Author Archives: Guy Atkins

Discounted New Tecsun PL-310ET Receivers on Amazon

Today I noticed that Amazon is offering an excellent price on the fine performing Tecsun PL-310ET portable AM-FM-SW radio.

The current sale price is $39.80 with free shipping for Amazon Prime members. This is a good price on a compact portable radio normally selling for $48.00.

Besides being a worthy value in a low cost portable, DSP-based radio for the SWL hobbyist, the PL-310ET also excels as a receiver to keep in your vehicle’s glovebox or your emergency kit.

The PL-310ET was included in Gary DeBock’s 2015 Ultralight Radio Shootout Review, and it fared quite well in Gary’s tests.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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Portable Powerhouses: Comparing the Bonito Boni Whip and Wellbrook ALA1530LNP Antennas

One fits in a car (well, most vehicles anyway) and another easily slides into a small daypack; which antenna is best for DXing on-the-go? The ALA1530LNP and Boni Whip are at opposite ends of the portability scale (as well as the price scale).

I’ve written about the ALA1530LNP in the pages of the SWLing Post before, where I compared it against another Wellbrook loop antenna on extremely weak medium wave signals. The ALA1530LNP currently costs $413 USD including shipping to the Seattle USA area where I live.

More recently I’ve been intrigued by UK Oxford Shortwave Log’s (YouTube) excellent videos demonstrating the DXing prowess of the very compact, highly portable Bonito Boni Whip antenna. Through a Bonito USA dealer I was able to purchase the Boni Whip at an attractive $99 USD price (plus $11 shipping).

So, is it fair to compare “apples and oranges”? Maybe not, but it was fun and interesting nonetheless to take both antennas to the countryside to find out how they perform head-to-head in a portable situation. My destination was a small forested campground, in a valley east of this beautiful Mount Rainier, Washington scene:

In mid-July, Tipsoo Lake near Mt. Rainier is still surrounded by snow.

Over the course of three days I compared the two antennas with these receivers:

  • Eton E1XM
  • Sangean ATS-909X
  • Elad FDM-S2

I set up the E1XM and ATS-909X receivers on a portable tote box with the antennas powered by SLA gel cell batteries and using a two-way antenna switch for instant comparisons.

Each antenna was mounted on its own “pro” speaker stand and separated 60 feet from each other. The antennas were connected to receivers by equal 100 foot lengths of RG-58 coax cable, and were over 80 feet away from my laptop computer (the only noise source in the area).

In keeping with the uber-portable theme of the Bonito antenna, I used a very compact 1.2Ah SLA gel cell battery for its power injector (junction box). Since the antenna consumes a mere 45 ma. of current, this small rechargeable battery will power the Boni Whip for many, many hours.

The Wellbrook ALA1530LNP requires a still reasonable 200 ma., and I brought along a much larger battery to power it.

Below are a selection of 30-second medium wave and shortwave recordings, each one of them beginning with the Boni Whip and switching to the ALA1530LNP midway through the recording.

Boni Whip vs ALA1530LNP – E1XM Receiver

660 kHz

870 kHz

1660 kHz

3330 kHz, CHU Canada

4960 kHz, VOA Sao Tome

9535 kHz, R. Algerienne

11600 kHz, Denge Kurdistan

11760 kHz, R. Havana Cuba

EDIT 7/14/2017: 11905 kHz, Reach Beyond Radio, Kununurra WA Australia (tentative; listen for the Aussie-accented weather forecast at the end of the Wellbrook loop portion. This catch was at 03:48 UTC, which matches up with the brief English language broadcast in Reach Beyond’s schedule for 11905 kHz. This catch does not appear to be China National Radio as  I first thought.)

Boni Whip vs ALA1530LNP – Elad FDM-S2

These 30-second videos are from the Elad SDR’s FDM-SW2 software. As above, the first half of each recording is the Bonito antenna followed by the Wellbrook loop. If you maximize the playback of a video to full screen you can read the signal-to-noise ratio (SNR) change (“Delta”) as the antenna is switched to the ALA1530LNP.

