Category Archives: Guest Posts

Tom’s Recommendations: Earbuds and EQ Settings for Shortwave Listening

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

Earbuds for Shortwave Listening

by TomL

A few years ago I had bought the discontinued Sennheiser MM 50 earbuds for a cheap price on Amazon to use in my various radios. The portable radios in particular can use more fidelity because of their small, raspy speakers. I also like to listen without bothering others around me who might not want to listen. And earbuds are a LOT more comfortable for my ear lobes than any over-the-ear headphones I have ever used. Furthermore, the old Apple iPhone 4 earbuds were very harsh to listen to. However, a trade-off is that, generally, earbuds are somewhat fragile; one of the two pairs of MM50’s died through mishandling.

I was generally happy with them while listening to Shortwave broadcasters with a mix of news/talk and music. I especially liked them on Mediumwave listening; stations can sound surprisingly good when playing music. Then I tried using these earbuds on my Amateur Radio transceiver, a Kenwood TS-590S. I was impressed how clear they sounded with a lack of distortion, although there was too much bass. Fortunately, Kenwood supplies USB connected software with an TX & RX 18 band EQ (300 Hz spacing, not octaves).

Here is a frequency response chart I found from Reviewed.com for this model:

One of the notable things about these earbuds is the total lack of distortion. Most likely one of the reasons they sound so clear on Shortwave, which has many LOUD audio spikes.

I had not wanted to get Bluetooth earbuds. However, I had recently upgraded my cell phone and NO headphone jacks anymore! So, while I do not use Bluetooth yet for radios, I can see a time in the future to get a Bluetooth transmitter to plug into a radio with a headphone jack. I am reluctant since I do not like having to recharge my earbuds and I put in a lot of radio listening time. Am I supposed to buy two Bluetooth earbuds and swap while charging? Maybe in the future. And also, am I supposed to buy a Bluetooth transmitter for every non-Bluetooth radio I own? Not likely gonna happen.

In the meantime, I ordered cheap wired earbuds from Amazon. I had a $5 credit for trying Prime, so when I saw these Panasonic ErgoFit wired earbuds (RP-HJE120-K) for slightly over $10, I said to myself, “why not?”. Supposedly wildly popular, they are one of the most rated products on all of Amazon with 133,821 ratings/opinions (perhaps Russian bots?!?!?).

Here is a frequency response chart from ThePhonograph.com for these Panasonic earbuds:

You can see comparatively that the bass response in the very good Sennheiser MM50’s is much stronger, being good music earbuds. But for voice articulation, not as much, even though they have no distortion. The Panasonic ErgoFit’s have more modest bass, less of a dip in the lower midrange audio frequencies, and more importantly, has a peak near 2500 Hz and its harmonic 5000 Hz. The highest highs are also modest compared to the Sennheiser model. This general frequency response to “recess” the bass and treble frequencies and peak the 2500 Hz is very useful for voice intelligibility.

As described by the famous speaker-microphone-sound-system maker, Bob Heil relates what he learned from the scientists at Bell Labs many years ago. Speech intelligibility is enhanced when audio is compensated for our natural human hearing. Equalizing below 160 Hz, reducing the 600-900 Hz region, and peaking the 2000-3000 region centered at 2500 Hz will increase intelligibility dramatically. The story goes that Bell Labs was tasked by parent AT&T with finding out why the earliest phones in the 1920’s sounded so muffled and hard to understand. After many experiments, the scientists found the most important frequencies for our ears + brain to comprehend speech. In other words, our ears are not “EQ-flat” like a scientific instrument is. Continue reading →

Spread the radio love

Don Moore’s Photo Album: Santa Bárbara, Honduras

6 Replies

Many thanks to SWLing Post contributor, Don Moore–noted author, traveler, and DXer–for the following Photo Album guest post series:

Don Moore’s Photo Album: Santa Bárbara, Honduras

by Don Moore

I first set foot in Latin America in January 1982 when I arrived in Tegucigalpa to begin three months of Peace Corps training. Three months later I moved to my Honduran home, the town of Santa Bárbara in the western mountains. For the next two years I worked as a teacher and resource person at the Escuela Normal Mixta de Santa Bárbara, a specialized high school that trained its students to teach primary school.

