Category Archives: Radios

Wired.com reviews the Como Audio Solo

como-audio-solo-tableMany thanks to SWLing Post contributor, Jeff McMahon, who shares this review of the Como Audio Solo:

Here’s a $300 internet radio review from Wired:

https://www.wired.com/2016/12/review-como-audio-solo/

Click here to view on Wired.com.

I was an early backer of the Como Audio Solo and reviewed it in October.

Since then, the Solo has become my WiFi radio of choice. I have it hooked up to an SSTRAN AM transmitter and use it to pipe audio through my whole house via the AM broadcast band. Though this only concerns a tiny fraction of hard-core radio geeks: the Solo has a very quiet power supply and my AM transmitter picks up no hum from the Solo. All of my other WiFi radio induce a hum if connected to mains power. This is what makes the Solo so useful in my household and shack.

Of course, when I have it tuned to a music station, like RFI Musique, its built-in speaker system provides ample fidelity!

As I mention in my review, FM analog reception is mediocre, though I imagine it would improve with an external antenna.  Wired believes the Solo is good, but not great.

Mr. Carlson restores and repairs a Hammarlund HQ-140-X

hammarlund-hq-140xMany thanks to SWLing Post contributor, Moshe, who writes:

Hi Thomas!
You must see this restoration job from Mr. Carlson’s lab:

Click here to view on YouTube.

Thank you for sharing this video, Moshe!  I truly enjoy watching Paul’s videos–no doubt, any radio turned over to him is in expert hands. I love how he explains, in such detail, each action he takes to restore and repair these vintage radios.

Click here to view Mr. Carlson’s YouTube channel.

Trying to chose between the CC Skywave and Tecsun PL-310ET?

CC-Skywave-And-Tecsun-PL-310ET-SideMany thanks to SWLing Post reader, Joe, who recently asked in our comments section:

“The CC Skywave is more than double the price of the Tecsun PL-310ET. The two radios appear to have similar features and performance. Can anyone suggest a reason why one would want to pay the extra charge for a Skywave?”

Thanks for your question, Joe. I’m asked this a lot by SWLing Post readers, so quickly realized I should just turn my response into a proper post.  Here’s my response in a nutshell:

Tecsun PL-310ET

The Tecun PL-310ET

The Tecsun PL-310ET is (and has been for years) one of the best budget shortwave portables out there.

For the price of $40-45 US shipped (via eBay, for example), you really can’t go wrong.  It’s certainly a benchmark among the ultralight DSP portables.

The ($79-89 US) CC Skywave, in my opinion, has a few advantages:

  1. An excellent weather radio receiver (for folks in North America)
  2. The AIR band which is a fun and useful addition if you live near an airport or like travelling by air
  3. I prefer the Skywave over the PL-310ET on the mediumwave band. Its selectivity and AGC, in my opinion, have a distinct edge over the ‘310ET for MW DXing.

Because of these particular advantages, the Skywave has become my travel portable of choice when SSB reception isn’t a priority.

The CC Skywave

The CC Skywave

You might check out my CC Skywave review because I tried to include reception recordings which I felt represented both radios fairly:

https://swling.com/blog/2014/12/review-of-the-c-crane-cc-skywave-portable-radio/

In short, though? If I didn’t care about the AIR band or NOAA weather radio, I’d be quite happy with the PL-310ET. In truth, you really can’t go wrong either choice.

I can say that I now take my CC Skywave on travels more than my PL-310ET.

Click here to search for the Tecun PL-310ET on:

Click here to search for the CC Skywave at

  • C.Crane ($89.99 and free shipping through Dec 6, 2016)
  • Amazon.com ($89.99 with free shipping option)
  • Universal Radio (lowest price without shipping: $79.95)
  • eBay (pricing varies greatly)

Either of these radios, by the way, would make for an excellent gift.

 

A review of the Elecraft KX2 general coverage QRP transceiver

The following review first appeared in the November 2016 issue of The Spectrum Monitor magazine.


elecrat-kx2-review

The Elecraft KX2 tuned to Radio Australia.

