Category Archives: New Products

WRTH 2017: A look inside

I received my copy of the 2017 World Radio and TV Handbook (WRTH) directly from the publisher last week, just prior to Christmas holiday ravels. As I mention every year, I look forward to receiving this excellent staple radio reference guide–and this is their 71st edition!

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, WRTH’s International Editor, Sean Gilbert, tells us what sparked his interested in the hobby and what lead to his career with WRTH which started in 2000.

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

This year, WRTH begins with a review of the Icom IC-7300 general coverage transceiver. They also review the Reuter Elektronik RDR55D, and re-visit the SDRplay RSP1. Following radio reviews, they evaluate the excellent Wellbrook ALA1530LNP magnetic loop antenna and the Bonito AAS300 3 way active RF splitter.

The following article focuses on one of my favorite shortwave broadcasters, The Mighty KBC. WRTH contributor, Max van Arnhem traces the broadcaster’s history and gives us a little insight about the people behind this music powerhouse. If you’re a KBC fan, you’re in for a treat!

I was very happy to find that the following feature article explores the world of Remote Reception. No doubt, remote listening is becoming one the most accessible ways many of us discover and enjoy our hobby today–especially as it can be difficult for some of us to fight urban radio interference.

Following this, WRTH writer, Hans Johnson, features an article on CKZN St. John’s Newfoundland. In this short article, Johnson covers the history and mission of this shortwave relay, dating back to the days when Newfoundland was a British dominion. Looking forward, Johnson notes that the CBC intend to not only continue this service directed at Labrador’s most remote areas, but it intends to replace their 1 kW Elcom Bauer transmitter in the coming years. This pleases me to no end as I’ve always loved snagging this particular relay of CFGB from my home here in North Carolina.

Next, DXer Rob Shepard writes about his travels in South America and the Pacific. Being an avid traveller myself, I love reading about others’ adventures across the globe with radio. Shepard even notes some catches from the Queen Mary II. I’ve never had the chance to do DXing while maritime mobile, but I hope to someday.

The following article features Danish radio enthusiast, Vagn Fentz, who has collaborated with WRTH since one of its very first editions. His radio history starts back when he was a schoolboy in Denmark during WWII, listening to the radio in secret. His story gives us insight into both his own world and that of the WRTH over the years.

Next, Michael Pütz outlines the progress, so far, of setting up an HF disaster relief radio network: the IRDR Project. If you haven’t heard of the IRDR project, this article makes for a great primer and also speaks to the potential future of a radio network that could have major positive impact over vast regions in the wake of disaster.

The final article–a tradition–is the WRTH HF propagation report/forecast by Ulf-Peter Hoppe. Always an informative read (despite the fact we’re heading into a solar minimum).

The 71st is another fantastic edition of the World Radio TV Handbook. I’ve never been disappointed with WRTH, in truth. 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 2017 directly from WRTH’s publishers, or from a distributor like Universal Radio (US) and Amazon.com (US), Radio HF (Canada), or BookDepository.com (International).

Updates to the Morse Pad app

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Many thanks to Chris Smolinski, who shares the following update:

I have a new version of Morse Pad for the iPad/iPhone/iPod Touch.

This update includes an improved decoder which better handles improper dot / dash / space timing by the sender (poor fist), automatic speed (WPM) algorithm, and adds AFC (Automatic Frequency Control), which auto tunes in the strongest signal present.

App Store Link: https://itunes.apple.com/us/app/morse-pad/id385629886?mt=8

Mechanically Based Antenna: Underwater and underground radio

Reviews of the Elpa ER-C57WR shortwave portable?

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I recently received an email from SWLing Post reader, Ibrahima Ditinn Diallo, regarding a receiver I had never heard of–the Elpa ER-C57WR. Ibrahima has been searching for a new receiver and is considering the Elpa.

I did a quick search and discovered that the Elpa ER-C57WR is available from a number of sellers on eBay–as both new and used for around $63 US shipped from China.

The form factor is very similar to the C.Crane CC Skywave, but it apparently lacks some of the Skywave’s functionality like weather radio and (perhaps?) multiple AM bandwidths. Here’s the ER-C57WR spec sheet:

Remembering a post from a couple years ago, I quickly realized the ER-C57WR is almost an identical match to the DigiTech AR-1733 available via Jaycar in Australia.

If the ER-C57WR is simply the same receiver as the AR-1733, I would be hesitant to recommend it. Many AR-1733 owners complained of lousy AGC performance.

Of course, it’s been a couple of years since the introduction of the AR-1733–perhaps this Elpa-badged version has been updgraded?

I’m curious if any SWLing Post readers have purchased the Elpa ER-C57WR and could comment about the receiver’s performance.

Click here to search eBay for the Elpa ER-C57WR.

NPR: “almost certainly, the tiniest radio receiver in the world”

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(Source: NPR)

Physicists at Harvard have built a radio receiver out of building blocks the size of two atoms. It is, almost certainly, the tiniest radio receiver in the world.

And since it’s a radio, it can play whatever you want to send its way, including Christmas music, as this video by the Harvard team that designed it makes clear:

Click here to view on YouTube.

NPR then quotes from The Harvard Gazette where Leah Burrows, of Harvard’s John A. Paulson School of Engineering and Applied Sciences, explains how the tiny radio works:

Radios have five basic components: a power source, a receiver, a transducer to convert the high-frequency electromagnetic signal in the air to a low-frequency current, a tuner, and a speaker or headphones to convert the current to sound.

