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Update: Sangean ATS-405 review

After publishing my initial review of the Sangean ATS-405 on July 25, I contacted Sangean and requested a sample radio for comparison purposes. Back story: there were some receiver performance issues that I suspected may have been tied to my particular ATS-405 unit. Sangean kindly dispatched another ATS-405 which I received last week. The following is an update to my initial ATS-405 review.

In truth, there were two main reasons I wanted another unit to compare to my initial review radio:

I wanted to see if the new unit showed improved performance–sensitivity, selectivity, and, specifically, noise floor–in comparison with the first review unit tested
I noted strong DSP “birdies” (noises) on 800 and 1600 kHz on the test model, while several of our readers commented that their ‘405s did not feature birdies

Shortwave sensitivity/selectivity and noise

I noted in my initial review that the initial ATS-405 had an ever-present noise, a sort of low-volume static hiss. The noise floor, while not high, certainly seemed to be higher than other comparable shortwave portables, and was most noticeable when tuned to marginal/weak stations. I suspect many listeners may not notice it unless they compare it with other portables.

Fortunately, my new review unit’s noise floor seems to be slightly lower than that of my initial review unit. [Perhaps this unit’s board is better soldered–?] The noise is still there, but can be better mitigated by judiciously using narrow filters and the three-position audio tone control.

I suspect this is a noise somewhere in the audio amplification chain, because I find it less noticeable with headphones, and more pronounced via the ATS-405’s internal speaker.

In terms of sensitivity and selectivity on the shortwave bands, I believe my new unit is identical to that of the initial review unit. That is to say, the ATS-405 is not an especially sensitive shortwave receiver, but fairly average, and thus will fit the bill for most but not for the discriminating weak-signal hunter. Frankly, even my $46 Tecsun PL-310ET does a better job of pulling in weak stations.

I’ve tried tinkering with the AGC settings and soft mute–very cool features!–in an attempt to improve sensitivity, but alas, these only help the quality and stability of the received signal.

Birdies

Immediately after opening the box of the new ATS-405 sample, I popped in a fresh set of AA batteries and tuned the Sangean to 1600 kHz AM. [If you read my initial review, I noted a strong DSP birdie on 1600 and (to a lesser degree) on 800 kHz].

At first listen, I was happy to note that the new unit lacks the wild DSP noise that overwhelmed my favorite local station on 1600 kHz.

As I listened more carefully, though, I did note a metronomic “chick” sound that was also present but partially buried in the noise on my initial ATS-405.

Below, I’ve embedded audio comparing the two receivers:

Initial review unit:

New review unit:

Listening to these samples, I realize I may have had the filter set to the middle position on the first sample and the wide setting on the second (hence, the brighter tone).

To further demonstrate the difference between the two, I made this short video; I start with my initial review unit, then switch to the new review unit provided by Sangean:

Note that this was recorded at least 100 feet from my house on the tailgate of my pickup truck. DSP birdies on 800 kHz sounded very much like the 1600 kHz sample, save the noise level on the latter is slightly lower and there are no broadcast stations in the background.

None of my other portables have digital noises or birdies on 800 and 1600 kHz.

So, the bad news: I do still hear a noticeable (and slightly annoying) internally-generated noise on the new review unit. The good news: it isn’t as objectionable as that on my initial review unit.

Summary

In short: I stand by my initial review of the Sangean ATS-405.

While the new ‘405 review sample seems to perform better than the initial ‘405 sample, I find the discrepancy somewhat marginal, especially since I spend the bulk of my time on the shortwave and mediumwave bands.

I’m not a fan of production runs where units vary so greatly from one to another, making accurate testing difficult. Therefore it’s quite possible you might receive a unit that performs better than those I tested…but unfortunately, the opposite is also true.

So, if you’re a Sangean fan, if you don’t mind the birdies on mediumwave, and if you mostly listen to strong shortwave stations, you may entertain purchasing an ATS-405. The keypad layout is almost identical to previous Sangean models.

To be clear, of course, this radio’s negatives above have been viewed under a microscope; the ATS-405 is not a “bad” receiver, it’s just not that exceptional. Other than the added mute/AGC/squelch features, when compared to its predecessors, it’s really not a better iteration.

In conclusion? For the $90 US price, I believe there are better receivers out there–such as the Tecsun PL-600 (which, as a bonus, has USB/LSB reception–and saves you $10, to boot).

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Initial review of the Sangean ATS-405

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Just last week, I received the new Sangean ATS-405 on loan from Universal Radio. Though I’ve only had the radio for a week, I thought I’d share a few un-boxing photos (by request) and my initial impressions/review of this radio.

Unboxing

The ATS-405 comes with a thick owner’s manual (in five languages), a 7.5 volt AC adapter, and a soft radio case. The package does not contain rechargeable batteries nor a clip-on wire antenna (like many Tecsun products do, for example).

Overall, the packaging accommodates the radio and accessories efficiently and would probably ship safely even if the carrier doesn’t handle it with particular care.

The first thing I noticed about the ATS-405 is the near-identical design and layout Sangean has used in their design of past shortwave radios. If you’re a Sangean fan, you’ll find all of the functions, buttons, and labels pretty much in the same place; virtually no learning curve.

Performance: first impressions

After unboxing the ATS-405, I installed a fresh set of AA batteries in it and turned on the radio…

Display

Like most Sangeans, the display is crisp, clear and can easily be read straight-on or at low angles, like when the radio is resting on its back stand, for example. If you look at the display from a higher angle, however, you’ll find that the LCD digits nearly disappear.

Back-lighting is perfect: it’s soft and consistent across the display, very much like the ATS-909X.

Audio

Audio from the internal speaker is good. It’s in the same league with most similarly-priced competitors.

Receiver performance

Keeping in mind that I’ve only logged a few days of listening time on the ATS-405, I do have some initial impressions about receiver performance across the bands:

Right side view (click to enlarge)

On a positive note, I believe FM performance is quite good. Perhaps not in the same league with my PL-660 or PL-680, but still the Sangean offers above-average sensitivity. I was able to pick up my distant benchmark FM stations with ease, though to help with the signal lock, I had to switch from stereo to mono reception.

AM/Mediumwave

AM reception is a bit of a mixed bag. I find that the ‘405’s overall sensitivity and selectivity are quite good for broadcast band listening.

When I first tuned around on the AM broadcast band, however, I found the noise floor a little too high. Regardless of whether I was tuned in to a station or not, there was an ever-present high-pitched hiss, like static. It was quite disappointing, especially since I read a review by Jay Allen that really complimented the AM performance on the ATS-405.

I trust Jay’s reviews, however, so I promptly contacted him. Jay pointed out that the problem may be that I was listening in the default “wide” filter setting on AM. And indeed, he was right–though I had changed filter settings a few times while tuned to local stations, I had moved it back to wide and didn’t make note of this. (The ATS-405, by the way, has three filter settings: wide, medium and narrow.)

Left side view (click to enlarge)

But the wide setting is really too wide, and was certainly the source for the bulk of the high-pitched hiss I heard. The best filter setting for most broadcast band listening is the middle position, which sounds like a 5-6 kHz filter. In the middle position, noise is decreased significantly. I also believe selecting the “music” audio tone setting helps dissipate some of the noise.

