served Christian evangelical churches, to win hearts and minds, specially in Africa and Middle East (MENA).

Different from what I did with the Ethiopian clandestine broadcasts, when I spent around 3 months monitoring, with evangelical radios it took only two days in January 2022; quite simple, since they’re stations with regular programming. Most of them have good signal reception, there’s no jamming from other countries and, despite transmitting in different languages, little translation was necessary since the content is always the same: religious preaching.

All listenings happened in Rio de Janeiro. The radio sets used in this monitoring were the XHDATA D-808 and an old analog radio Sanyo RP-8351, made in Brazil in the 70’s. A 7-meter long wire antenna was used in all listenings. Continue reading →

Guest Post: Following the Ethiopian war over shortwave radio

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Many thanks to SWLing Post contributor and political cartoonist, Carlos Latuff, who shares the following guest post:

Carlos Latuff at Catacumba Park in Rio de Janeiro, monitoring Ethiopian broadcasts.

ETHIOPIA: A WAR THROUGH RADIO

by Carlos Latuff, special for The SWLing Post

We just entered 2022 and the civil war in Ethiopia has already completed 1 year. On the one hand we have the Tigray People’s Liberation Front (TPLF) guerrillas from northern Ethiopia and its allies, and on the other hand we have the armed forces of Ethiopian government and its allies. The dead are piling up, accusations of war crimes from both sides, local and international political interests at stake, and no perspective for a peaceful solution. Without going into the reasons for this new war in Ethiopian territory, I’d like to focus on the use of radio waves by both parties of this conflict.

I monitored shortwave broadcasts from Ethiopia and to Ethiopia between October 21, 2021 and January 4, 2022. The receivers were Tecsun PL-606 and XHDATA D-808, using both the telescopic antenna and a long wire. In all cases, listening was carried out in Brazilian cities.

Carlos at Catacumba Park monitoring and recording clandestine Ethiopian broadcasts.

The monitored stations were: Continue reading →

The Gift That Keeps On Giving: Pavel’s Amazing Upcycled Hombrew Radios!

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Many thanks to SWLing Post contributor, Pavel Kraus, who shares the following guest post:

Inspiration for gifts

by Pavel Kraus

This article should be just an inspiration for how to make a gift for our wives and neighbors so that they are not upset that we are still sitting at the radio, but rather they also have something to do with it.

When I see a nice box, I get the thought of building a radio in it.

Iomega ZIP Drive Radio

For the production of the first two radios, I used boxes from Iomega ZIP floppy disk drives, which were previously widely used in DTP studios before the advent of USB flash drives and can certainly be found as discarded in warehouses.

Used electronic components can be purchased on eBay, Amazon, Aliexpress – they are radio modules, batteries, charging module, other components can be found in our amateur stocks.

After removing the inside of the Iomega ZIP drive, there is room for the module to be built in and the transparent window prompts you to place the module with the display.

I desoldered the encoders from the motherboard and placed them on the side of the radio. The fingerboard of the button from the drive can also be used as a power switch.

At the same time, the original LEDs can be used as an indication of charging the built-in battery.

In the second type of radio using the same box, a button control module is used, where the buttons have been desoldered and connected to a separate board inside the radio.

Russian Enclosure Radio

The third type of radio uses a box from Russian radio by wire, where an AM / FM radio module with a clock was built in.

Commodor C 64 Power Supply Radio

The last type uses half of the box from the Commodor C 64 power supply. It has a built-in radio module with IO SI 4732 (radio from the Commodore C64 power supply box with SI4732 radio module .jpg).

A photo of my wife is printed on the radio panel so she doesn’t say I’m looking at foreign women.

I wish you all a beautiful and relaxing Christmas, all the best until the new year 2022 and a lot of inspiration for radio hobbies.

Pavel Kraus

Guest Post: An Introduction to DXing the MF Marine Bands

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Many thanks to SWLing Post contributor, Don Moore–author of Following Ghosts in Northern Peru–for the following guest post:

Monitoring the MF Marine Bands

By Don Moore

For me, DXing has always been about the challenge of receiving difficult-to-hear radio stations, regardless of the type of station or frequency range. In my five decades in the radio hobby I’ve logged a lot of different kinds of stations – shortwave broadcast, medium wave, shortwave utility, longwave beacons, etc. But some of my favorite catches have been in the upper end of the medium frequency range.

Technically speaking, medium frequency (MF) is the range from 300 to 3000 kHz and includes the standard medium wave (AM) broadcast band. The upper end of the MF band, from 1600 to 3000 kHz (except for a small portion reserved for amateur radio), has always been assigned to various types of utility uses including broadcasts and other voice communications from regional maritime stations. And while digital modes and satellites have done a lot to change the nature of communication with ships at sea, there is still a lot of good human-voice DX to be heard.

Several dozen stations, mostly in Europe and North America, broadcast regularly scheduled marine information broadcasts in the MF range. These broadcasts are usually between five to ten minutes in length and include weather forecasts, navigational warnings, and other notices to keep ships at sea safe. On occasion it’s possible to hear two-way voice communication here between ships and shore stations, although that’s much less common today.

The Equipment

Nothing special is needed to DX the marine MF band other than a receiver that covers the frequency range and can receive USB mode (which all these broadcasts are in). However, for reasons explained below, I highly recommend using an SDR to make spectrum recordings of the entire band to go through later. Continue reading →

Airspy HF+ Discovery & Shortwave Portables: Having Fun with the Airspy YouLoop!