Santa Bárbara had a shortwave station, La Voz del Junco on 6075 kHz but it was rarely reported because it broadcast irregularly and was usually blocked by big international broadcasters when it was on the air. I had never heard it but I met Miguel Hasbun, the owner-manager, on my first visit to Santa Bárbara when he picked me up hitchhiking north of town. He told me that the shortwave transmitter had been broken down for a while but that he was going to fix it ‘soon’. Over the next year I kept inquiring about the shortwave and he finally did fix it. After that the station broadcast irregularly for the next year or so, mostly in the morning. I served as volunteer veri-signer and issued around fifteen QSLs. I even issued one to myself.

Santa Bárbara had one other radio station, Ondas del Ulúa on 1140 kHz medium wave (later 1150 kHz). They also announced 4770 kHz shortwave in their canned IDs and station staff assured me they would be adding shortwave “soon”. It never did happen but the WRTH did list the frequency as future plans for several years.

Audio:

Ondas del Ulúa 1982 sign-off announcement mentioning 4770 kHz.

The department of Santa Bárbara had one other radio station, Radio Luz y Vida on 1600 and 3250 kHz in the town of San Luis. The founder, manager, and veri-signer for Radio Luz y Vida was a missionary from Oklahoma named Don Moore. Needless to say, this caused a lot of confusion in the DX world as some people assumed he and I were the same person. On the map, San Luis is only about thirty kilometers from Santa Bárbara but getting there involved a five-hour journey on two buses. I only went once and the other Don Moore was out of town, so I never met him. I did meet two nurses who were working at the mission’s health clinic.

Photos

These pictures were all taken in 1982 to 1984 while I lived in Santa Bárbara [click on photos to enlarge].

La Voz del Junco’s yellow sign on main street in downtown Santa Bárbara. The small tower on the left was the corner of what had been an army post but was being used as a regional prison in the early 1980s. I once went there every day for a week to supervise student-teachers doing adult literacy classes for the inmates. It was not a pleasant place to be.

Entrance to La Voz del Junco. The girl is examining a poster for the night’s showing at the makeshift movie theater that Don Miguel operated nearby. Continue reading →

Spread the radio love

From SolderSmoke: Watching Shortwave Broadcast Stations on the TinySA Spectrum Analyser

3 Replies

Curtain Antennas at VOA Site B: Greenville, North Carolina.

Many thanks to SWLing Post contributor and friend, Bill Meara, from the amazing SolderSmoke podcast who shares the following post that originally appeared on the SolderSmoke Daily News:

Watching Shortwave Broadcast Stations on the TinySA Spectrum Analyser

by Bill Meara

November 18, 2022 1244 UTC. I was using a TinySA spectrum analyzer to look at noise levels on the 40 meter ham radio band. I also wanted to take a look slightly above the band (in frequency) to see Radio Marti at 7355 kHz. As I was doing this I remembered that Vatican Radio was on the air at 7305 kHz from 1230 UTC to 1245 UTC. So was just going to catch the last moments of that day’s transmissions. Sure enough, I caught it, and watched it disappear from the TinySA screen. See the video below:

Click her to view on YouTube.

Radio Marti continued on. In the morning we can hear the rooster recordings from that station. We are using it to test how well our homebrew Direct Conversion receivers avoid AM detection. In the video I mistakenly said these two transmitters were on the air with 250 megawatts. The correct power is 250 kilowatts. Both transmit from Greenville NC. I think the signal from Vatican Radio is stronger here because they are using a different antenna pattern — Radio Marti is aimed at Cuba.

This reminds me of a cool project I have not yet done: modifying the TinySA to allow the user to listen to the station: https://soldersmoke.blogspot.com/2021/10/how-to-listen-with-your-tinysa.html I notice that Dean KK4DAS (my colleague in DC receiver design) was the only commenter on the blog post describing the TinySA mod. TRGHS. We need to to do this.