Regarding the noise floor: to be clear, I still feel like the noise level is slightly more noticeable, to my ear, on the ATS-405 than on the PL-660, PL-600, and PL-310ET when band-scanning or weak signal listening. This is most likely some internally-generated noise that somehow still meets Sangean’s engineering spec.

Local AM stations sound fantastic, and the ATS-405 can detect all of my benchmarks. AM audio fidelity is better than that of my PL-660 and, even, PL-310ET. When locked on a local station, the noise floor also seems to disappear. For some reason, I even find that the ATS-405 does a better job receiving local AM stations from indoors–even near noisy electronics–than other sub-$100 portables with which I’m familiar.

Uh-oh, birdies

The most disappointing discovery I made on the Sangean’s AM broadcast band is that it has DSP birdies. Birdies are internally-generated noises resulting from the outputs of the oscillators that form part of the DSP receiver circuit. While almost all receivers do have birdies somewhere in the receiver’s reception range, radio engineers try to keep them out of the way of the important parts of the band.

Unfortunately, my ATS-405 has strong DSP birdies on 800 and 1600 kHz. This is a big negative for me, since my favorite regional AM broadcast station is located on 1600 kHz (WTZQ). Rather than attempting to describe what the birdies sound like, here are a few audio clips that will give you an idea–I start with 1350 AM, which has no birdies and is representative of good AM reception:

WZGM 1350 kHz (broadcast sample with no birdie):

800 kHz (birdie on frequency with no broadcast signal):

WTZQ 1600 kHz (birdie on broadcast signal):

The ATS-405’s birdies almost sound like a jamming signal on 1600 kHz. Indeed, if this station were only located on a different frequency, I’m sure it would be quite audible on this radio…too bad.

Birdies on 800 and 1600 kHz may very well be deal-breakers for many of us. Again, since one of my favorite regional independent broadcasters is on 1600 kHz, it’s a deal-breaker for me.

Jay specifically mentioned a lack of birdies on the AM broadcast band in his review. It could very well be that he doesn’t hear them on his particular receiver–variations in quality control on a radio production line are certainly a real phenomena (the Grundig G3 is a case in point). This could indicate that some units may have pronounced birdies while others don’t. If you purchase an ATS-405, I would check to see if your unit has birdies after powering it up.

When I contacted an engineer for Sangean North America, and described my listening experience, he confirmed that he believed these are, indeed, DSP birdies. I may ask Sangean if they can send another ATS-405 for comparison.

On a more positive note, I checked harmonics in the HF/shortwave bands and heard no DSP birdies there.

Country of origin?

Bottom view with charge and keylock mechanical switches (click to enlarge)

One additional question I posed to Sangean: where is the ATS-405 made? One reader told me the radios are produced in both Taiwan and China. Thinking variations in quality control may be accounted for by two different production lines, I checked my radio to see where it was made. Unfortunately, my unit has no mention of country of origin; not on the radio, the box, the manual, behind the battery cover, nor on the back stand. It’s possible it could be marked internally, but I didn’t want to take apart a receiver I’ve been loaned.

Sangean came back with a firm answer:

“I can confirm that the ATS-405, along with all our radios, are manufactured in China. We have an office in Taipei for engineering, sales, marketing and customer support.”

Not a big surprise here; I expected China was the country of origin.

To sum up AM performance: if you aren’t bothered by the birdies on 800 and 1600 kHz, or if your unit isn’t producing them, you’ll find the ATS-405 a capable little AM broadcast band receiver.

Shortwave

Our HF propagation conditions since last Friday (when I first turned on the ATS-405) have been poor. Other than a few short band openings, I’ve struggled to hear anything other than the normal blow-torch broadcasters we hear in North America. Still, bad propagation conditions are actually good for reviewing some aspects of a shortwave receiver, so I used the opportunity.

In terms of sensitivity on the shortwave bands, I think the ATS-405 is mediocre. It lags behind my Tecsun PL-660, PL-600, PL-310ET, and CC Skywave. Adding a clip-on wire antenna to the telescoping whip (there is no aux antenna port) does help in terms of sensitivity.

Since I do most of my listening on the shortwave bands, this, too, is a deal-breaker for me. If you primarily listen to stronger shortwave stations, or spend most of your time on the FM/AM bands, then you might still consider the ATS-405.

The ATS-405’s selectivity seems to be on par with my other DSP-based portables. In truth, though, band conditions have been so unfavorable, I don’t feel like I’ve had ample opportunity to test selectivity. I’ll likely follow up this initial review with an update.

And as on medium wave, the noise floor on the shortwave bands seems a little high to me–especially with the filter set to the “wide” position.

Cool, innovative features

While I clearly haven’t been wowed by the ATS-405’s shortwave performance, I have been more favorably impressed with some of its innovative features: specifically, the ability to control squelch, tuning mute, and soft mute.

Sangean-ATS-405-Keypad Using the menu button (see image above), you can engage or disengage the tuning mute and soft mute by pressing the “2” or “3” buttons on the keypad, then using the tuning up/down buttons to toggle these features on and off. Squelch works the same way, using the “1” button and volume control to set the threshold.

This menu control works regardless whether the radio is turned on or off.

Of course, by using the menu button and the keypad, you can also control the ‘405’s tuning steps, AGC, clock, and backlighting functionality; each of these are marked in green next to the appropriate button on the keypad (see image above), a very useful feature.

I wish other radio manufacturers would give users the ability to control some of the DSP chip’s built-in functionality, as the ‘405 does with the muting–especially since over-active soft muting has been the downfall of several DSP-based radios. Thanks for trail-blazing, Sangean!

Summary

Invariably, all radios have strengths and weaknesses; here is a list of my notes from the moment I put the ATS-405 on the air:

Pros:

Improved features and controls:
- Soft Mute
- Tuning Mute
- Squelch
- AGC
Crisp, clear display
Good travel size, similar to the Grundig YB400
Good AM/mediumwave sensitivity
Three audio/tone settings: Music, Norm, and News
Good FM sensitivity
Dedicated mechanical switches for keylock, audio tone, FM stereo/mono, and charging.

Cons:

Lackluster shortwave sensitivity
DSP Birdies on 800 and 1600 kHz
Higher SW/AM noise floor (especially in wide filter setting)
No tuning wheel
No AUX antenna port
No shortwave SSB reception (AM only)
No audio line-out port

I’m going to hold onto the Sangean ATS-405 for a few more weeks, as I’d like to give it a more thorough test on the shortwave bands. I hope to follow up with a post offering a few representative recordings.

My nutshell opinion of the ATS-405 so far is that it’s a decent little radio with a lot of functionality and features for a rig in its price class. But overall, its performance seems to me rather mediocre. If you primarily listen to FM, you’ll be pleased. If you’re a mediumwave listener, you’ll be pleased only if you don’t mind the 800/1600 kHz DSP birdies. If you’re primarily a shortwave listener, you’ll need to carry a clip-on wire antenna to bring the sensitivity up to the level of similarly-priced receivers.