It’s not every day that I get exciting news about the production of a new radio.

It was two days before the 2016 Dayton Hamvention–the day before the Four Days in May QRP conference–as I was eating lunch en route to Ohio, that I received the news: Elecraft had just announced a new transceiver, the Elecraft KX2.

Elecraft being known for their exceptional products, I thought instantly, hmmmm, this could be interesting.  I immediately dropped everything and contacted Elecraft, asking, “When can I see this new rig?”

Wayne Burdick (N6KR) of Elecraft kindly sent me a few specs, and the following day, I previewed the KX2.

What is the KX2?

In short: the KX2 is a feature-rich pocket QRP transceiver. For those who are familiar with the Elecraft product line, it’s like a KX3 (feature rich portable rig) in a KX1-sized (much smaller, handheld/pocket) package.

The Elecraft KX2 (left) and KX1 (right)

The Elecraft KX2 (left) and KX1 (right)

The day before the Dayton Hamvention, Elecraft allowed me to snap some photos, ask some questions, and generally give their new little rig a once-over.  After holding their new offering in my hand–it’s slightly narrower, if a bit thicker, than a paperback book–was already tempted to plunk down $749 for the KX2 right then and there.

Comparing the size of the Elecraft KX3 (top) and KX2 (bottom) at Elecraft's Dayton Hamvention booth.

Comparing the size of the Elecraft KX3 (top) and KX2 (bottom) at Elecraft’s Dayton Hamvention booth.

So, what what stopped me? For one, I was less than two weeks away from taking a two month trip in Canada, and already had an (embarrassingly) large number of radios to take along. I also had a few other reviews in the works and needed to finish them prior to evaluating the KX2.  And–let’s face it–that kind of cash is significant to a reviewer like me.

Yet there was another consideration–two, actually: I already own both the KX1 and KX3 transceivers, and like them very well. Come on,  I chastised myself, as I continued to admire the latest Elecraft in its tiny package. Wouldn’t a KX2 be rather…redundant?

Nonetheless, in August I took the plunge and ordered a KX2. Perhaps it was a leap of faith…or a momentary lapse of judgement that led me down temptation lane. At any rate, I had been doing enough NPOTA activations that I fell for the idea that I could potentially have the advantages and performance of the KX3 in an even smaller, even more portable, package.

Would there be buyer’s remorse? The only way to tell, obviously, was to put the KX2 on the air.

Learning my way around the KX2

I imagine a lot of new KX2 owners will be Elecraft veterans like myself. Once you’ve used Elecraft equipment for a while, you begin to understand how the company designs their menu trees and functions. In other words, once you’ve experienced the Elecraft ecosystem, moving from one radio to another becomes easier.

The KX2's on-board microphone is located on the left side of the front panel and works very effectively especially in an HT configuration.

The KX2’s on-board microphone is located on the left side of the front panel and works very effectively especially in an HT configuration.

I approached the KX2 with confidence, having owned the similar KX3 for three years and the K2, K1 and KX1 for many years.

 The left side of the KX2 is where all connections are located, save the antenna connector.

The left side of the KX2 is where all connections are located, save the antenna connector.

The BNC antenna jack is located on the right side of the KX2.

The BNC antenna jack is located on the right side of the KX2.

I plugged the KX2 into my power supply, main antenna, and powered it up by pressing the Rate and A/B buttons simultaneously (a clever keylock method). The KX2 defaulted to the 20-meter band. I started tuning around and quickly realized that the SSB mode was set to the lower instead of the upper sideband. No problem, I thought, and instinctively pressed and held the MODE button to switch from LSB to USB. This is where I found the first difference between KX2 and KX3 functions. Pressing and holding mode button on the KX3 toggles USB/LSB, but on the KX2 it enters the frequency memory store mode.

I tinkered with the KX2 MODE button to no avail, so reached for the KX2 owner’s manual, fortunately a well-written tome. Turns out, to switch between USB/LSB, you:  enter the KX2 menu system, select the ALT MD entry, then switch the “alternate” to the “normal” SSB band mode, which moves it to USB on the 20-meter band.