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Many thanks to SWLing Post contributor, Bill Hemphill, who shares the following guest post:

YouLoop Antenna Fun

by Billy Hemphill WD9EQD

Like many listeners, I live in an antenna restricted community. While I have strung up some hidden outdoor wire antennas, I have found that they didn’t really perform that much better than just using the telescoping antenna with maybe a length of wire attached. The biggest problem (whether indoor or outdoor antenna) has been the high noise floor.

A few months ago I bought an AirSpy HF+ Discovery SDR receiver. I had already owned a couple of SDRPlay SDR receivers, but the high noise floor limited their performance. I had read good reviews about the AirSpy, especially its performance on the AM Broadcast band and the lower shortwave bands.

I have about 80 feet of speaker wire strung from the second floor and across the high windows in the living room. This does perform fairly well, but the high noise floor still exists.

A couple of weeks ago, I bought the YouLoop Magnetic Loop antenna from AirSpy. I gave it a try and am amazed at the lower noise floor compared to the indoor wire antenna.

Wire Antenna vs. YouLoop–some examples:

AirSpy with Wire Antenna

AirSpy with YouLoop

AirSpy with Wire Antenna

AirSpy with YouLoop

AirSpy with Wire Antenna

AirSpy with YouLoop

Dramatic reduction in the noise floor. I’ve done a lot of playing around with it and find that the YouLoop picks up just about the same stations as the indoor wire antenna does. But with the lower noise level, the YouLoop makes it more enjoyable to listen. Overall, the YouLoop is now my main antenna.

YouLoop with a Portable Radio

It works so well with the AirSpy, I started wondering if I could use it with a portable radio, like the Tecsun PL-880. But the AirSpy website has the following note:

Note: It is very likely your third party radio will not be sensitive enough to operate with the YouLoop properly. We have even seen self-documented failed attempts to build pre-amplifiers to compensate for the lack of sensitivity and/or the required dynamic range in third party radios. Use your brain, and eventually an Airspy HF+ Discovery.

Doesn’t sound like it will work with portable radios. BUT, I’m always one to try anyway.

Tecsun PL-880

Since the YouLoop has a SMA connector, I bought a SMA to 1/8” phone jack cable. Plugged it into the PL-880 antenna jack and found I had almost a dead radio. Very few stations heard. But in playing around, I accidentally touched the phone plug to the telescoping antenna and instantly got strong signals.

I did some very unscientific tests. I attached the YouLoop through the side antenna jack, did an ATS scan, then did the same with the YouLoop clipped to the telescoping antenna. Also did a scan with just the telescoping antenna fully extended.. I got some very interesting results. These were done one after the other, so there can be differences in signal fading, etc.

I have repeated the above test several times at different hours. While the actual number of ATS stations varied, the ratio between them remained fairly consistent to the above numbers.

From the above, it appears that the telescoping antenna circuit is more sensitive than the 1/8” antenna jack circuit. Maybe some attenuation is being added to the 1/8” jack since it’s more likely a higher gain antenna would be used there. Can anyone confirm that the circuit indeed attenuates thru the antenna jack?

The YouLoop seems to be a decent performer when directly clipped to the telescoping antenna. While not as good as a high gain outdoor antenna would be, it definitely is usable for indoor uses.

I also tested it clipped to the antennas of some other portable receivers. Tecsun S-8800, PL-330, Panasonic RF-2200 and Philco T-9 Trans-World receivers. All showed an increase over just using the telescoping antenna.

Some interesting notes:

The Tecsun PL-330 saw the same reduction in signal when directly plugged into the antenna jack as opposed to clipping on the telescoping antenna.

The Tecsun S-8800 did not show that much of a drop. I basically got the same number of stations when clipped to antenna as when I connected to the BNC jack:

In conclusion, I find that I can use the YouLoop with my portable radios to increase the signals on strong stations when used indoors. And it is quite the performer when used with the AirSpy HF+ Discovery SDR receiver. It easily portable and I find that I move it around the house as I need to. I just hang it off a window curtain rod. I may just order a second one so that my family room radio has one permanently attached to it.

Click here to check out the Youloop at Airspy.com.

Guest Post: Don targets rare Norwegian stations during Newfoundland DXpedition

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Photo by the Bjørnøya Meteorologiske Stasjon

Many thanks to SWLing Post contributor, Don Moore–author of Following Ghosts in Northern Peru–for the following guest post:

The Rarest DX?

By Don Moore

In mid-October I received an invitation to attend the annual DXpedition in Cappahayden, Newfoundland with Jean Burnell, John Fisher, and Jim Renfrews. It didn’t take long for me to say yes. Newfoundland is one of the best places in the world to DX from and all kinds of amazing stuff has been heard there. I was excited at the prospect of great medium wave DX and being able to log low-powered European private and pirate shortwave broadcasters.

But something else was at the top of my try-for list. One of my many DX interests has always been logging coastal marine stations in the 1600 to 3000 kHz range. In preparation I started checking online sources to update my spreadsheet of schedules. In going through a recently added section on Marine Broadcasts in the DX Info Centre website I came across listings for twice-daily weather broadcasts from Hopen Island on 1750 kHz and Bjørnøya (Bear Island) on 1757 kHz.

I didn’t remember ever seeing anything about broadcasts from these remote islands in the Norwegian Arctic before. Were these stations actually on the air, I wondered. And if they were, could I hear them in Newfoundland? Continue reading →