In the Harvard device, electrons in diamond NV centers are powered, or pumped, by green light emitted from a laser. These electrons are sensitive to electromagnetic fields, including the waves used in FM radio. When NV center receives radio waves. it converts them and emits the audio signal as red light. A common photodiode converts that light into a current, which is then converted to sound through a simple speaker or headphone.

An electromagnet creates a strong magnetic field around the diamond, which can be used to change the radio station, tuning the receiving frequency of the NV centers.

Shao and Lon?ar used billions of NV centers to boost the signal, but the radio works with a single NV center, emitting one photon at a time, rather than a stream of light.

The radio is extremely resilient, thanks to the inherent strength of diamond. The team successfully played music at 350 degrees Celsius — about 660 Fahrenheit.[…]

Click here to read the full article on NPR’s website.

Troy reviews the Audiomax SRW-710S

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Many thanks to SWLing Post contributor, Troy Riedel, for the following guest post:

A Mini-Review of the Audiomax SRW-710S

by Troy Riedel

Why would someone want a sub-$20 shortwave radio? Wait … I guess I should be answering questions & not asking them, right? But I’ll give you my answer to “why I want a sub-$20 shortwave radio”: I have many nice radios, but I wanted one that I consider “disposable”. I define “disposable” as something I won’t be upset if I lose, get it splattered with paint, or leave it outside only to get rained on. Taking the family of four to the movies nowadays costs upwards of $100 (the three ladies I live with can really throw-down pop & popcorn!) so a sub-$20 radio, even a “disposable one”, is a true bargain.

I have seen the SRW-710S badged under three different names: Audiomax, VITE and TIVDIO. There very well may be other badging. I paid $18.52 for my Audiomax badged device direct from a vendor in China. I’ve subsequently seen it as low as $13 on eBay and as much as $37 on Amazon. So much for a sub-$20 radio, huh?

The SRW-710S comes with only a USB charging cable in the box to recharge the Li-ion BL-5C battery (no earbuds, no case or pouch – just a very simple set of basic instructions). The 710S features a small LCD screen that offers menus in three languages: English, Spanish & Chinese.

The screen greets you with “welcome” (lowercase) when turning it on & “Bye Bye!” when you power-off. There is a Sleep Timer function that I have yet to use. All of the ports are on the right side of the unit (nothing on the left). It has a TF Flashcard Slot – no card provided – for recording off the radio & for playing pre-loaded mp3 & wma files from the flashcard.

It has 100 memories, a Line-In port, a built-in mic, and a headphone port. There is no ANT-In port. This radio has AM, FM & SW (no LW) with the appropriate international tuning steps. Lastly, there is no folding stand on the back (one is provided and is attached to the wrist strap – it is inserted into a small slot just above the battery cover).

One Chinese web site listed the SRW-710S as having an “AKC6951 DSP chip”. Until now, I had never heard of this DSP chip and I frankly know nothing about it. Maybe some more informed readers can comment?

Operation is easy (except for one quirk that I will detail later). There are two rows of numbers for direct input of a frequency. Simply input the frequency … and then wait (there is an approximate 3-5 second delay from input to the radio actually tuning to the frequency … I am still getting used to this pregnant pause). You also have an option of tuning directly to a meter-band.

Of course, there is no SSB for this low price.

The one speaker is a bit “tinny” but adequate (stereo via user-supplied earbuds). And considering the price point, the RF shielding isn’t too bad. I can actually use the shortwave band of this radio in my kitchen and breakfast nook (I cannot say that for my more expensive receivers).

The biggest limiting factor in reception is the size of the telescopic antenna (15.5”). However, for its size I am quite impressed (it’s exponentially better than the old Grundig G2000A Porsche that has a 21.25” antenna – but that radio is notorious as needing a reel antenna). Just via the telescopic whip, I can actually tune the major broadcasters to NA (e.g., Radio Romania), I can adequately tune to the VOA 15.580 MHz signal to Africa during the North American East Coast AFTN, and the time signals are easily audible (of course, frequency appropriate for the time of day).

I do not plan to open the radio’s chassis, but AM reception seems to be limited due to the obvious small size of the ferrite antenna (the radio itself is essentially palm-sized, approximately 4.75” x 3” & less than 1” thick). My postal scale indicates it weighs 5.5 – 6 ounces including the battery. The radio must be propped to support it when attaching the telescoping whip to a Slinky Antenna (even the weight of the Slinky’s alligator clip causes balance problems)
One quirk I have found: there is a “Lock” key. However, it only seems to lock the radio power “on” (locks are used to lock the power “off” during transport so the power remains off and the battery doesn’t drain). The “Lock” feature is not discussed in the instructions and at present I have not figured-out if this switch works in the traditional way. I find this to be quite amusing because it’s either an odd quirk or I’m just not smart enough to intuitively figure it out.

I am quite satisfied with my new “disposable” $18.52 Shortwave Radio (I have no information whether the quality I have considered is consistent through a production run or between badging). For those who wish to listen to a local AM or FM station – or listen to one of the “major” shortwave broadcasters with a booming signal into your part of the world – you can’t beat it for this price point. I can see myself using this radio while I complete outdoor household repairs or while cleaning-up the garage. Too bad it’s so close to Christmas, this would make a great stocking stuffer to introduce someone, young or old, to the world of shortwave.

Update: Searching for the SRW-710S

Note that the lowest prices omit the model number in eBay search results.

Click this link to search eBay for the SRW-710S on eBay.

Scroll through search results to find a matching receiver.

Thank you, Troy, for mini-review of the SRW-710S! Like you, I have very low expectations from shortwave portables at this price point. Still…for the glove compartment of your vehicle, for outdoor listening, for small gifts? These fit the bill! I’m most impressed you could receive the number of stations you did from inside your home.