A number of functions accessed on the front panel of the KX3 require using the menu system on the KX2. RF Gain is another example of this, as I discovered pretty quickly.

This got me thinking.  I don’t envy the folks at Elecraft who have to sort out the ergonomics and functionality on a radio as small as the KX2. I decided I’d better check out the owner’s manual and familiarize myself with the functions I use the most in the field.

Elecraft manuals are superb; they're spiral bound, easy to read and comprehensive.

Elecraft manuals are superb; they’re spiral bound, easy to read and comprehensive.

I must say, Elecraft has done an admirable job of keeping the most essential functions on the face of the radio and tucking the less-used functions into the background of their menu system [Not to suggest access is ever complicated, considering that you just 1) enter the menu, 2) select the function, and 3) change the parameter…that’s it.]  No doubt, the reason for their success is the fact that their key designers, like co-founder, Wayne Burdick (N6KR), actually operate radio in the field–they get it.

Speaking of the field, that’s exactly where I wanted to take the KX2 to test, since that’s clearly where the rig’s designed for use. Note here that this is not a base rig: its size and features lends itself very well to a pack radio–one I wanted to keep packed and at-the-ready!

Packing up…

Prior to receiving the KX2, of course, I did some pack research (those of you who know me know that I’m a bit of a pack geek).

Elecraft was actually selling two models of a LowePro pack that fit the KX2 exactly: the ViewPoint CS 40 and ViewPoint CS 60. Though I searched far and wide, I couldn’t find a pack from some of my favorite manufacturers (such as Spec-Ops Brand, Red Oxx, and Tom Bihn) that has the right amount of padding, exact space and fit for the KX2, as did the CS 40 and CS60. So I purchased the larger CS 60–the larger of the two packs.

kx2-lowe-cs60-bag

My Elecraft KX2 kit then consisted of the following:

  • The Elecraft KX2, with internal battery and ATU options
  • An LnR Precision EFT Trail-Friendly antenna (purchased at the Dayton Hamvention)
  • An assortment of relevant connectors and adapters
  • An Elecraft hand mic, borrowed from my KX3
  • A CW paddle (the KXPD2)

All of this–save  fishing line, weight, six-foot coax cable and clipboard–were protected by the compact and perfectly portable LowePro ViewPoint CS 60 padded case, and fit it like a glove. I tucked the whole kit quite conveniently into my 20-year-old Dana Design lumbar pack.

The only way to know if the kit was complete, was to take it to the field. Nothing like trial by fire.

NPOTA: National Parks On The Air

Elecraft-KX2-Clipboard-NPOTA

My first NPOTA activation with the KX2 field kit was at the Carl Sandburg Home in East Flat Rock, NC.

After hiking about twenty minutes to my trail location and setting up the station, which I found to be a fairly simple process, I realized that the KX2 is so compact that it easily fit on the clipboard I was using to hold my log sheets. Thus, the clipboard instantly became my laptop operating table.

As soon as I sat down in my folding chair, I turned on the KX2, set the frequency to 14,286 kHz, and pressed the ATU button, which gave me a 1:1 match (since the EFT is resonant).

Next, I recorded my CQ call into the KX2’s built-in voice keyer by:

  1. pressing and holding the MSG button,
  2. assigning the voice message to “memory allocation 1” by pressing the PRE (1) button,
  3. pressing XMIT to start the recording,
  4. reading off my CQ call, thus: “CQ, CQ, CQ, this is K4SWL calling CQ for National Parks on the Air…”, and
  5. pressing XMIT again to stop the recording.

Then, I started calling CQ by simply pressing the MSG button and selecting my message stored in memory allocation 1 by pressing and holding the PRE (1) button.

By pressing and holding the PRE (1) button, I initiated a loop-playback of my CQ call where my KX2 would transmit my call from memory.  Then I waited a few seconds to listen for any replies, and played it again. (In loop-playback mode, I’d learned that the KX2 will repeat my CQ call until I interrupt it by pressing a button or keying my mic.)