The compact Boni Whip is a unique commercial design of “mini whip” antenna, pioneered by Roelof Bakker, PA0RDT some years ago. As with all these compact e-field antennas they can be a significant “noise sponge”, collecting any RFI or interference in the area. This is especially true if the coax shield is not grounded. Despite using two Bryant/Bowers design of RF chokes in series, the Boni Whip’s reception was degraded by RFI emitted from my laptop over 80 feet from the antennas. The RFI was quite a bit worse without any RF chokes in-line. You’ll note though that even the Wellbrook loop received some interference from the laptop on the higher shortwave frequencies.

4840 kHz, WWCR, Nashville TN USA

5985 kHz, R. Taiwan Intl. via WYFR, FL USA

6090 kHz, The Caribbean Beacon, Anguilla (distorted, with transmitter problems)

6100 kHz, R. Havana Cuba

9600 kHz, unidentified station

11725 kHz, R. New Zealand Intl.

11790 kHz, R. France Intl., Issoudun

11840 kHz, R. Havana Cuba (target: Chile)

Observations. On medium wave (E1XM examples) the directionality of the Wellbrook loop could be noted on one, maybe two of the three recordings. This can be a benefit–or not–depending on your goal. (I did not rotate the Wellbrook loop to null or peak any specific MW signals.) The omni-directional Boni Whip would not be the antenna of choice for a hard-core medium wave DXer; however, it is extremely compact and lightweight for camping and travel if you will be DXing or SWLing on shortwave also. The Wellbrook though is highly regarded as a medium wave DX antenna, especially when used with a rotor to take advantage of its sharp broadside nulls.

I didn’t test the Boni Whip on long wave, but Oxford Shortwave Log and others report it does very well on LF. I tried the antenna on FM frequencies against the Eton and Sangean’s telescopic whip antennas but in every case the reception was worse on the Boni Whip.

As I expected on shortwave, the ALA1530LNP greatly outperformed the Boni Whip on some signals. On others, reception was extremely comparable! The 3330 kHz CHU recording surprised me with the neck-and-neck reception. At this tropical band frequency there may have been some directionality to the signal, and the loop may not have been oriented optimally. The 4960 VOA reception was also very close.

I was disappointed, but not surprised at the RFI pickup of the Boni Whip when using my laptop and the Elad SDR receiver. The two RF chokes tamed the spikes and hash a bit, but removal was far from complete. The Wellbrook wasn’t always “clean” in this regard though.

Final notes. I think the Boni Whip is an extremely high value in a “jack of all trades” very portable antenna. Like Oxford Shortwave Log and others, I find this active antenna’s noise level to be extremely low, helping its sensitivity reveal weak DX signals in a surprising fashion. I would not hesitate to use this antenna away from noise sources when traveling with a non-computerized receiver. Well done, Bonito!

Is the Wellbrook ALA1530LNP worth four times the Boni Whip’s USA price? To the serious DXer who has no room for large passive antennas (Beverages, phased delta loops, DKAZ, etc.), the 1-meter diameter Wellbrook is clearly in a class of its own. By the way, the US Dollar to UK Pound ratio has improved in recent months, so the Wellbrook is an improved value for USA radio hobbyists now.

Truly this was an “apples to oranges” comparison, but I thoroughly enjoyed using both models. I welcome your comments, particularly if you also own both of these fine antennas.


Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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New-in-the-Box ICOM IC-R71A and IC-R7000 Communications Receivers Surface on Ebay

Attention: communications receiver collectors! Not one, but two vintage ICOM IC-R series receivers have been listed on Ebay by the same seller. Presumably the same individual owned and stashed away both units, and now they are offered by the Ebay store “Mikes Emporium“.

Both receivers are described as “new in box”, with a variety of photos shown, including the original sales receipt with options listed. A tag on the IC-R71A shows the receiver originated at well-known Virginia retailer Electronic Equipment Bank (EEB). The R71A is of 1988 vintage, per the receipt; the R7000 may likewise be from the same year.

