Category Archives: Mediumwave

WRTH 2021: A look inside the 75th Anniversary Edition!

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Last week, I received a long-awaited Christmas gift: the 2021 World Radio TV Handbook. Normally, I’d receive this annual guide in the December time frame, but because of delays in international postal services due to the Covid-19 pandemic, I took delivery a few weeks late.  

I always look forward to receiving this excellent staple radio reference guide–and this is their 75th edition! As I say each year, the WRTH has never disappointed, so my expectations are always quite high.

Once again, the WRTH lived up to my expectations.

WRTH’s team of noted DXers from around the world curate frequencies and broadcaster information by region; while I’m not sure how they orchestrate all of this, the end result is truly a symphony of radio information. In addition to broadcaster listings, WRTH’s radio reviews, feature articles, and annual HF report make for excellent reading.

But the WRTH isn’t just a frequency guide: the publication always devotes the first sixty or so pages to articles relating to various aspects of the radio hobby. Following, I offer a quick overview of these.

The first article always features a WRTH contributor:  this year, they feature Stig Hartvig Nielson. His path to becoming a WRTH contributor began in his childhood when he said he was “tall enough to reach the radio tuning knob and tune away from dull Radio Denmark.”  His love of radio lead him down the path of becoming a broadcaster. Many of us know him via his station, Radio208.

WRTH Reviews

The second set of articles is always my favorite: WRTH receiver reviews.

This year, WRTH begins with an in-depth review of the AOR AR5700D wideband communications receiver–a radio I’d likely never touch in real-life, so it’s wonderful to take such a deep dive.  Next up is a review of the Bonito NTi MegaDipol MD300DX antenna which gets high marks for high gain, low noise, and good dynamic range. The following in-depth review is of the benchmark Icom IC-7610 general coverage transceiver. This was the first time I’ve read a review of this SDR transceiver with radio listeners in mind. WRTH then review the Bonito NTi CCMC30 common mode noise filter–a tool that can help radio enthusiasts mitigate RFI.

A review of the SDRplay RSPdx follows and the review speaks to the performance improvements included with the new HDR mode. The next review is actually one I authored of the Tecsun PL-990 portable radio–it’s always an honor to be in the pages of the WRTH!

The final review is of the Valent F(x) KiwiSDR; a little web-connected SDR receiver that has certainly transformed the nature and accessibility of remote listening.

WRTH Features

The first feature article, written by none other than Dave Porter, focuses on the development of HF broadcast transmitters. This article adds to the one he authored last year which focused on broadcast antennas. Dave is amazing because he has such an extensive history in the world of HF broadcasting and his experience and expertise are obvious in all of his writing. This is a must-read for those who want to know more about the “business side” of an international broadcast signal!

Manfred Rippich’s feature, Radio in Bhutan, explores the story of broadcasting in one of the most mountainous countries in the world where communities–including the capitol–are not easily accessible. Radio broadcasting plays an important role in this amazing country.

The following feature, Coastwatchers & the AWA Teleradio 3BZ written by Dr Martin Hadlow, takes a look at the importance of portable radios in the Pacific War. An absolutely fascinating piece for those of us who love radio history.

The final feature was written by Alan Pennington and explores the dynamic Scandinavian Weekend Radio.  It’s hard to believe SWR has celebrated 20 years on the air as of 2020. Pennington’s article explores the grassroots energy of this unique broadcaster!

The final article–a tradition–is the WRTH  HF propagation report/forecast by Ulf-Peter Hoppe. Always an informative read especially as we continue to work our way out of a long-term solar slump.

The 75th is another fantastic edition of the World Radio TV Handbook. As I say every year, I’ve never been disappointed with WRTH. Their publishing standards are such that the quality of their reviews, their writing, and (most importantly) their broadcast listings are simply unparalleled.

For DXers who collect QSL cards, you’ll find that broadcaster contact information in WRTH is often more up-to-date than a broadcaster’s own website. When readers contact me asking for QSL information from an obscure broadcaster, the first place I search is the current WRTH. Remember: their information is based on volunteer contributors who specialize in specific regions of the world–the most knowledgeable regional DXers keep this publication accurate.