It’s a brilliant and easy function which saves my voice. By automatically calling CQ, it  gives me an opportunity to answer questions from curious passersby who were naturally fascinated by a guy sitting on the side of a trail, talking into a little box connected to a tree-branch suspended wire.

In the end, I didn’t even need to use the voice keyer that much. I worked my minimum of ten stations within six minutes! Of course, I continued to call CQ until I worked everyone in the pile-up (including stations from California, Nebraska, Kansas, Texas, and Mexico–thanks, folks!).

Result?  Wow.  That first field experience at the Carl Sandburg home couldn’t have gone better. And the KX2 had quite a lot to do with that outcome–both in function and form-factor.

Since then, I have taken the KX2 on more than twenty NPOTA field activations, and my compact field kit is making impromptu activations a breeze. Indeed, by the time you read this review, I’m guessing I’ll have added a dozen more NPOTA activations with the KX2 field kit.

[Update: At time of posting this review, I have a total of 54 NPOTA activations–almost forty have been made with the KX2.]

Internal battery option

Activating PK01 (The Appalachian Trail) with the KX2

Activating PK01 (The Appalachian Trail) with the KX2

One of the things that make the KX2 so easy to set up is the fact it can run quite effectively on a high-capacity internal LiPo battery pack.

kx2-battery

The KX2’s 10.8V 2600 mAh LiPo battery

On one particular set of activations, while returning from the W4DXCC conference in late September, I activated several sites, including a couple of “two-fer” sites, just during my drive home. I only used the KX2’s built-in battery to power the rig. I was on the air almost three full hours of fairly intense transmitter use (repeating my CQ call through the voice keyer). The KX2 was able to pump out a full 10 watts of power for a little over one hour, then as the voltage dropped, it reduced output to 5 watts.

I feel like this is impressive performance from such a small battery pack. It’s a little pricey (at $84.90 US for both the battery and external charger), but very much worth the cost if you’re splurging for a KX2, anyway.

View of the Elecraft KX2 battery compartment. Note the speaker wires which attach the two halves of the chassis.

View of the Elecraft KX2 battery compartment. Note the speaker wires which attach the two halves of the chassis.

One complaint: I’m not crazy about the fact that the LiPo battery must be removed from the KX2 in order to be charged. To gain access to the battery, you loosen the two thumb nuts on either side of the KX2, then carefully open the back compartment. You must be careful because two speaker wires are attached to the back panel which holds the internal speaker; if you yank it open, you could disconnect the speaker.

I’ve read a report from an NPOTA activator who said that, in the process of multiple openings/closings of the back plate, the speaker wires have rubbed bare spots on the insulation. He used black electrical tape to fix the problem. So far, I haven’t noticed this, but I certainly see how it could happen with time.

Operating a NPOTA "two-fer" under the Blue Ridge Parkway and in the Great Smoky Mountains National Park.

Operating a NPOTA “two-fer” under the Blue Ridge Parkway and in the Great Smoky Mountains National Park.

In the end, I give Elecraft a little grace on this point. After all, this is the first transceiver they’ve ever produced that doesn’t have a kit form, plus they’re trying to satisfy the needs of battery and charging circuit while keeping costs down, as well as make everything fit in an almost paperback-sized enclosure.  Frankly, this works fine.  I don’t mind the extra care required because, in the end, having such a capable internal battery outweighs any inconvenience of charging at home.

Elecraft, if there’s a way to reinforce the speaker wires, that would likely help.

KXAT2 Internal ATU Option

I ordered the KXAT2 internal ATU option with my KX2. Having used the KX3 internal tuner for years, I guessed this might be an excellent ATU, as well.

And it is. In the field, I’ve used a variety of wire antennas, and the KX2’s internal ATU has matched them beautifully.

So, exactly how good is the KXAT2? The following story will give you an idea.

I brought my KX2 along to the W4DXCC conference in late September. The conference has a club station that consists of two Icom IC-7300s which are hooked up to a variety of antennas. During the conference, my buddy WD8RIF was activating a particularly rare NPOTA site. My only chance of working him was on 40 meters.