Here are the reports showing when Vatican Radio and Radio Marti were on the air on November 18, 2022:

Thank you for sharing this, Bill. I love it! The TinySA is such an affordable and useful workbench tool.

Post readers: If you love building things and exploring a wide range of radio projects, I highly recommend bookmarking the SolderSmoke Podcast and website.

Spread the radio love

Frank reports on the Deshibo RD1860BT portable shortwave receiver

10 Replies

Many thanks to SWLing Post contributor, Frank, in Germany, who shares the following guest post and review of the Deshibo RD1860BT:

Deshibo RD1860BT report

Hello Thomas,

Today I would like to report on a new portable world receiver. Unfortunately, new devices have not been found on the shelves of electronics retailers for a long time, but now in the depths of the world wide web. And that’s how I came across the Deshibo RD1860BT.

Deshibo is certainly known to many from their GA450 loop antenna. But Deshibo has also produced several radios, including the RD1780L, which is probably a little better known. New to the segment is the RD1860BT, which initially seemed like an old friend to me. An Eton Elite Executive? Yes, there are external similarities, but also differences.

Many months ago I had an Eton Elite Executive for a short time. I had heard of its excellent reception properties, which I can confirm, but the design is reminiscent of older receivers from the 80s, is relatively heavy, operation is sometimes a bit cumbersome, the protective cover does not protect properly. I find the device to be portable overall difficult. We didn’t become friends, so I sold it on to a Swede, who in turn became a friend.

I still missed the Eton. RDS on VHF is not found in any Tecsun , nor are there memory banks that can be written on.

Then I discovered the RD1860BT and couldn’t resist. First of all: the Deshibo is only labeled in Chinese for important function keys. But the friendly dealer on eBay provided me with an English manual before I bought it. That was the deciding factor, because I was sure that after a little use , the Deshibo could be operated blindly.

However, some questions have arisen in the user manual. Some things didn’t seem quite right, others were completely missing from the description. That’s why I decided to write my own manual on a journey of discovery of the new Deshibo. And so that it might also help others who might be interested in radio, I wrote it in English and attach it here.

Click here to download Frank’s version of the RD1860BT manual (PDF).

The Eton’s somewhat unsorted manual was very helpful, but I also added my own drawings. For example, I added an English-labeled keyboard as a back cover, so that the keys can be assigned without a long search.

Here you can already find the first differences to the Eton: the keyboard layout is a bit more orderly. Also, the Deshibo doesn’t have a metallic speaker grille (which frankly I don’t like about the Eton). The display, not the writing, is backlit in orange on the Deshibo . Most importantly, the Deshibo is a lot lighter than the Eton ( around 500g if I researched correctly). And that means: the structure of the Deshibo must be different. Continue reading →

Spread the radio love

Guest Post: Monitoring Digital Selective Calling (DCS) with YADD

7 Replies

Many thanks to SWLing Post contributor, Don Moore–noted author, traveler, and DXer–for the following guest post:

Monitoring DSC with YADD

By Don Moore

(The following article was originally published in the April/May 2022 edition of the Great Lakes Monitor, bulletin of the Michigan Association of Radio Enthusiasts. An all-band listening club, MARE publishes a bi-monthly print bulletin and a weekly e-mail loggings tip-sheet. The club also holds regular get-togethers, picnics, and DXpeditions, generally in southeastern Michigan.)

There are dozens if not hundreds of different digital modes used for communication on the MF and HF bands. These aren’t broadcasts you want to listen to unless you like to hear weird tones, beeps, warbles, and grinding noises interspersed with static. Digital modes are for monitoring, not listening. And monitoring them requires having software that does the listening for you and converts the noises into something meaningful – like the ID of the station you’re tuned to. The learning curve to DXing digital utilities can be steep. There are lots of modes to identify and the software can be complicated to learn. Some broadcasts are encrypted so you can’t decode them no matter how hard you try. But the reward is lots of new stations and even new countries that you wouldn’t be able to add to your logbook otherwise.