Link for the ICOM IC-R71A: http://www.ebay.com/itm/NEW-IN-BOX-ICOM-IC-R71A-Radio-Communications-Receiver-with-Remote-MORE-W-W-/112397220884

Link for the ICOM IC-R7000: http://www.ebay.com/itm/NEW-IN-BOX-Icom-IC-R7000-VHF-UHF-FM-Radio-Communications-Receiver-with-Remote-/112397200299

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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Pristine Condition Braun T-1000 Receiver Appears on Ebay

The German industrial designer Dieter Rams is world renowned for his beautiful and functional product designs, including the Braun T-1000 portable receiver.

These fine, collectable receivers appear on Ebay regularly, but this one is in pristine shape:

The asking price is a cool $1,800 USD, but for the near mint condition of this T-1000 it is likely appropriate; perhaps the new owner will acquire it for a “Best Offer” price. Other T-1000s on Ebay currently are priced from $370 to $1,299.

Of course, the cost is in-line with a collectable value; functionally, it’s reception abilities are almost certainly surpassed by a modestly priced SDRPlay RSP1 or a vintage Sony ICF-2010 for instance. The radio aficionado interested in the 55 year old T-1000 is not expecting best-in-class reception, but the chance to own a recognized icon of industrial design (the T-1000 is in NYC’s Museum of Modern Art’s permanent collection).

Click here for the Ebay auction of the Braun T-1000: http://www.ebay.com/itm/BRAUN-T1000-GERMAN-GRUNDIG-SATELLIT-LIKE-SW-TRANSISTOR-RADIO-NEAR-MINT-/201891688853

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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30 Year Flashback: From the April 1st Edition of the Cascade Mtn. DX Club Bulletin

Among SWLing Post readers, I’m sure there are others like myself who, decades ago, listened to the Zzzt…Zzzt…Zzzt! sound of a dot-matrix printer as it spit out copy for “pasting up” a DX club bulletin. In the 1980s I was one of those enterprising DXers, taking over publication of the Cascade Mountain DX Club (CMDXC) when a local hobbyist lost interest in producing it.

For a few years I found that creating a regular bulletin was almost as satisfying as DXing itself, and I went on to publish another local bulletin, DX/Northwest. It was a forum for DXers in the Pacific Northwest USA to share loggings and information. I also hosted occasional gatherings of Seattle area DXers who were members of the club.

I recently came across my collection of all the past bulletins and appropriately found the April 1, 1987 edition of the CMDXC. I had completely forgotten I’d made an effort every April 1st to “spice up” the bulletin content with some April Foolery.

The first item was slipped into the midst of the monthly loggings, just to make sure readers were paying attention:

The fictitious DXer named “Grobe” in the spoof logging was a thinly veiled reference to radio hobby publisher Bob Grove of Grove Enterprises and Monitoring Times magazine. He actually wrote to me after the initial April 1st edition, beginning a running joke of humorous responses to my April Fool’s bulletin content, and always signing his letters “Bob Grobe”. I received similar letters from him after each year’s April edition. I don’t recall Bob ever being a member of the CMDXC, so I’m not sure how he knew of the content. I still have one or more of those letters stashed away somewhere.

Perusing the April 1st, 1987 bulletin again, I note that I was feeling charitable towards a certain down-on-his-luck DXer “M.T. Pockitz” from nearby Vancouver, BC Canada, and wanted other club members to help him in his time of need. I was also in close touch with new developments in radio technology, as I am today:

Who else remembers the old DX club bulletins–from the dot-matrix printer era–with fondness? You may even be senior enough to feel nostalgic over the “ditto machine” or Mimeograph produced publications!

To read more humor that only a DXer could love, I highly recommend Don Moore’s excellent web site BLANDX – Historical DX Humor. This site is the web archive of the classic BLANDX parody bulletins. I was an occasional contributor, and on the receiving end of Don’s wonderfully warped funny bone at times. If you can’t laugh at the BLANDX content, watch out–your WPE Callsign might have expired!

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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An EDC Bag for the Classic Sony ICF-SW100 Receiver

In a 2014 article, this site’s administrator Thomas Witherspoon introduced readers to the CIA’s Survival Kit which is housed in a superbly sturdy waistpack, the Maxpedition M-2. Thomas observed that the M-2 pouch is perfectly suited to holding the diminutive Sony ICF-SW100 receiver.