Conference attendees took turns operating the KX2.

Conference attendees took turns operating the KX2.

Unfortunately, out of all of the self-supporting antennas erected on site, none were resonant below the 20 meter band. I had no means to properly hang my 10/20/40 meter EFT Trail-Friendly antenna at the hotel, so out of desperation, I tried to load a 20 meter hex beam on 40 meters at QRP power using the IC-7300 and its internal tuner. In short, the IC-7300’s ATU couldn’t find a match and refused to transmit.

But I had my KX2 in my field pack. I set up the KX2, connected it to the 20M hex beam, tuned it to 40 meters, and hit the ATU button.  The KXAT2 promptly found a 1:1 match!

Using the Elecraft KX2 on 40 meters at the W4DXCC conference while attached to a 20 meter hex beam.

Using the Elecraft KX2 on 40 meters at the W4DXCC conference while attached to a 20 meter hex beam.

Granted, we were only operating 10 watts, but even the IC-7300’s internal ATU wouldn’t work at that same power level.

In short, if you plan to operate portable with the KX2, do yourself a favor and order the KXAT2 internal tuner, as well. Clearly, it’s ability to match is impressive.

KXPD2 keyer paddle option

Elecraft also sells a small, attachable paddle that is custom-made for the KX2–it’s called the KXPD2 keyer paddle.

elecraft-kx2-kxpd2-paddles

I had not planned on acquiring a KXPD2 as I’m not the biggest fan of paddles that are attached directly to radios. I did, however, think back to my KX1 and the many times I operated CW while holding that little rig in my hands. To be clear, though, the KX1 paddles are primitive in comparison to the KXPD2, which has adjustable contact spacing and even built-in allen wrench storage.

One night at my local radio club, I passed the KX2 around with the KXPD2 attached and received a number of positive comments about it. I find it a pleasure to use, too, and lightyears better than my KX1 paddle.

In the field, I personally find the two thumb screws which attach the KXPD2 a little small to turn fluidly. This is due, primarily, to the fact I have bigger fingers. Steve (WG0AT) experienced the same problem, and came up with a creative solution: silicone rubber tape. He simply wrapped the tape around the thumb screws, giving them a larger tactile surface area. I’ll try this with my KXPD2 paddle screws, as well.

The KXPD2 is a brilliant little key, I must admit. I say this even though I feel the $109.95 price is rather high. Still: it’s a quality little product and I’ve been very pleased with its smooth action and precision. And, oh, yeah–a bonus–it will fit my KX3 as well!

General coverage receiver

In August, Elecraft pushed out a Beta firmware release on the KX2 which included AM mode. Following this release, I received a number of inquiries from SWLing Post readers asking for a comparison and audio samples.

Elecraft-KX2-Voice-Of-Greece-AM-Mode

At the time, I had the excellent LnR Precision LD-11 transceiver in the shack, so I thought I’d do a quick audio comparison with the KX2 since both price points are similar and both are transceivers with AM mode.

I set the LD-11 to a bandwidth of 9.6 kHz, and the KX2 to 5 kHz: the widest AM filter settings of each. Keep in mind, of course, that this is was not an apples-to-apples comparison, but it did showcase each radio’s potential AM audio fidelity.

To make the playing field as even as possible for these two disparate units, I tuned both rigs to the Voice of Greece on 9420 kHz around 00:30 UTC. VOG’s signal was strong into North America.

I made the following recordings with my Zoom H2N digital recorder, feeding in-line audio patched from each radio’s headphone jack. I tried to balance the audio levels between the two rigs as closely as possible to one another.

The LNR Precision LD-11

LNR-Precision-LD-11-AM-Mode-Voice-Of-Greece

Audio Player

Click here to download the audio.

The Elecraft KX2

Elecraft-KX2-Voice-Of-Greece-AM-Mode

Audio Player

Click here to download the audio.

The Elecraft KX2 in “Delay” audio mode

Elecraft-KX2-Delay-Audio-AM-Mode

Audio Player

Click here to download the audio.