Purchase your copy of WRTH 2020 directly from WRTH’s publishers, or from a distributor like Universal Radio (US) , Amazon.com (US),  or the Book Depository (international).

National Public Broadcasting Company of Ukraine resumes mediumwave broadcasting

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Many thanks to SWLing Post contributor,  Vlad (US7IGN), who writes:

Hello!

I hasten to inform you the good news that Ukrainian radio resumes broadcasting on medium waves.

At a time when the whole world is curtailing broadcasting, a new station has appeared on the air!

From February 1, the National Public Television and Radio Company of Ukraine will resume broadcasting UA: Ukrainian radio in the medium-wave band on the frequency 549 KHz.

The medium-wave transmitter of UA: Ukrainian radio in the village of Luch, Mykolaiv region, with a capacity of 500 kW, covers most of the territory of Ukraine (during the day – 60% of the territory including the occupied territories, from evening to morning – the whole territory of Ukraine).

http://uarl.info/news/ukrainskoe_radio_vosstanavlivaet_veschanie_na_srednih_volnah

Brilliant news–many thanks for the tip, Vlad!

Loop-On-Ground Antenna Part 2: Tom upgrades his low profile, low noise, portable DXing antenna

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

Loop on Ground Part 2

by TomL

My previous Loop on Ground (LoG) experiment was useful which entailed connecting my Wellbrook loop amplifier to a 100 foot loop of speaker wire in the field at my favorite local Forest Preserve. It really brought in stations I had never heard before or strong stations in a more powerful way that made the audio really pleasant to listen to.  This report will describe more experiments with smaller wire loops to see what the limitations are.  100 feet of wire is quite a lot of wire to mess around with especially in the cold weather or public places that do not have as much private space.

I don’t understand all the electrical interrelationships but a long posting at RadioReference.com had  a great discussion about creating a 160-20 meters LoG receive-only antenna. It is 11 pages long but is worth reading how “nanZor” experimented with various parameters for general use. Kudos to him for documenting the findings as the design changed over time. You can find it here:

https://forums.radioreference.com/threads/160-20m-log-loop-on-ground.370110/

nanZor basically boils it down to a few guidelines.

  1. Keep it on the ground. Lifting the wire more than an inch or two decreased the lower angle signal reception greatly.
  2. Calculate the optimal length for one full wavelength of wire at the highest target frequency, say for example, the top of the 20 meter band (14350 kHz). 936/14.350 MHz * 0.9 velocity factor of simple insulated wire = 58.7 feet.  You can round up to 60 feet, no big deal since this is broadband.  The antenna should have a predictable reception pattern from 1/10th wavelength up to 1 full wavelength. Outside that range, the pattern gets “squirrely”.
  3. Using a 9:1 balun seemed to be a little better than a 4:1 balun at the antenna feedpoint. This gets into things I cannot measure and has to do with rising impedance as a loop gets closer to ground level. I am not sure but I think my Wellbrook amp has a built in 4:1 balun and it seems to work just fine.
  4. Make sure to use an RF Choke at BOTH sides of the feedline coax cable. He was adamant that the loop can get easily unbalanced and allow noise into the antenna and/or feedline and so it must be isolated and the ground allowed to “float” in his words.

Personally, I also wanted to use less wire and happened to have a length of 42 feet of landscape wire which should work well below 5 MHz with the Wellbrook amp engaged.  Results were not bad even though on hard frozen ground. Signal levels were down a little compared to the 100 foot of wire.  Here are a couple of examples, first one in a fast food parking lot with a grass field next to it and second at the usual Forest Preserve parking lot on a grass field.  I made sure that my car blocked the view of the wire so people would not get nervous!

La Voz Missionaria, Brazil:

Voice of Welt from Issoudun France in Kurdish:

These are not necessarily “DX” but definitely good for SWLing. I like the signal strength with the amplifier inline at the antenna feedpoint and I did not have to use an RF Choke at the receiver side as was suggested.

I had a 75 foot long insulated wire and used that at the Forest Preserve parking lot on a couple of different days.  Lower frequency signal strength and signal/noise ratio improved a little bit to be noticeable.