In short, I do want to like this radio unreservedly. But it appears that Sangean may need to pull up its socks on their quality control. Readers: please comment if you’ve purchased the ATS-405–I’m very curious to learn whether there are QC discrepancies in performance from one unit to the next.

PLEASE NOTE: After publishing this following review, Sangean kindly agreed to dispatch a second unit for comparison.

Click here to read my update to this ATS-405 review.

Follow the tag ATS-405 for updates.

Sangean ATS-405 Retailers:

Many thanks to Universal Radio for supplying this radio, on loan, for review!

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A review of the Kaito KA29 / Degen DE29

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While doing a somewhat random search on Amazon a few weeks ago, I stumbled upon a radio with a model number that I didn’t recognize–the Kaito KA29.

The form factor of the KA29 is very reminiscent of the Degen DE1129 I reviewed two years ago, but it’s smaller and sports a number pad on the front. On a whim, and with possible use of this radio in my charitable work at ETOW, I purchased one. At ETOW we have used similar radios with 16-32 GB Micro SD cards, chock-full of educational audio content. At $35, the KA29 is an affordable MP3 player and radio.

On a side note, I suppose I should mention that I was pretty disappointed with the DE1129 because I had hopes it would make for a great all-in-one portable radio recorder for ETOW. While the DE1129 could record FM/AM and SW radio directly, it had serious problems: it auto-adjusted the volume level during recording (one could not turn off the internal speaker), it degraded audio quality in recording, and medium wave was plagued with a “ticking” sound every 10 seconds. It produced digital hash on various meter bands. My summary of the DE1129: fine concept, poor engineering. Read my full review of the first version of the DE1129 here.

The Kaito KA29: First impressions

The Kaito KA29 is a cute little portable. Mine has a black body with orange band encircling the diameter. That orange band is actually a nice addition–it helps the radio show up a bit better and makes the ports a little easier to see when lighting is low.

The overall quality of the radio feels fine: the hard plastic body has a smooth matte quality and the buttons have a very tactile response. The telescopic whip antenna is long for the overall radio size, but is still a little on the short side for good HF gain. Oddly, unlike most radios, the antenna cannot swivel at its point of attachment to the chassis; it can only be extended and tipped side-to-side–but not front to back, or back to front. Like the DE1129, the KA29 lacks a back stand–a big negative in my book–but admittedly a back stand would be of little use while SWLing with this rig because the antenna can’t be swiveled or tipped into a useful vertical position. Hm. Also like the DE1129, the KA29 uses a slim rechargeable battery pack.

When I first turned on the KA29, I thought I had received a faulty unit: I pressed and held the power button for a second, the display lit up a bright green, I released the power button…and the unit turned off. After a little trouble-shooting, I realized that the KA29 requires holding the power button a full two seconds, until the “Kaito” brand name appears on the display.

Unfortunately, the KA29 antenna does not swivel.

This sluggish power-up response is truly an indicator of most functions on the KA29. It’s as if every function is controlled by a slow processor–which I’ve no doubt is the case.

As far as I can tell, all the menu functions are the same on the Degen DE1129; obviously, they’re built on the same firmware. Indeed, Kaito is the North American brand for the Chinese manufacturer, Degen; the Degen model number for this radio is DE29. In this sense, most functions are familiar to me.

Tuning

The one added feature of the KA29 that my version of the DE1129 didn’t have is a number pad, useful for direct entry of radio frequencies. I should note here that I (typically) toss the owner’s manual aside when I first get a radio, in order to test how intuitive its functions are. I spent quality time with the KA29 while traveling a few weeks ago, and as I didn’t bring the manual, I had to learn its functions via trial and error. It wasn’t until I returned that I learned how to use direct frequency entry; the is answer clearly stated in the manual: just key in the frequency, then press the appropriate band (AM/FM/SW) to go to that frequency. Pretty simple, actually. The response time for the radio to start playing the frequency you enter is only about one second.

Use of the tuning knob (located on the right side of the radio) is easy and straightforward–tuning up and down will move the needle 5 kHz steps between frequencies. Unfortunately, as on the DE1129, 5 kHz is the smallest tuning step available. The KA29 briefly mutes between frequency changes, so when tuning slowly it’s very noticeable. If you tune quickly, the KA29 will produce snippets of audio as you pass signals, but I find it often skips over even very strong signals. In short? Though I suppose it could be worse, I do not like tuning the KA29.

I should also mention that the KA29 has no adjustable bandwidth; I’m guessing the AM bandwidth is stuck at around 6 or 7 kHz.

Performance

While I no longer have the DE1129 in hand for side-by-side comparison, my impression is that performance between the two radios is very similar.

Audio fidelity

Herein lies the strength of the KA29. It obviously uses the same speaker technology (with an acoustic chamber) that the DE1129 uses. You will be favorably impressed with the audio from this wee radio–it is quite robust for a pocket radio of this size, and in a small room, almost room-filling. It sounds fantastic on FM and AM alike–you can even hear a hint of bass. One day, I tuned the KA29 to a local AM station and listened quite comfortably in another room. Impressive.

But what about receiver performance?

FM performance is quite good. I’ve used the KA29 in two different cities, and found that it could detect most of the same FM stations my other portables picked up.

AM/Medium Wave

I was pleasantly surprised to note the absence of the annoying ticking sound I heard in the DE1129; it appears Degen engineers have succeeded in eliminating this distraction. In general, I believe the KA29 performs acceptably on medium wave for basic local and nighttime clear channel broadcast listening. The AGC circuit is not ideal, though, for any sort of medium wave DXing; don’t consider the KA29 for MW DX.

Shortwave

If the KA29 is better than the DE1129 on the shortwave bands, the improvement is negligible. You’ll be fairly happy with the KA29 while listening to strong shortwave broadcasts. During my review, I listened to the new Global 24 a few hours on 9,395 kHz–an easy catch on the east coast of North America–and the KA29 was fairly stable, producing rich audio.

Here are the cons on shortwave:

Automatic Gain Control

While listening to weak stations, you’ll discover the KA29 to be somewhat sensitive, but again, the AGC circuit is just too active to listen comfortably for very long.

Noise floor

The noise floor is more obvious while listening to weak signals: I believe much of the noise is coming from the internal electronics of the KA29. It produces an audible digital hash sound that makes weak-signal listening a bit of a chore.

Images

Quite often as I tuned around the shortwave bands, I noticed that FM stations bleed through the audio. Check out this audio sample as I attempted to listen to Radio Ryhad:

Indeed, even if the shortwave station has a relatively strong signal (like this recording of Global 24) you can often hear noise:

For comparison, listen to the other radios I recorded at the same time for the ultra portable shoot-out.

Onboard Recording

Fortunately, several of the recording problems I noted with the DE1129 are no longer an issue with the KA29.

Fixed volume

The DE1129, when recording radio, had the exceedingly annoying habit of automatically setting the internal speaker’s volume to a high level. While recording, this could not be changed.

Fortunately, this problem has mostly been addressed in the KA29, which does not increase the volume while making a recording, but still fixes the volume at the level set at the recording’s start. I didn’t find this to be much of a problem.