The results from both radios are duly impressive. Since the LD-11’s bandwidth can be widened to 9.6 kHz, strong signals like this one sound pretty darn amazing. In truth, I actually prefer a filter width of about 8.2 kHz on strong signals, but VOG was wide enough to justify 9.6 kHz.  I believe the LD-11 would rival many dedicated tabletop receivers.

The Elecraft KX2, in normal audio mode, sounds flatter and narrower than the LD-11 of course, but still remarkably pleasant–a surprise, considering its limitations.

In the KX2’s “delay” DSP audio mode–available when headphones are used–the signal sounds much wider than 5 kHz, though the effect adds a little graininess to the audio. That’s okay, however; I appreciate having the “delay” audio option in my tool bag.

In the past several months, I’ve used the KX2 for shortwave broadcast listening, and each time I’ve been happy with it. It’s an exceptionally sensitive and selective receiver, with a stable AGC, thus would please the most dedicated DXer. Does it have the audio fidelity of the Drake R8B? No way. But its audio is very good, nonetheless, and it can dig weak DX out of the noise as well as any of my dedicated receivers.

After all, this is a ham radio transceiver, not a broadcast receiver, so I’m impressed that it can double as both.

Mediumwave reception?

While HF reception is very good, Elecraft is the first to tell you that KX2 mediumwave reception is strictly limited, and indeed rather poor:

“Sensitivity rolls off significantly below 3.0 MHz due to protective high-pass filtering. Preamp-on MDS is typically -105 dBm at 1.5 MHz, and -80 dBm at 1.0 MHz, sufficient for emergency AM broadcast signal copy.”

So, don’t plan on doing any mediumwave DXing with the KX2. It is sensitive enough, however, that I can receive strong local stations reasonably well.

Summary

elecraft-kx2-white-bkgrnd

Every radio has its pros and cons. When I begin a review of a radio, I take notes from the very beginning so that I don’t forget my initial impressions and observations. Here’s the KX2’s list, from the first moments I turned it on, to the present:

Pros:

  • Excellent sensitivity and selectivity
  • All modes: SSB, AM, CW, and Data (with built-in PSK/TTY decode/encode)
  • A convenient portable package for the field with needed options:
    • Built-in ATU option
    • Optional internal LiPo battery (see con)
    • With telescopic whip, the KX2 can be used as an HT via the internal microphone
    • Very quick deployment in the field
    • Built-in voice and CW keyer
  • Excellent general coverage receiver; AM mode effective for shortwave broadcast listening
  • Backlit display is easy to read in both shack and field
  • Numeric keypad for direct frequency entry
  • Considerate use of multi-function controls
  • Free and easy firmware updates via supplied software
  • Elecraft support and customer service

Cons:

  • Battery must be removed to charge; battery removal requires careful consideration of speaker wires (see pro)
  • Downward-facing speaker not ideal in the field unless back leg is used to raise off of surface
  • Price (shipped) exceeds $1,000 when loaded with ATU, battery, and external charger
  • Poor mediumwave/AM broadcast band reception (con) by design (pro)

Let’s be frank here: the cons I’ve listed above are rather nitpicky.

I suspect Elecraft will work on a better solution for the speaker wire (for those of us using the internal battery) or else KX2 users will come up with a creative modification.

In a perfect world, I also wish the KX2 were somewhat weather-proof or water-resistant. A couple of times, I’ve been operating in the field when rain caught me off guard. I feel like the KX2 is pretty vulnerable, so I either pack up the radio and stop operating, or I seek shelter if it’s available. It wouldn’t take a lot of moisture to penetrate the KX2 and there’s no way I’m letting rain ruin my rig. But I’m guessing weatherproofing would add significant cost.

So, did I experience any buyer’s remorse after purchasing the KX2?

Not in the least.  Between us, kind reader:  the KX2 has been a difficult rig with which to find fault. Price and inherent compromises for portability aside, there are really no serious negatives about this radio in my book. It suits my purposes very well.

Activating the Blue Ridge Parkway (PK01) with the Elecraft KX2 and "Silver Tip" 20 meter vertical. An effective combo!