I was intrigued by that possibility, but only recently tried to combine the two after I resurrected another ICF-SW100 that fell silent to the chronic broken ribbon cable problem. Indeed, the radio is a perfect fit and the M-2 is impressively solid and well designed. I was not aware of the Maxpedition firm prior to learning of the M-2 bag, but I see in various forums they are a major player in well-made gear for the survivalist and outdoor enthusiast crowds. The M-2 is a very popular item, and one or more of the four available colors are sometimes out of stock at the manufacturer. Fortunately there are many sellers on Amazon and Ebay who have these waistpacks available.

What is EDC you may ask? It refers to “Every Day Carry”, the essentials that an individual deems necessary for their lifestyle or a particular activity. For me, an EDC bag is taken along on hikes or other outings to the countryside and typically contains a compact shortwave radio and related accessories. It’s always fun to stop for lunch or a break in a remote location and be able to search for interesting stations whenever the mood strikes.

This photo shows what I’m able to carry in the Maxpedition M-2 bag; a coffee mug is shown for size comparison. Contents of the “kit” include:

  • The Sony ICF-SW100 receiver
  • Zero Audio Carbo Tenore In-Ear Monitors & soft pouch
  • Sony AN-71 reel-up antenna
  • Panasonic RR-XS400 Digital Voice Recorder
  • Short 3.5mm male-to-male stereo audio patch cable
  • Two extra AA batteries for the Sony receiver
  • An extra AAA battery for the Panasonic Digital Voice Recorder

A few comments on the contents. The Zero Audio Carbo Tenore In-Ear Monitors (IEMs) provide excellent audio quality for their price. They are among a handful of IEMs regularly recommended by budget-minded audiophiles on the popular Head-fi.org site. I like these IEMs not only for the audio quality, but also their small size (in the cloth bag) which barely fits into the M-2’s main compartment along with the ICF-SW100. Larger earbuds or IEMs might not fit the M-2 without being mangled by the hefty YKK zippers. One caution: the similar Carbo Basso model by Zero Audio is deemed by many to be overly heavy on the bass frequencies. I find the Carbo Tenore to be more than sufficient for bass heavy genres like Electronica.

The Panasonic RR-XS400 digital voice recorder has been out of production a few years, but is a highly capable and compact recorder. It contains a hidden USB plug for charging and data transfer, has a fully featured and backlit LCD display, built-in stereo microphones, switchable LINE/MIC inputs, and other useful features. In excellent used condition the RR-XS400 is worth about $50 USD in 2017, despite some Amazon sellers trying to move them at the original $280 price.

The extra AAA battery for the recorder slips into the front pouch of the M-2 bag along with the Sony AN-71 antenna. The additional AA batteries for the radio, however, are held in the two “pen loops” on the left and right of the M-2. Despite these loops being open-bottomed tubes, the fit is tight enough to hold the batteries securely.

Like every portion of the Maxpedition M-2 bag, the belt loop is proportioned perfectly and sewn with precision. With the Sony ICF-SW100 EDC “kit” secured to my belt on a hike, I’m assured of quick access to a DXing opportunity, such as when hiking the Naches Loop Trail near beautiful Mt. Rainier:

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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A New Approach to FSL Antenna Construction

Introduction

I’m very fortunate to live across town from my good radio hobby pal Gary DeBock. He has been responsible for the rapid growth in Ultralight radio DXing and the construction of Ferrite Sleeve Loop (FSL) antennas. Living near each other as we do, I’ve benefited a lot from his expertise and creativity in the hobby. We’ve enjoyed visiting about Ultralight radios and antennas many times over a leisurely lunch. If you’re unfamiliar with Gary’s efforts, just do a YouTube search on his name and see just a few of the many FSL antenna variations he’s built!

Gary uses PVC tubing, “Fun Noodle” foam cylinders, sections of curved foam, and rubber plumbing adapters almost exclusively as the core supporting structures for his FSLs, from small 3-inch models to 17-inch monsters. Gary certainly has perfected his own techniques with these raw materials; he’s an expert in combining them. He even makes PVC table structures to support his FSLs during Oregon coastal DXpeditions, as seen in some of his YouTube videos.