US Air Force HFGCS “numbers” station. Remote controlled from Andrews or Grand Forks bases (https://en.wikipedia.org/wiki/High_Frequency_Global_Communications_System), there was no way for me to know which of the 6 transmitters it was coming from:

BBC from Tinang Philippines in Korean:

Then, as nanZor suggested in his postings, I purchased a 9:1 balun/RF choke (it has both a balun and an RF choke built-in) from Ham Radio Outlet and put that in place of the Wellbrook amplifier.

I have not worked with it, but it is reported that the Nooelec.com v2 model is cheaper and works just as well – https://swling.com/blog/2019/10/the-nooelec-balun-19-v2/

Examples below with the 42 foot loop and 9:1 balun/choke, no amplifier:

KSDA, Agat Guam in English

WB8U doing a POTA activation of Leavenworth State Fishing Lake

VOLMET weather, Shannon Ireland

HCJB Quito Ecuador, probably in Quechua

As a side note, there is a posting that mentions low-angle DX is better with regions that have better “ground conductivity”, salt water being the best. I have no way of verifying this.  See post# 126 by KK5JY Matt.

So, bottom line is that a Loop on Ground can be useful for pleasant SWLing and portable.  Best to use it on grass, not asphalt.  The loop amplifier is useful to get signal levels up if you have to use a smaller loop size but the signal/noise ratio will suffer due to its smaller aperture.  And, warning, the public will find a way to trip over the wire no matter where you set it up (I may try putting the wire around my car if I can park on a grass surface and/or use the gaudiest, brightest neon green or orange wire I can find – they can’t trip over THAT, can they?).

TomL

Thanks, Tom, for sharing your update. Obviously, the LoG is working brilliantly. It’s amazing that you got such clear reception from the parking lot of a fast food restaurant.  If you were using a vertical instead, I bet signals would have been buried in the noise. 

I can also relate to people tripping over antenna wires. I remember one POTA activation recently (the first activation in this three park run) where I intentionally laid my counterpoise on the ground, off a foot path, in the brush and where I couldn’t imagine anyone ever stepping. Ten minutes into the activation and for no reason, someone walked off the path, into the brush, and it snagged them. Maybe I’m just a Ninja level trapper and never realized it!?

Thanks again for sharing the results of your LoG, Tom. Inspiring! 

Is AM synchronous detection a crucial portable radio feature?

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Many thanks to SWLing Post contributor, Mike, who writes with the following question:

How important is AM Sync for a portable radio? Is it essential or a deal breaker?

That’s a great question, Mike, and one I don’t think I’ve directly addressed it here on the SWLing Post oddly enough.

Synchronous detection is actually a fairly deep topic to explore–and everyone has their own opinion–but I get the impression that you’d like a simple answer, so I’ll try to keep this as brief as possible. You might follow the comments section of this post as I’m sure some SWLing Post readers will share their thoughts on synchronous detection and how important it is for them.

So what is Synchronous Detection?

I like this concise Wikipedia answer:

In electronics, a synchronous detector is a device that recovers information from a modulated signal by mixing the signal with a replica of the un-modulated carrier. This can be locally generated at the receiver using a phase-locked loop or other techniques. Synchronous detection preserves any phase information originally present in the modulating signal. Synchronous detection is a necessary component of any analog color television receiver, where it allows recovery of the phase information that conveys hue. Synchronous detectors are also found in some shortwave radio receivers used for audio signals, where they provide better performance on signals that may be affected by fading. To recover baseband signal the synchronous detection technique is used.

How does synchronous detection help shortwave, mediumwave, and longwave listeners?

As the Wikipedia article notes above, sync detection can help “provide better performance on signals that may be affected by fading.”

In short: a solid synchronous detector can help stabilize an AM signal which then can help with overall signal intelligibility.

In some modern portable radios, at least, this could come at the expense of audio fidelity (see caveat below).

I use sync detection when the bands are rough, noisy, and QSB (fading) is affecting signals.

A good sync detector will help clean-up and stabilize the signal so that you can hear voice information with less listener fatigue. Sync detectors are also great tools for grabbing station IDs when propagation is less stable. If you have a receiver with selectable sideband synchronous detection, it can also be used as a tool for eliminating adjacent signal interference.