Activating the Blue Ridge Parkway (PK01) with the Elecraft KX2 and “Silver Tip” 20 meter vertical. An effective combo!

Yet we reviewers cringe when our reviews appear this “glowing.”

I’m not a fanboy of any brand. I love to see companies introduce successful original products. I believe companies like Elecraft, CommRadio, LnR Precision, Elad, Icom, Yaesu, Kenwood, SDRplay, and the like are healthy for our hobby.

Competition and innovation are worthy friends.

Elecraft pushes our ham radio hobby forward, and it’s innovations like the KX2 that make our radio market and our hobby a dynamic and inventive space.

To be clear, I know the KX2 didn’t come out of nowhere. It’s the culmination of many iterations of Elecraft transceiver designs over the past eighteen years. Elecraft has taken feedback from customers, made notes, and improved their products with time, and it shows in this little rig.

The Elecraft KX2 is clearly a product of iterative agility.  It will, no doubt, be a market success.

I remember when Elecraft co-founder Wayne showed me the KX1 many, many years ago at the Dayton Hamvention. He told me that the KX1 was a step toward the perfect portable radio he’d dreamed of as a kid. The KX2 is simply that–and a profound upgrade of the KX1.  But more to the point, it might have been the portable of which I dreamed, too.

Check out the KX2 on Elecraft’s website: http://www.elecraft.com/KX2/kx2.htm

Free shipping for the C.Crane CC Skywave

fullscreen-capture-11302016-102121-pm

C.Crane has just sent an email with the promotion above: free shipping on the CC Skywave through December 6. As I’ve mentioned quite recently, I think the Skywave is an excellent little portable for travel. Certainly a nice gift for the shortwave listener!

Click here to view this promo on the C.Crane website.

Note that if you’re an Amazon.com shopper, the CC Skywave has free shipping every day.

A preliminary review of the PK Loop C-LOOP-HDSW6-18

eecraft-kx3-pk-loop

The Elecraft KX3 and the PK Loop C-LOOP-HDSW6-18

Over the past year, a number of SWLing Post readers have asked me to review the PK Loop portable magnetic loop antenna produced by Paul Karlstrand in Australia.

I finally caved in and purchased one.

I ordered the shortwave version of the loop, the  C-LOOP-HDSW6-18 in early November and received it about one week later.

sony-sw100-pk-loop

The Sony SW100 tuned to WBCQ.

I was first introduced to this antenna by SWLing Post contributor, Mark Fahey, who brought it to the SWL Fest and our 2015 PARI DXpedition.

Mark has taken his PK Loops (both the shortwave and mediumwave models) on his numerous travels around the world. He finds that they’re relatively effective portable antennas in RFI-dense environments like hotels and guest houses. They’re better at mitigating RFI than, say, portable wire antennas or telescopic whips.

Mark hooks up his portable SDR to the PK Loop and makes spectrum recordings (wideband recordings)–from, say, his hotel room in Kuala Lumpur–then takes the recording back home to listen and tune at his leisure via his laptop or tablet PC.  While I’ve certainly made spectrum recordings while travelling in the past, the appeal of such a portable loop antenna is what finally caused me to pull the trigger.

Overview

pk-loop

The PK Loop is a small loop antenna–measuring about 12″ in diameter. It’s encased in UV-stabilized PVC conduit and the matching box also seems to be made of PVC. It feels very durable and can, no doubt, even survive the wildest of luggage handling.

The PK Loop has an attached battery 9V battery holder, but can actually be powered by any 9-18 volt DC supply. Current consumption is less than 15 mA. On the matching box, you’ll find a tuning knob, a BNC connector, DC power in port and a HI/LOW gain switch. My loop shipped with a 2 meter BNC-BNC Cable, 3.5mm adapter, and DC Power lead to open ends.