One of the easiest digital modes to DX is DSC, or Digital Selective Calling. DSC is a defined as “a standard for transmitting pre-defined digital messages.” Look online if you want to understand the technical specifications that specify the values, placement, and spacing of the tones. The result of those specifications is a string of three-digit numbers like this:

125 107 125 106 120 105 120 104 000 120 022 120 041 000 002 022 020 041 108 002 053 020 080 108 006 053 021 080 070 006 118 021 126 070 126 118 126 126 126 126 126 126 126 126 126 126 117 126 112 126 117 117 117 112 109 125 108 125

Each three-digit value represents either a digit or a key word and the positions of the values map to the various fields contained in the message. This message, which was received on 8414.5 kHz, is a test call from the tanker Brook Trout to the coastal station Coruña Radio in Spain. The sender and destination are not identified by name but rather by their nine-digit MMSI (Maritime Mobile Service Identity) numbers – 538006217 for the vessel and 002241022 for the coastal station.

GETTING STARTED WITH DSC

Logging DSC stations requires three pieces of software. First you need a decoder program that turns the noises into numbers and the numbers into meaning. There are several free and commercial options but the most popular one for beginners is YADD – Yet Another DSC Decoder. YADD is free and easy to set up and while YADD can be used by feeding the audio from a traditional radio into your computer, the most common use is with an SDR. That’s what I use and what I will describe here.

Second you need an SDR application and an SDR. I prefer HDSDR for most of my SDR use but I like SDR-Console for digital work. But any SDR program will work if you can feed the audio to a virtual audio cable. And that’s the final thing you need – a virtual audio cable to create a direct audio connection between your SDR application and YADD. There are several different ones available but I recommend VB-Cable. Your first VB-Cable is free and that is all you need to run a single instance of YADD. If you want to expand you can buy up to four more cables from them later. Continue reading →

Spread the radio love

Don Moore’s Photo Album: Ecos del Torbes

10 Replies

Many thanks to SWLing Post contributor, Don Moore–noted author, traveler, and DXer–for the following guest post series:

Don Moore’s Photo Album

by Don Moore

Introduction

When I discovered DXing over fifty years ago I also discovered the world. Through my ears I traveled to other countries and explored other cultures. But DXing has also literally taken me places. My early interest in Latin American DXing developed into a broader interest in Latin America. That led to me joining the Peace Corps after college and working three years in Honduras. That experience furthered my interest in Latin America and I have continued to travel in the region whenever possible. For me DXing and travel were always intertwined. I’m one of a handful of hobbyists who took DXing beyond just listening and went knocking on broadcasters’ doors to visit the distant stations I heard. My ex-wife dubbed this ‘door-to-door DXing.’

To date I’ve visited over 150 radio stations in thirteen countries. A few were medium-wave or FM only, but I was always most interested in visiting broadcasters that used shortwave, either at the time of my visit or a few years before. As my station visits were primarily made in the 1980s and 1990s, almost all of the stations are long-gone from the shortwave bands. However, many are still around on medium wave and FM and often also via streaming on the Internet. As much as I miss the magic of shortwave I know that these stations reach more listeners today via streaming than they ever did with their low-powered shortwave transmitters. Honestly, I sometimes enjoy tuning them in without the fading and static of shortwave. But the memories of what shortwave once was are still there.

Photos also bring back memories. I took dozens of pictures on my station visits and enjoy scrolling through them now and then. You may have seen some of them. Many of my photos were printed with articles I wrote for various DX publications and I’ve done a few slide-shows at DX get-togethers over the years.

In this series of columns I want to share my old photos once again. If you’ve been DXing as long as I have maybe they’ll bring back memories of what you once heard. And if you haven’t been around that long you will have a better understanding of the good old days we oldtimers talk about.

Ecos Del Torbes

There is no better place to start this journey than with Ecos del Torbes. Using ten kilowatts on 4980 kHz, this Venezuelan broadcaster was possibly the most consistent station in the sixty-meter band throughout the 1970s, 80s, and 90s. If you were DXing the tropical bands during those years you surely logged them a few times. If you were lucky you may even have heard their one kilowatt signal on 9640 kHz. They were a very good verifier and for many DXers Ecos del Torbes was among the first Latin American stations QSLed.