These materials work well, but over time even FSLs as small as 7 to 8 inches in diameter begin to sag and lose their perfectly circular shape. This seems to be caused by the shifting of individual segments of foam which are wrapped around a “Fun Noodle” core and center PVC tubing.

What possibilities are there for other materials in FSL antenna construction? It would be a fun challenge to build a small to medium sized FSL antenna that would have these qualities:

  • Maintain a circular cross-section without sagging
  • An appearance less like a threatening explosive and more like a commercial product
  • Use alternate construction methods for those not skilled with cutting & gluing PVC tubing

I began to keep my eyes open for likely candidates as I visited hardware stores, department stores, and office supply outlets. Eventually some ideas began to gel.

Raw Materials

Here is a visual and descriptive list of what I used in this alternate design of Ferrite Sleeve Loop antenna. I won’t go into great detail about dimensions, quantities, and measurements, as other DIYers should be able to easily follow the general idea presented here. This article is mainly to get you thinking about other ways to construct a ferrite sleeve loop antenna.

The Core of the Matter

This 18-inch long, semi-rigid foam roller is six inches in diameter. It’s a workout and exercise aid which I found in the sports department of my local Walmart store. The cost was approximately $13. This one-piece foam is a perfect foundation for holding and protecting the fragile ferrite rods and keeping them in a circular arrangement; since the roller is in one piece there is nothing to shift around, or sag. When placed on this core, the final diameter of the FSL antenna is approximately seven inches.

So, what to put the antenna in? Something needs to suspend and protect the antenna as a substitute for the PVC frame previously used. This Sterilite tote box is the perfect size to hold the antenna. As shown in the photo, the dimensions are approximately 14-1/4″ X 9-5/8″ X 12-1/4″; the model number is 1896.

Early on, I decided that the flimsy “locking tabs” on the cover would not suffice for holding the relatively heavy antenna when carrying the tote by the handle. I drilled holes and attached a dozen small Nylon nuts and bolts to secure the cover. (Nylon avoids distorting the medium wave reception pattern of signals, as metal hardware could.)

An ample quantity of 200mm ferrite rods are needed, plus a air variable capacitor (preferably with a 8:1 reduction drive shaft), and Litz wire. 1162 strands/46 ga. Litz provides the most sensitivity but the coil will cover a greater width on the rods.

Gary likes to use waterproof medical tape, sticky side out, to hold the rods in place, but I like to use Gorilla brand tape, as it is extremely sticky and holds the rods better. My choice for the rod-to-coil spacing  material is two turns of 1/8″ thick bubble wrap.

This is the foam core, ferrite rods, bubble spacer, and coil assembly prior to fitting in the Sterilite tote container. Before assembly to this point you’ll need to cut the foam roller to length using a serrated knife or electric carving knife. Two sturdy cable ties help hold all of the rods in place. A better alternative might be strips of 1/2″ wide Velcro straps purchased from a fabric shop or home improvement store.

Another key item to this construction method is the use of plastic drywall anchor screws. These are meant to be pushed and screwed into gypsum wallboard for sturdy attachment of bolts or picture hangers on walls. When screwed through drilled holes in the side of the Sterilite tote, they secure and suspend the foam roller/ferrite sleeve loop assembly. The density of the foam roller is sufficient to give a good grip to the drywall anchors. Eight to ten anchors per side are enough to hold the assembly in place. See the photo at the beginning of this article for a good view of this mounting method.

Every good FSL antenna design needs an official sounding manufacturer! With tongue firmly in cheek I’ve appropriated the name shown on this self-produced label. Clearly, a Ferrite Sleeve Loop antenna from Naughtabaum Ferrite Specialties Ltd. stands a better chance than most of passing through TSA checkpoints, right?

I hope this article has given you some new ideas for FSL antenna designs. There’s certainly room for improvement, including making the antenna’s ferrite rods look less intimidating…less like a bundle of dynamite! Perhaps the entire assembly can be wrapped with something that shields the rods from view, or you could use an opaque tote container rather than a clear model.

Be on the lookout for useful materials to repurpose. Trips to your local home improvement stores, office supply, and other outlets will give you further ideas on how to design your own Ferrite Sleeve Loop antenna.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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