Operation

Operating the loop is very simple:

  1. Power the antenna with a 9V battery or other DC source
  2. Chose either the high or low gain setting
  3. Place it on a stable surface (height from the ground is not a critical issue, but you should avoid placing it next to noisy electronics or mobile phones)
  4. Connect the PK Loop to your receiver’s antenna jack with the supplied cable
  5. Turn on your receiver to the desired meter band, then adjust the loop’s tuning knob until you hear the signal level peak
  6. Start listening, keeping in mind that as you tune around the band you may need to adjust the loop’s tuning knob for maximum gain

Loop antennas, in general, are fairly narrow-band and–unlike a Wellbrook or Pixel Loop–manual adjustments need to be made with the tuning knob to match the PK Loop as you scan across bands.

Still, I see why Mark favors the PK Loop for spectrum recordings: the bandwidth is wide enough that if I tune the loop to the middle of the 31 meter band, for example, it does a fine job covering the entire band.

On the air

pk-loop-kx2-sw100

My free time has been very limited since receiving the PK Loop earlier this month, but over Thanksgiving holiday, I took it to my family’s home that has relatively high RFI levels.

The following are a couple of videos I made with my Moto X smartphone. I’ll be the first to admit that these are not the best videos–I had no tripod and the Moto’s microphone leaves much to be desired–but I think you’ll still get the idea of how well the PK Loop works.

With the Sony SW100

Click here to watch on YouTube.

With the Elecraft KX2

Click here to watch on YouTube.

So far, I’m very pleased with the PK Loop. It does seem to mitigate noise better than other portable antennas I’ve used in the past and certainly improves my SW100’s reception. It makes SWLing with the Elecraft KX2 or KX3 easy and convenient.

One word of caution: if you use the PK Loop with a transceiver like the KX2, please turn off the ATU, and set the power level to 0W before using. The PK Loop is receive-only and will not handle any RF power.

Note that with the SW100, I have only used the PK Loop’s low gain setting. I’m a little nervous about overloading the SW100, so do not plan to use the high gain setting. The Elecraft KX2 seems happy to handle either gain setting: I imagine this will be the case with most general coverage transceivers and tabletop receivers.

More to come!

In a couple of weeks, I’ll be staying in a hotel room (likely with inoperable windows and heavy RFI) so I will attempt to put the loop through its paces and compare it with my radio’s built-in antenna.  Stay tuned!

UPDATE: Click here to read my follow-up review.

Post readers: have you used the PK Loop or other similar portable/travel antennas? Please comment!

Click here to view PK’s Loop antennas on Paul Karlstrand’s website.

Paul also sells his antennas and ships internationally on eBay–click here to view the selection.

pks-loops

Radios With Rotatable AM Antennas?

The Panasonic RF-2200 sports a rotatable AM/MW antenna

The Panasonic RF-2200 sports a rotatable AM/MW antenna

Many thanks to SWLing Post contributor, Mario Filippi (N2HUN), who writes:

With your broad knowledge of radios, wondering if you can add anything to this list of portable radios, past and present, that have 360 degree rotatable directional AM ferrite antennas. Reason is I am looking for an AM portable for the nightstand for nulling out unwanted AM stations while also doing a little DXing.

The list I have from data mining the ‘Net is:

New models with rotatable AM antennas:

  • CountyCom GP5/SSB,
  • Tecsun PL-360,
  • Grundig Satellite 750,

Older (vintage) models:

  • Panasonic RF-2200,
  • Panasonic RF-1150,
  • Panasonic RF-877,
  • Panasonic RF-1180
  • most RDF (Radio Direction Finder) radios that were used on boats

“Boom Box” variety:

  • Radio Shack 12- 795,
  • Emerson MBR-1,
  • Rhapsody RY-610.

[RDF radios] are kind of big, however Raytheon, Ray Jefferson, and Nova-Tech did have smaller model RDFs that could be considered table-tops).

The alternative is to build or buy a passive indoor antenna.

Maybe readers know of other models?

Thank you for your inquiry, Mario! I will do a little research of my own because you listed every model (and more) I could think of off the top of my head.

Post readers: Please comment with any models we could add to this list.

I will take all of the suggestions and make a master list to post here on the SWLing Post so it’ll be easier for others to research in the future. I’m pretty sure this question has come up before.