Just after Christmas in 1994, my then-wife, four-year-old daughter, and I flew to Mérida in western Venezuela for a family vacation. For ten days we had a great time in this Andean city and then Theresa and Rebecca returned to Iowa while I stayed another week to visit radio stations. I was also getting paid by the Voice of America to research and write a study on the media scene in Andean Venezuela. The now very-out-of-date report can be read at my Patepluma Radio website (which hasn’t been changed in over twenty years and is in need of a facelift).

In that week I visited fifteen radio stations in six towns and cities and Ecos del Torbes was the highlight. I arrived at their doorstep unannounced but was immediately treated as an important guest. I was given a great tour and even got to sit in on a live newscast to see the famous Venezuelan doorbell being used live. I was there about ninety minutes and then walked a block up the street to sister station Radio Táchira. Their facilities were smaller but that’s where the technical offices were and Chief Engineer Ivan Escobar had been told to expect me. Ivan gave me a tour and invited me to visit the Ecos del Torbes transmitter site with him in the afternoon. On the way we stopped by his house where his wife had lunch waiting for us. Visiting Ecos del Torbes was not just the highlight of this trip but ranks as one of my all-time favorite station visits. These pictures bring back many good memories.

Photos

Ecos del Torbes was located in the second floor of this building in downtown San Cristóbal. The entrance was the door on the side.

The small plaque next to the door was easy to miss. I walked right by the first time.

Edgar Fabala of the news department showed me around. Here he demonstrates the mini-xylophones that Venezuelan stations used to make the distinctive ‘doorbell’ sound that separated items in the news reports.

Announcer in the studio preparing to read the news.

The adjoining control room.

Ecos del Torbes had one of the largest record libraries in Venezuela. The LPs were color-coded by type.

Julio Achila was a control room operator who had worked at the station since it opened in 1947.

This pennant was considerably larger than the ones sent to DXers.

Sister station Radio Táchira was located a block up the street on the fourth floor of this building.

The Ecos del Torbes transmitter building.

The 50 kilowatt medium wave transmitter on 780 kHz.

Chief Engineer Ivan Escobar and Don Moore next to the 31 meter transmitter. The larger transmitter was for the well-heard 4980 kHz frequency.

The antenna array used for 4980 kHz. The medium wave tower is in the background.

Dipole antenna used for 9640 kHz.

San Cristóbal once had a third broadcaster on shortwave. Radio San Sebastian used 6070 kHz in the early 1970s. (They were not affiliated with Ecos del Torbes).

That was nearly three decades ago and a lot has changed. Ecos del Torbes and Radio Táchira have been gone from shortwave for over twenty years.

In 1995 Ecos del Torbes was at the corner of Calle 9 and Carrera 8, the same address as when I first QSLed them in 1972. Sometime since my visit they moved an outer neighborhood about two kilometers to the east. To find the new offices locate San Cristóbal on Google maps and then search for “Grupo Radial Gonzalez Lovera”. The transmitter site is still where I visited it and can be seen by plugging the coordinates “7.7885, -72.2725” into Google maps and switching to satellite view. (Ignore the picture that pops up to the side. That’s not it.) Zooming in, the medium wave tower is clearly visible but there are no signs of the old shortwave antennas. I suspect they were sold for scrap years ago. I never have found out where the Radio Táchira transmitter site was.

I’d love to go back to Venezuela someday and see some of the other cities that I used to listen to, such as Barquisimeto, Valencia, El Tigre, and Sucre. Unfortunately the political and economic situation there doesn’t look good and it doesn’t look as if it will improve any time soon. But when it does, I’ll be back.

Click here to check out all of Don Moore’s Photo Album columns. Each new article will appear on the SWLing Post home page/feed and in this link.