Audio quality

The recording performance is better than that of the DE1129, which produced noisy, muffled recordings. The KA29 will produce fair audio recordings on AM, on FM, and on shortwave. One drawback: you will note a low-volume, high-pitched static noise–a hiss, to be specific–inherent in every radio recording, regardless of band. While it’s not too offensive, nor enough to deter me from making direct radio recordings (at least of strong stations), there is still much room for improvement. Obviously, I can use the headphone jack and an external digital recorder to make better radio recordings. But the convenience of an all-in-one recording device plus radio outweighs the slight hiss in the internal recordings it produces.

All in all? I’m reasonably pleased with the radio recording capabilities of the KA29, and the improvements it’s made over its predecessor. If the Degen engineers could lower the KA29’s noise floor and fix the imaging problems, and add 1 kHz tuning increments, this could be a good value all-in-one radio, a real contender.

Summary

Ever radio has its pros and cons. The following is a list I made while reviewing the KA29:

Pros:

Keypad entry
Great audio for a tiny radio
FM reception quite good
MP3 playback audio is good
Onboard radio recording acceptable (see con)
9/10 kHz select-able medium wave steps

Cons:

Sluggish response to most actions; if (for example) volume control has been used, you must wait nearly 4 seconds before using another function
Awkward menu to navigate
No bandwidth selections
Imaging on SW bands
Fixed 5 kHz steps on shortwave
No adjustable bandwidth
Digital noise on portions of MW and SW bands
Low audio hiss present in all internal radio recordings (see pro)
No back stand
Antenna does not swivel 360 degrees for optimal placement

Conclusion?

If you’re looking for a pocket radio to make local radio recordings on-the-go, and the quality of your recordings is not a major concern, you might give the KA29 a try; chances are you’ll be fairly pleased with the affordable KA29.

If you’re a shortwave radio hobbyist or DXer of any stripe, however, don’t waste your time or money on the DE1129. Instead, pitch in $10 more and buy a Tecsun PL-310ET–it has no MP3 recording or playback, but it will receive circles around the KA29.

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The best general coverage transceivers for shortwave listening

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This article originally appeared in the May 2014 issue of The Spectrum Monitor Magazine.

The Icom IC-7200 has an excellent general coverage receiver

Like many amateur radio operators, I became interested in HF radio because of my real passion for shortwave radio listening. During my first fifteen years as an SWL, I relied on portable receivers, in my case, the Zenith Transoceanic, Realistic DX-440, and Grundig YB 400. The Zenith was my home radio; I traveled with the DX-440 and YB400. I felt like I had the world at my fingertips.

In the mid 1990s, as an undergraduate, I decided that I would pursue my ham radio license–while on my student budget, I dreamed about upgrading to a proper tabletop receiver like a Kenwood, Icom, JRC or Drake. But when I found out the real cost of buying an HF transceiver (gasp!) I realized that all of my resources would go into a transceiver, and the receiver would just have to wait.

The Icom IC-735 general coverage transceiver

Then, as I was studying for my license in 1997, ham buddy Eric McFadden (WD8RIF) invited me over to his house to test drive his Icom IC-735 transceiver. Eric, along with another friend/elmer, Mike (K8RAT) encouraged me to look for a used IC-735 for an affordable first HF radio.

I recall very well tuning around the ham bands at Eric’s QTH and being most impressed with how the IC-735 seemed to pull signals out of the static. It was my first time ever tuning a tabletop rig, and I was instantly hooked. Later, I asked Eric if the ’735 could also tune in shortwave radio broadcasters? His energetic response: “Sure! The ‘735 is general coverage,” then demonstrated by tuning to the 31M band.

Needless to say, I was absolutely amazed by the number of stations one could hear on this ham radio transceiver. Of course, its sensitivity surpassed anything I had ever owned, especially considering that the rig was hooked up to a proper outdoor wire antenna. I realized then that a ham radio transceiver and receiver–in the same radio–were within my financial grasp.

So, what is “general coverage”––?

A ham transceiver with “general coverage” means that the receiver portion of the radio is not limited to the ham bands only; these receivers typically receive between 100 kHz and 30 MHz (i.e., the full medium and shortwave radio spectrum). Many transceivers, starting in the 1980s, employed a general coverage design as a feature of the radio. Some radios implemented general coverage receiving better than others. In most cases, there was a compromise to performance when the receiver was opened to general coverage reception, so many manufactures held to a ham-band-only platform to optimize performance where hams sought it most. Today, receiver architecture can better accommodate general coverage without compromising sensitivity and selectivity on the ham bands.

Still, in 1997, my Icom IC-735 met all of my ham radio and SWLing expectations. For years, in fact, it was my main SWLing rig. Was the IC-735 as good as a proper tabletop receiver? No. The truth is that its filters and performance were most favorable for the ham radio bands. But as I mentioned, this compromise is much less profound in current transceiver design, and general coverage is status quo.

Benefits of general coverage

Apps like Amateur Radio Exam Prep make exam practice easy and convenient

While the benefit of having a transceiver that can tune the full broadcast band may seem obvious, there are two reasons I always have at least one general coverage transceiver in my radio arsenal:

Since I like to travel and save space, a small general coverage transceiver (e.g., the Elecraft KX3) kills two birds with one (portable) stone;
If an emergency, such as a dire weather event were to occur, general coverage will allow me the ability to monitor international broadcasters and local AM (mediumwave) stations while still performing any emcomm (emergency communications) duties.

Another advantage to owning a proper HF transceiver is that, if you currently do not hold an amateur radio license, this may just be the push you need to get your ticket! All you’ll need to do is take two multiple choice tests (Technician and General) to unlock the full potential of your HF transceiver, and you’ll soon enjoy hamming it up with the rest of us.

Cons of general coverage

As I mentioned, general coverage transceivers can present something of a compromise in performance; after all, the rig’s main duty is to perform on the ham bands. Here are a few compromises to be aware of:

With a few exceptions, purchasing a ham transceiver is pricier than purchasing a comparable dedicated broadcast receiver
AM filters are often much narrower than broadcast receiver filters
In many radios, you may be faced with a choice of optimizing filter selections for ham radio use (SSB or CW) or broadcast use (wide AM filters, etc.)
Older general coverage transceivers (circa 1980s and 90s) may have somewhat compromised ham band receive performance
Some general coverage transceivers may actually lack AM mode. All broadcast reception will basically be tuned via SSB (or better known as ECSS)
General coverage transceivers typically lack synchronous detection

Another consideration: while anyone can purchase a general coverage ham radio transceiver, until you hold an amateur radio license with HF privileges, you cannot legally transmit using your radio. I doubt that any readers would consider doing this intentionally, but again your radio is designed to transmit, so this could be done accidently especially if you’re not familiar with transceiver functions. Transmitting unintentionally can have more than legal repercussions: 1) if you transmit with a mis-match between your transmitter and antenna, you could harm the finals in your transceiver; 2) you could damage your radio and/or antenna if using a receive-only antenna (like a mag loop); and 3) you could even receive RF burn. To avoid this, and make it foolproof, search the web for modifications to temporarily disable “transmit” on your radio if indeed you never intend to transmit.