Caveat? Sync detectors vary in terms of quality.

The PL-880 has a synchronous detection “hidden” function. I’m sure it’s hidden because it’s so ineffective. The PL-880 is a fantastic portable, but don’t bother using the sync detector.

Many modern DSP portables sport synchronous detection, but they’re not terribly stable and the audio fidelity can take a big hit as well. Poor sync detectors can make audio sound “tinny” and narrow.

If a sync detector isn’t effective a providing a stable lock on a signal, then it’s pretty much useless. Why? If it can’t maintain a stable lock, it’ll produce very unstable shifting audio, often with the occasional heterodyne sound popping in as well. In those cases, it’s better to turn off synchronous detection.

Benchmark legacy tabletop receivers and modern Software Defined Radios (SDRs) typically have solid, effective sync detectors. Indeed, I rarely have the AM synchronous detector disengaged on my WinRadio Excalibur–that particular SDR and application enhance audio fidelity through sync detection.

I find that I use sync detection less with my Airspy HF+ Discovery and SDRplay RSPdx, for example, because the OEM applications natively does a brilliant job managing unstable signals.

In terms of portables, I’ve always considered the sync detector of the Sony ICF-2010, Sony ICF-SW7600GR, and PL-660/PL-680 to be pretty solid. I’m sure readers can suggest even more models.

Is sync detection an essential feature on a portable radio?

Not for me. But I do admit that I value the radios I own that sport a good sync detector.

For some SWLs and DXers, however? It might very well be a deal-breaker if a radio doesn’t have a sync detector, or if its sync detector doesn’t function well.

What do you think?

Is the lack of sync detection a deal-breaker for you? When do you employ sync? Please comment!

Giuseppe’s homebrew rotating ferrite antenna

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Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who writes:

Dear Thomas,

I’m Giuseppe Morlè (IZ0GZW) from Formia, on the Tyrrhenian Sea, in Italy .

I built this simple rotating directive ferrite antenna for medium waves and the 160 meters ham band.

Inside the tube there are 2 ferrites with 43 cable windings and 3 for the coupling link that goes to the receiver.

In this video the test as soon as I assembled everything …

In broad daylight, it was 12.00 local time, you could hear well over 2000 km.

The antenna is very directive and perfectly manages to separate several stations on a single frequency.

The pipes are in plastic for plumbing use (PVC), I bought only that one, 5 Euros, the rest is all recycled.

I wanted to share this simple and very functional project of mine with the SWLing Post community.

Thanks and I wish everyone a better year.

Greetings from Italy.
Giuseppe iz0gzw.

Thank you, Giuseppe! What a simple, effective antenna project. I like how you’ve invested so little and recycled parts from other projects. I also love your view there looking south over the Tyrrhenian Sea! What a great place for radio.

CBC Yukon features Finnish DXer who logged their station from 7,000 km away

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Image Source: CBC/Google Earth

(Source: CBC Yukon)

From Yukon to Finland: CBC’s radio signal heard from afar

Host Elyn Jones heard saying ‘this is Yukon Morning,’ about 7,000 kilometres away

A keen listener has managed to hear CBC Yukon’s radio broadcast from about 7,000 kilometres away.

Jorma Mäntylä lives in Kangasala, Finland.

On Oct.15 he was scanning the airwaves and came across the signal from Dawson City, Yukon, broadcasting CBC’s Yukon Morning show.

The signal lasted about an hour.

“It was clear to hear your Yukon Morning program led by a female journalist and the morning news,” he said.

The host that day was Elyn Jones in Whitehorse.

Upon hearing the signal Mäntylä sent an email with an attached audio clip asking for confirmation.

CBC Yukon wrote him back to confirm what he’d heard. We also scheduled an interview by videoconference to speak about his hobby.

No ordinary radio

Mäntylä doesn’t have an ordinary radio. He’s part of the Suomen Radioamatööriliitto, the Finnish Amateur Radio League.

He started listening to signals in 1967.

He uses custom-built equipment to scan for shortwave and AM radio signals.