Spread the radio love

Julian reviews the Panasonic RF-B45 and shares comments regarding shortwave broadcasting and portable radios

23 Replies

Many thanks to SWLing Post contributor, Julian S, who shares the following guest post and review:

Panasonic RF-B45 – A Comparative Review

by Julian S

18 and 19 October, 2022

I was raised on valve / tube radios. From my pre-teens in the 1960s, I enjoyed tuning through the frequencies as a form of exploration. In the 1970s I experimented with antennae to improve reception. And later, starting in the 1980s, I began to use travel radios, always looking for that perfect radio.

Today the perfect radio for us SWL’ers might need to include a time machine to take us back to the halcyon days of SW, say in the 1980s or 1990s, before so many Western broadcasters axed their Short Wave services.

Looking at the BBC World Service’s latest round of cuts, I am filled with horror. Is whoever decided those cuts deeply cynical or deeply ignorant?

Switching BBC World Service content from radio to the internet for countries that block or restrict internet access is not the way to reach people living there. In places where every person’s internet access is monitored, where access to websites and web-content is censored or blocked, BBC news internet content will not be widely available. Today and for the foreseeable future the way to reach perhaps half or more of the world’s population is radio, especially Short Wave radio broadcasts.

The People’s Republic of China (PRC) and other like-minded countries, eg the DPRK (North Korea) fully understand the importance of radio, especially Short Wave and they vigorously maintain multiple Short Wave broadcast programmes as a way to project soft power and influence people.

In this context, it’s no surprise that when the Australian Broadcasting Corporation in 2017 suddenly, unexpectedly and against a back-drop of protests from Pacific Island Nations and rural Australians ditched its Short Wave broadcasts, the PRC’s China Radio International grabbed Australia’s SW frequencies.

I heard that in an earlier round of cuts China acquired frequencies dropped by the BBC World Service.

By the time the West wakes up again to the importance of Short Wave radio broadcasting as a means to communicate to the world, they will find the SW airwaves are full of PRC, North Korean, Vietnamese, Cuban and other broadcasters who never forgot how important SW broadcasts to the world are. I’m reminded of a line from the Sean Connery film, Rising Sun, “If you don’t want us to buy it, don’t sell it.”

Aside from the broadcasters mentioned above, there are still many others broadcasting on SW and there are plenty of Hams too. Short Wave radio listening and Ham radio are widespread and popular in Asia and Africa and are a major source of news. In some countries SW is also used as a means of business and social communication. So much so that there are home-grown radio and transceiver manufacturers in a number of African and Asian nations.

SW listening is big in China. So it’s no surprise that probably the best manufacturer of consumer grade short wave radio receivers is a China based company, Tecsun, who need no introduction. Tecsun seems to have taken over the role that was once held by Grundig, Sony, Panasonic and others. Indeed many of the later Grundig models are made by Tecsun.

If you’ve guessed that I like short wave radio, you’ve guessed right. And I suppose like many other fans, I usually have my eye open for something special.

Since hearing of the Panasonic RF B65 some years ago, I’ve been on the look-out for one at a reasonable price… this search led me to the RF B45…. But I’m a man of modest means so I need them to be priced accordingly.

Usually these two 30+ year old radios are priced on North American eBay like holy grail radios. More expensive than a 2nd hand Sony ICF 2010 / 2001D. Go figure. But the other day I found a Panasonic RF B45 for what I considered a reasonable price. It arrived yesterday, well packed, clean and in good condition. After dinner and this morning before breakfast I put it through some of its paces

What follows are some initial impressions of the Panasonic RF B45:

I’ve read a few reviews of it on eham, shortwave.ch etc. The controls are pretty easy to figure out. It has a similar form factor to the Sony ICF7600 series and is probably comparable in performance to the digital iterations of the Sony 7600 series… though the only 7600 series radio I have at present is the analogue 7601 which is comparable to the Tecsun R9700DX, except in price. New the Tecsun R9700DX is likely to be cheaper than a used Sony 7601 on eBay, and the Tecsun has a wider range of features, eg external antenna socket, comes with a long wire antenna, has better audio… but I digress…

…back to the Panasonic RF B45. This is a fine compact travel radio about the size of a paperback book or two DVD stacked boxes. Continue reading →

Spread the radio love