A note about power supplies

My trusty Astron Power Supply

Unlike stand-alone receivers, most general coverage transceivers require an external DC power supply. If you do not have a power supply, you will need to fit this into your budget. Power supplies can be costly, but also an investment in longevity. With a little knowledge up front, you can be selective and save on your power supply purchase. As I have been using the same power supply (an Astron RS-35A) since 1997, I turned to my friend Fred Osterman, president and owner of Universal Radio, for suggestions on power supplies currently in production.

Fred pointed out that if your only goal is to power a transceiver for the receive function, there is no need to invest in an expensive power supply. He suggests a reliable, regulated power supply, such as their popular $35 (US) Pyramid PS-4KX: at 3.5 amps; indeed, the PS-4KX will be more than enough power for any transceiver in receive mode.

Of course, if you plan to transmit at full power–and unless you have a QRP radio–you will need a power supply that can handle the load. For this purpose, Fred suggests two excellent options:

the affordable, portable and lightweight QJE PS23SWI 23 amp switching power supply ($79.95 US), or
the Astron RS-35A 25 amp linear power supply ($179.95 US)

Again, I’ve had my trusty Astron RS-35A since 1997, so once you’ve invested in a good power supply, you should be all set for many years–and radios–to come.

My old 1 amp regulated laptop power supply is more than adequate for SWLing on the Elecraft KX3

Transceivers: Good bets for $1,600 US or less

There are dozens of general coverage transceivers currently on the amateur radio market. Indeed, I don’t believe there are any rigs now in production that do not have a general coverage receiver, or at least the option to add it. Prices vary greatly, but I will assume that most SWLs that are considering the leap into amateur radio will want a radio that costs less than the price of a tabletop radio/transceiver combo. Just to keep things simple, we’ll limit our list to $1,600 US or less, beginning with the least expensive option.

Alinco DX-SR8T ($510 US)

The Alinco DX-SR8 has a detachable face plate

The DX-SR8T ($510 US) is one of the most affordable general coverage transceivers on the market. To be clear, the DX-SR8T lacks many of the frills and features of pricier rigs, but it’s a surprisingly good transceiver and, of course, general coverage shortwave receiver. Indeed, Alinco actually markets a receive-only version of this radio (the DX-R8T, $450US); it is identical in every respect to the DX-SR8T, but simply has no transmit function.

While I have only used the DX-SR8T on a few occasions, I have spent a couple of years with the DX-R8T, and even reviewed it extensively in the SWLing Post. My DX-R8T began life as a review unit that I purchased––it was an early production unit, and even retained the transmit LED indicator found on its sibling, the DX-SR8T. Consider paying the extra $60 US for the DX-SR8T, and you’ll have a basic, full-featured transceiver.

You can purchase the IC-7200 from Universal Radio or other ham radio equipment retailers.

The Icom IC-7200 ($900 US)

The Icom IC-7200

The IC-7200 delivers a lot of performance for a sub-$1,000 price. Its general coverage receiver will rival that of the venerable R75, and its AM filter can be widened to 6 kHz. Ergonomics are better than average. Plus, it has Icom’s twin passband tuning: the IC-7200’s general coverage receiver actually tunes from 30 kHz all the way to 60 MHz. The IC-7200 is a fantastic value.

You can purchase the IC-7200 from Universal Radio or other ham radio equipment retailers.

The Elecraft KX3 ($900 kit; $1,000 factory pre-assembled)

The Elecraft KX3

The Elecraft KX3 is my general coverage transceiver of choice. There’s so much about this radio that I like: it’s nearly as compact as my portable shortwave radios, it’s a full-featured transceiver, it can operate on batteries, it has good ergonomics, and is made and supported by Elecraft, right here in the USA.

Its sensitivity and selectivity rival radios three times its price. The only negative I can point out about the KX3, in comparison with many other general coverage transceivers, is that its AM filter is limited to a width of 4.2 kHZ. When I first learned of this, I thought it would be a deal-killer for me. But I was wrong. The audio sounds much more robust and “wide” than I would ever have guessed. It’s excellent. Want more details? I made an extensive review of the Elecraft KX3 in the SWLing Post.

You can purchase the Elecraft KX3 directly from Elecraft.

Note: Elecraft tech support can instruct you in disabling “transmit” on the KX3, if you wish.

Update: Also check out the KX3’s new sibling, the Elecraft KX2.

The Kenwood TS-590S ($1,500 US)

The Kenwood 590S

The TS-590S has an excellent general coverage receiver and brilliant audio fidelity. With one of the lowest noise floors in the business, the 590S is well respected amongst amateur radio operators and shortwave radio listeners. If you doubt this, see how the TS-590S compares on Rob Sherwood’s receiver test data page.

You can purchase the Kenwood TS-590S from Universal Radio or other ham radio equipment retailers.

Updates

[June 13, 2020] Since originally publishing this article, a number of general coverage transceivers have hit the market. Many of them are very affordable. Here’s a short list of additions:

Elecraft KX2 (click here to read our full review)
Xiegu G90 (click here to read more)
Yaesu FT-891 (click here to check it out at Universal Radio)

Looking to spend a little more?

The Icom IC-7600

If you happen to be a ham looking to upgrade their transceiver for benchmark performance, you may be willing to dedicate more funds to your purchase. My buddy, Dave Zantow (N9EWO), a discriminating reviewer for the late great Passport To World Band Radio, is very pleased using his Icom IC-7600 for broadcast listening. He told me recently, “[The IC-7600 is] not perfect, of course, but does perform near excellent and also has a great display [with] a very useful spectrum scope.” Dave has a full review of the IC-7600 posted on his website.

The Ten-Tec OMNI VII

I have also been impressed with the superb broadcast reception of the Ten-Tec OMNI VII ($2,800 US), Ten-Tec Eagle ($1,800 plus wide AM filter) and Orion series transceivers. While the OMNI VII and Orion II will set you back more than $2,000, used original Orions can be found for $1,800 and even less. Ten-Tec still services all of their radios at their headquarters in Sevierville, Tennessee.

Used transceivers

If you would like to save some money, consider searching the used market for one of the radios mentioned above. Alternatively, look for some of these select transceivers that are no longer in production, but are known to have capable general coverage receivers (do note that what follows is simply a selection, not a comprehensive list):

Icom IC-706MKII, IC-746 Pro, IC-703 (QRP version of the 706MKII), IC-7000, IC-735, and IC-745
Kenwood TS-570, TS-870, TS-930, and TS-940
Yaesu FT-840 (with optional AM filter), and FT-1000 series (very venerated series and still pricey even used)
Ten-Tec Orion and Orion II, OMNI VII, Eagle and Jupiter

Keep in mind, when you purchase a quality used radio, you can get excellent value for the performance it will reward you. The flip side of this, though, is that if you purchase a radio that hasn’t been in production for over a decade, the chances of finding replacement parts become more difficult with each passing year.

For more hints on purchasing a used rig, check out our Marketplace page.

With the option wide AM filter installed, the Ten-Tec Eagle makes from an amazing broadcast receiver. They are available new from Ten-Tec, but can also be found used.