Sometimes it takes a while, through the crackle, to determine the language being spoken and from where the signal is broadcasting.

The game is to discover new stations, identify them, and then send an email to confirm the reception.

“I very often listen to foreign radio stations. That has been my hobby for 50 years,” he said. ‘It’s given me interesting moments learning about other cultures and nations,”

Hearing a signal from Yukon is rare. Mäntylä says on Oct. 15 he also heard broadcasts from radio stations in Anchorage and Fairbanks, Alaska.

Click here to continue reading the full article.

Looking back at 2020: What radios were in heavy rotation at your home and in the field–?

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This morning, I’m looking at the calendar and I see and end in sight for 2020. I think most of us can agree that 2020 will be one for the history books, in large part due to the Covid-19 global pandemic which has had a pretty dramatic affect on many of our lives. It certainly brough my planned travels to a halt. I think many of us are quite happy to show 2020 the door!

As each year comes to a conclusion, I often look back at my radio activities during that year and see how it played out. I especially note the radios I used most heavily throughout the year.

Since I evaluate and test radios, models that are new to the market obviously get a lot of air time. Still, I’m also known to pull radios from the closet and give them some serous air time.

I’m very curious what radios you gave the most air time in 2020?

Here’s my list based on type/application:

Portable shortwave receivers

Since they’re new to the market, both the Tecsun PL-990 (above) and Belka DX (below) got a lot of air time.

I do like both radios and even took the pair on vacation recently even though packing space was very limited. I see the Belka DX getting much more air time in the future because 1.) it’s a performer (golly–just check out 13dka’s review of the Belka DSP) and 2.) it’s incredibly compact. The Belka now lives in my EDC bag, so is with me for impromptu listening and DXing sessions.

A classic solid-state portable that also got a lot of air time this year was the Panasonic RF-B65. Not only is it a performer, but it has a “cool” factor that’s hard to describe. I love it.

Tabletop portables

In a sense, the C.Crane CCradio3 got more play time than any of my radios.  It sits in a corner of our living area where we tune to FM, AM and weather radio–90% of the time, though, it’s either in AUX mode playing audio piped from my SiriusXM receiver, or in Bluetooth mode playing from one of our phones, tables, or computers. In October, the prototype CCRadio Solar took over SiriusXM duty brilliantly. I’m guessing the CCRadio3 has easily logged 1,600 hours of play time this year.

Of course, the Panasonic RF-2200 is one of my all-time favorite vintage solid-state portables, so it got a significant amount of field time.

Software Defined Radios

While at home the WinRadio Excalibur still gets a large portion of my SDR time, both the AirSpy HF+ Discovery and SDRplay RSP DX dominated this space in 2020.

The HF+ Discovery was my choice receiver for portable SDR DXing and the RSPdx when I wanted make wide bandwidth recordings and venture above VHF frequencies.

Home transceivers

Without a doubt the new Mission RGO One 50 watt HF transceiver got the most air time at home and a great deal of field time as well. It’s such a pleasure to use and is a proper performer to boot!

My new-to-me Icom IC-756 Pro, however, has become my always-connected, always-ready-to-pounce home 100W HF transceiver. It now lives above my computer monitor, so within easy reach. Although it’s capable of 100+ watts out, I rarely take it above 10 watts. The 756 Pro has helped me log hundreds of POTA parks and with it, I snagged a “Clean Sweep” and both bonus stations during the annual 13 Colonies event.

Field transceivers

The new Icom IC-705 has become one of my favorite portable transceivers. Not only is it the most full-featured transceiver I’ve ever owned, but it’s also a brillant SWLing broadcast receiver. With built-in audio recording, it’s a fabulous field radio.

Still, the Elecraft KX2 remains my choice field radio for its portability, versatility and incredibly compact size. This year, in particular, I’ve had a blast pairing the KX2 with the super-portable Elecraft AX1 antenna for quick field activations. I’ve posted a few field reports on QRPer.com and also a real-time video of an impromptu POTA activation with this combo:

How about you?

What radios did use use the most this year and why? Did you purchase a new radio this year? Have you ventured into the closet, dusted off a vintage radio and put it on the air?

Please comment!