Summary

If you plan on investing in a fine communications radio, it may be best to economize by investing in a good general coverage transceiver. For the prospective ham, the leap from a tabletop receiver to a fine general coverage transceiver may be less than $300. To prove my point, if an SWL planning to get a ham ticket asks about buying the venerable Icom R75, I would encourage spending $250 to get the Icom IC-7200, instead.

Indeed, with modern receiver architecture, there is little reason not to invest in a good general coverage receiver that you can also use to communicate all over the world when you get your ham ticket. And, need I add, it’s fantastic fun for the money.

If you would like to learn how to become a ham radio operator, check out this great introduction at the ARRL website.

Do you have a radio suggestion that I did not mention? Please comment!

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Results of the Shortwave Portable weak signal shoot-out

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Thanks to all who participated in our shoot-out! Last week, I posted three recordings of a weak shortwave broadcast in an attempt to evaluate which recording–thus which radio–our listeners prefer. The test was “blind” in that, though four radios were evaluated, only three recordings were posted, merely labeled, “Sample #1,” “Sample #2,” and “Sample #3,” respectively.

The radios tested were not just average radios. Rather, they represent the best of the truly portable radios currently on the market, namely: the Sangean ATS-909X, the Tecsun PL-880, the Tecsun-PL660 and the Sony ICF-SW7600GR.

Indeed, the most popular question I receive from SWLing Post readers is about two or more of these models, asking,”which is best?”

The samples

To refresh your memory, I’ve embedded the audio samples below–but if you haven’t yet, I would encourage you to read our previous post (and the great reader comments following!) before proceeding.

The recordings in our samples are of Radio Romania International on 11,975 kHz. Normally, the signal would have been stronger, but propagation was rough, and QSB (fading) was pronounced at times. Note that I recorded all of these samples with my Zoom H2N digital recorder via a line-in connection, using the radio’s headphone jack. Since not all of the radios have a line-out jack, I used the headphone jack each time and simply set the volume and line-in gain to the same level.

Sample 1:

Sample 2:

Sample 3:

And now, here is the sample I intentionally left out in my previous post…Sample #4. I didn’t include it in the evaluation because, frankly, it was such a weak performer compared with the other three; I knew it would take last place:

Sample 4:

With that in mind, we’ll start with the radio behind Sample 4:

Sangean ATS-909X ($200-250 US)

Many readers guessed rightly that the Sangean ATS-909X was the radio omitted. Evidently, it is known for its lack of sensitivity when only employing its telescoping whip antenna. You’ll notice that, most of the time, the RRI broadcast is lost in the static.

Frankly, I was somewhat surprised that the ATS-909X didn’t perform better. It has a loyal following amongst SWLing Post readers and has been a popular radio on the market for the past three years or so. While I’ve used the ATS-909X in the past, I have never owned one, and had never done a side-by-side comparison.

To perform this test, I borrowed the 909X from a friend who usually has it hooked up to an external antenna. In fact, this is when I learned that the 909X performs admirably when hooked up to an external antenna.

In my tests, however, I didn’t want to hook up external antennas. I believe that for a radio to be evaluated as a portable, it must be judged on its ability to receive signals from its telescopic whip antenna as a base line.

But let’s move on to the radios you did hear in our weak signal evaluation…

Let’s take a look at the radio behind Sample #3, the radio our readers voted to take last place in terms of weak-signal listening:

Tecsun PL-880: Sample 3 ($150-160 US)

With the exception of three votes (out of more than seventy), Sample #3–the Tecsun PL-880–was overwhelmingly voted worst in this weak-signal shoot-out.

The bulk of your criticisms focused on the fact that the PL-880 did not handle fading as well as the other radios. When the signal was at a peak, it sounded great, but in QSB troughs, the signal became unintelligible and you could hear DSP artifacts and distortion.

But is the PL-880 a “bad” radio? Absolutely not. Indeed, I gave it pretty high marks when I reviewed it last year. It’s just not the best choice for weak-signal listening–at least in its current firmware version. Note to Tecsun: I do believe it may be possible to tweak this portable’s AGC circuit so that it handles fading better…

But let’s move on to the other contestants. Here’s our second-place portable:

Tecsun PL-660: Sample 2 ($110-130 US)

During the first day of voting, the Tecsun PL-660 actually had a noticeable lead on the other radios. I’m not surprised. The sensitivity was better than the rest of the contestants, in my opinion. The received audio was clear and seemed to pop out of the static better than the others.

Overwhelmingly, those who didn’t vote the PL-660 as best, voted it as second. Their main criticism was that the PL-660’s AGC was a little too active and less stable than the radio which actually took first place.

And with no further ado, here’s our winner:

Sony ICF-SW7600GR: Sample 1 ($130-150 US)

Surprised? I was!

After I evaluated the blind test myself, I was certain the PL-660 would be the winner with its stronger sensitivity. But the result–and reader comments–proved me wrong. More of you placed a value on the Sony’s rock-solid AGC circuit which handles the peaks and troughs of fading better than the other contenders.

Commenters noted that the Sony’s audio and stability lent itself to easier, less fatiguing, listening. Keep in mind, though, that many of these same commenters mentioned that the PL-660 (Sample #2) would be their preference for identifying a station in under weak signal conditions.

Now let’s look at the raw data, and then discuss what it all means.

The data

The Sony ICF-SW7600GR was voted:

first place 41 times,
second place 2o times, and
third place once

The Tecsun PL-660 was voted:

first place 23 times,
second place 33 times, and
third place twice

The Tecsun PL-880 was voted:

first place never,
second place three times, and
third place 53 times

I’ve attempted to place this data into a bar graph to make it a little easier to visualize: If you noticed that these numbers don’t completely add up, it’s because responses were inconsistent.

Most survey participants listed their preferences in order (i.e., first, second, and third place). Some respondents only listed their favorite of the three, while others only listed the one they didn’t like. No one responded with a tie between the radios, all had an opinion.

Another way of reading the results

SWLing Post reader “Radio Flynn” helped me with some additional data interpretation this morning. He put together this analysis (download as a PDF), and commented:

“[A]lthough a majority of people choose sample #1, nearly everyone ranked either sample #1 or sample #2 as preferred, and the average ranks are very close, closer than the raw percentages would indicate. I have not done a statistical analysis so I don’t know if the difference in mean rank between #1 and #2 is significant (in other words, I don’t know if there is a significant preference for #1), but you can say that either sample 1 or sample 2 would be acceptable to almost everyone, and sample 3 clearly last choice.”

Radio Flynn also pointed out that next time I do this sort of test (and I will be doing another!) that I should keep votes consistent by asking everyone to rank their preference. Excellent suggestion; I’ll be sure to do so.

So the Sony ICF-SW7600GR is the best radio…right?

Not exactly.

Herein lies the difficulty of suggesting the “best” radio for any particular listener.

This test only evaluated weak signal sensitivity under rather rough conditions. The Sony was “the winner” in this respect.

But this doesn’t tell the whole story.

I’ve had my Sony ‘7600GR longer than any of the other portables in this contest and it is invariably the radio I reach for when I want to make a field recording. I prefer the Sony because it has good sensitivity, a stable AGC, excellent single-sideband selectable sync detection and it can handle being connected to a long external antenna. Indeed, it was the Sony I packed when I spent the summer of 2012 in an off-grid cabin in the Canadian maritimes. In short: my Sony ICF-SW7600GR is my “old faithful.”

But frankly, when I travel, I reach for the PL-660 more often than not. Why? Yes, the Sony has great receiver characteristics, but its ergonomics leave a lot to be desired. I use my Sony when I plan to key in a frequency and leave it there. The PL-660 is a joy to operate, has simple direct-frequency entry, an excellent auto-tune feature, not to mention, a stable sync detector.

If I want to identify a signal buried in the static, I reach for the PL-660.

If I want to do casual listening and am less concerned with DXing, I reach for the PL-880. It’s a solid radio and has a quality feel to it (running neck-and-neck with the ATS-909X in this respect). Of this bunch, it has by far, the best audio from its internal speaker. If I want armchair listening, I reach for the PL-880. It’s also an excellent SSB receiver–one of the best in this group–and offers more filter selections.

In summary, it’s not always easy to suggest which radio is best…I must ask in response, “Best for what?” The data from this test proves this, as our readers who ranked their favorites backed up their choices with consistent and valid comments.

What do you think?

Before long, I plan to pit these radios (and perhaps another?) against each other in terms of their synchronous detectors in another blind test. It may take a while to work this up. Your enthusiastic responses, however, completely justify it.

Stay tuned!

Resources:

Sony ICF-SW7600GR
- On the SW Radio Index
- Retailers:
Tecsun PL-660
- On the SW Radio Index
- Retailers:
Tecsun PL-880
- On the SW Radio Index
- Retailers:
Sangean ATS-909X
- On the SW Radio Index
- Retailers:

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Review of the Elecraft KX3: world-class transceiver, superb shortwave receiver

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I originally wrote this review for Monitoring Times Magazine, May 2013 issue (pages 56-57). The review that follows has been expanded and includes updates.

The Elecraft KX3 Transceiver (Click to enlarge)

You may have noticed that in the past few years, while more and more software defined radios (SDRs) are appearing on the market, fewer and fewer traditional tabletop shortwave receivers are being introduced. Most of the receivers in production, meanwhile, are quite mature, having been in production for years. For those of us who still have an appreciation for the traditional front panel, tuning knob, and portability of an all-in-one tabletop receiver, perhaps we should look to the active ham radio transceiver market.

Introducing the Elecraft KX3

Besides being an avid SWLer (ShortWave Listener, for the newbies out there), I’m also a ham radio operator (callsign: K4SWL). But if you’re not a ham, you may not be familiar with the innovative, US-based radio designer and manufacturer, Elecraft. First of all, note that “US-based” adjective: this is an increasingly rare phenomenon in the world of radio production, and it deserves a word of praise up front. Elecraft started life as a kit manufacturer, focusing on QRP ham-band-only radio transceivers that were effective, affordable, and maintained a very high level of performance. Their K1, KX1 and K2 transceivers are legendary, and I’ve had the good fortune to own them all at some point along the way. Their K3, introduced in 2008, became a benchmark transceiver and still tops the charts in performance; it’s truly a choice DXpeditioner’s radio.

In 2011, Elecraft introduced the KX3–a portable SDR transceiver with a full-featured knob-and-button user interface that doesn’t require connection to a computer to operate. At the Dayton Hamvention, the KX3 instantly drew crowds, as it was unlike any other transceiver on the market. I was there, and like others in the crowds around the Elecraft booth, I was eager to try out this full-featured transceiver, especially upon learning that even the basic, no-options model has a general coverage receiver. A ham transceiver with “general coverage,” incidentally, means that its receiver is not limited to the ham bands only; these receivers typically receive between 100 kHz and 30 MHz (i.e., the full shortwave radio spectrum). That morning at the Hamvention, I quickly made my way to one of Elecraft’s owners, Wayne Burdick, to ask him,“Would the KX3 make for a good shortwave radio receiver?” Wayne’s prompt response: “Yes.”

That was enough for me: more than ever, I simply couldn’t wait to get within reach of a KX3. Why? I love to travel and take radio along, but I’ve always had to haul separate transceivers and receivers for my separate-but-related hobbies: 1) ham radio and 2) SWLing. Perhaps the KX3 would suit both purposes? I was hopeful. If this was true, with a KX3, I could have a full-featured QRP transceiver and a shortwave receiver in one…and a portable one at that. Ideal!

I just had to get my hands on one to find out.

(Click to enlarge)

A closer look

Though the KX3 was introduced in the summer of 2011, it didn’t start shipping until a few months later, and there was a backlog of orders for it. Fortunately, my good buddy, Dave Anderson (K4SV), was among the first purchasers of the KX3, and he was generous enough (and trusted me enough!) to let me borrow it.

At first glance, the KX3 resembles just the faceplate of a tabletop radio: it has a large tuning knob, wide, clear amber backlit display, and a traditional set of function buttons and multi-function knobs…but not much else. Or so it appears, as there’s no bulky chassis. Connections for microphones, DC power, headphones, IQ out, key and PC interface are located on the left side panel of the radio, while the RF connection (a female BNC) is on the right side panel. The KX3 has built-in folding feet, quite sturdy, that allow the radio to be tilted at a comfortable angle for tabletop operation.

To best evaluate the KX3, I’ll first discuss some of the features that would interest a ham radio operator, then focus on those best suited to the SWLer.

There is a hidden keypad for direct frequency entry (notice the numbers printed next to the multi-function knobs and buttons?)

Everything for the Ham

If you’re a ham, you’ll love the feature set on the KX3. It must be one of the most comprehensive set on any radio I’ve ever used. At a bare-bones level, meaning without adding any options, the basic KX3 is truly an all-in-one QRP transceiver.

Of course, it will function on any mode: USB, LSB, CW, data, AM and FM. The output power is adjustable from 0 to 10 Watts. You can easily adjust the DSP filters, AF, RF, passband, and notch all from dedicated buttons and knobs. It even has a memory keyers for both CW and voice.

You say you prefer digital modes? Not only will the KX3 natively decode RTTY and PSK31 and display the scrolling text on the display, but you can also send RTTY and PSK31 without a PC. How? Simply set the appropriate data mode and use your key to tap out your message in CW. Though you will hear the CW side tone, the KX3 will transform your code into RTTY or PSK-31, and send. Hypothetically, armed with only a KX3, you could run a RTTY contest from the field with no computer. Remarkable.

The variable DSP filtering is most impressive and the KX3’s ability to block adjacent signals is benchmarked. Indeed, if you look at Sherwood Engineering’s receiver test data rankings (http://www.sherweng.com/table.html), which are sorted by third-order dynamic range (narrow spacing), the KX3 is second only to the Hilberling PT-8000A, an $18,000 transceiver.

With the installation of the $170 optional internal automatic antenna tuner (the KXAT3), you will be able to tune most any wire antenna on the go, with no need to carry an external ATU.

In short, for the ham, the KX3 offers a cornucopia of features, too numerous to list here; but I can at least tell you that I discover something new on this radio almost every day and continue to be amazed by the features on this transceiver, especially considering that it costs only $1000 ($900 in no-solder modular kit form).

The Elecraft KX3 is built for travel and portability–here we compare its size with the Grundig G3

For the SWLer

We’ve talked about the KX3 as a ham radio transceiver, but how does it stack up if your primary interest is to just sit back and listen to broadcasts? Short answer: Very, very well.

The KX3 is loaded with features that would please even the most discriminating DXer.

First, on the faceplate, the KX3 has a multi-function knob that controls both the AF and RF gains. It’s very simple to use, even though I’m not a fan of switching between the AF/RF gain controls on the same knob. AF gain is what most of us refer to as a volume control and many dedicated shortwave receivers lack an RF gain control even though it’s a vital tool for broadcast listening in noisy conditions. By default, the KX3 RF gain is set to zero; turning the RF pot counter-clockwise will decrease RF gain.

Grundig G3 (left), Elecraft KX3 (right)

The KX3 also has three different preamp settings, which are useful for amplifying weak stations, as well as an attenuator for local or strong broadcasters. The KX3 has passband and notch filtering, and an auto-notch function that effectively deals with heterodynes from nearby carriers. The KX3 also has DSP noise-reduction (NR) for noisy band conditions (or to help a signal “pop” out from the noise) and noise blanking (NB) for local RFI.

Many automatic gain control (AGC) parameters are adjustable, too, so they can be tweaked for AM fading and weak-signal DXing. The fact is, the KX3 has more built-in receiver controls than the dedicated tabletop shortwave receivers I’ve owned.

Audio

Left side panel of the Elecraft KX3 (click to enlarge)

To be clear, however, there is one negative in the architecture of the KX3 when viewed through the eyes of an SWLer. The KX3 is designed around the amateur radio operator and AM bandwidth is narrower than you will find on most dedicated tabletop shortwave receivers–indeed, a commonality on any general coverage ham transceiver. The KX3’s AM bandwidth can only be widened to 4.2 kHz–a figure that almost made me dismiss this radio’s SWLing abilities out of hand. I’m glad I didn’t let that spec stop me, though: I had read many a favorable comment from KX3 owners who used the radio to listen to the broadcast bands. Their comments on the audio were very positive, and for good reason.

What the KX3 lacks in wide bandwidth is made up for by the 32-bit floating point DSP architecture. I’m not sure how, but the KX3’s audio fidelity “sounds” much wider than 4.2 kHz. Indeed, I still have a difficult time believing that the filter is not closer to 7-8 kHz in width. When using headphones or amplified speakers, the bass response rivals some of my tube receivers. There are even adjustable 8-band equalizer settings for audio to improve this even further.

In addition, Elecraft has unique audio effects available in the audio effects menu. One I’ve found very valuable in broadcast listening is called “delay,” a stereo simulation effect that broadens the mono sound in such a way that the audio sounds even richer.

Memories, scanning and tuning

The KX3 has 100 general-purpose VFO A/B memories with optional alpha numeric labels. It also supports channel-hopping or scanning within any number of labeled memory groups. Auto scan is simple and works in both muted and (my favorite) non-muted, or continuous, modes.

The KX3 can also use the “K3 Memory” application from Elecraft’s K3 transceiver, which allows for longer labels and the instant selection of desired memories from a PC. The “K3 memory” application is a free software download on Elecraft’s website.

The tuning knob on the KX3 is substantial and of good quality. It’s only slightly smaller than the tuning knob on my Alinco DX-R8T, so it’s a substantial knob, which is helpful to big (or buttery) fingers. The drag can be easily adjusted with a supplied hex wrench. The tuning rate can be adjusted to .5 kHz increments, allowing you to quickly tune through the band. The small multi-function knob next to the main tuning knob can also be set for a 1 kHz rate.

At first glance, you might not realize that the KX3 has a direct frequency-entry keypad. Check out the photo, however [MAKE REFERENCE TO POSITION ON PAGE]. The buttons and multi-function knobs in the lower left quadrant of the KX3 double as number pad, decimal point, and an “enter” button for a keypad. I thought this a bit odd at first, but now find I use this all the time.

Installing the optional ATU is very simple and requires no special tools or soldering

Optional ATU: Worth the Cost

As I mentioned earlier, the optional automatic antenna tuner, the KXAT3, makes a lot of sense for the ham who operates portable. If you are a licensed amateur radio operator, the ATU can be a powerful tool for matching random length, or multi-band antennas to your desired broadcast band by tuning to a nearby ham band frequency. The L and C parameters of the tuner can be manually adjusted to optimize without transmitting. The user can select one of 8 L’s or one of 8 C’s parameters in the ATU MD menu entry. When an L is selected, C is set to 0, and vice-versa. However, it is not presently possible to select combinations of L and C to achieve a closer resonance. Still, selecting an L or C value in this way will provide a useful increase in gain.

In addition, if you like medium wave (MW) DXing, the ATU comes with MW (AM broadcast band) filtering that tracks the VFO, somewhat improving image rejection between 300-1,000 kHz. I have tested the KX3 on medium wave both with and without the ATU installed and find that it certainly improves rejection.

To be clear though, sensitivity decreases as you tune below 1,500 kHz. Elecraft informed me that it was necessary because the KX3 uses PIN diodes in its T/R switch, and the signal must be high-pass filtered to avoid IP2 problems with the diodes. When you tune through the 300-1200 kHz range (or so) you will certainly notice the loss of sensitivity. Elecraft also noted that selectivity in the AM broadcast band was not a major design criteria, so in this band the 160 meter low pass filter is used. This is not ideal from a harmonic rejection standpoint, and there will be some 3rd and 5th-harmonic images from strong stations. Adding the ATU helps with this. However, adding the ATU doesn’t generally improve sensitivity in this range.

The ATU is very easy to install–almost “plug and play” (see photo).

Oh, yes–and it’s an SDR, too!

As if the KX3 didn’t do just about everything, it also has a quadrature down-sampling mixer compatible with PC-based SDR (software-defined radio) applications. This means, via a shielded stereo audio patch cable and a supplied USB control cable, you can connect the KX3 to your PC and use a freeware SDR application like HDSDR to turn your KX3 into a proper software-defined receiver.

SDR functionality is limited to receiver functionality, and depending on the bandwidth and sampling rate, will be dependent on the quality of your sound card. The true benefit is the ability to see a wide–48 kHz or more–chunk of spectrum.

Summary

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 some of my initial impressions. Here is the list I formed over the time I’ve spent evaluating the KX3. Note that I created this list with the shortwave listener in mind, not necessarily the ham radio operator.

I even had some success SWLing using an inexpensive whip antenna (attached via BNC).

Pros:

World class, benchmarked receiver performance powered by high-performance 32-bit floating-point DSP
Rich, full audio fidelity on AM despite limited bandwidth (see con)
AF and effective RF gain controls
Adjustable filters (no optional roofing filters needed for SWLing)
Superb sensitivity and selectivity; outperforming even my WinRadio Excalibur with weak signal DXing
Very low noise floor
Auto-notch, which helps eliminate annoying heterodynes, even in AM
Internal ATU option brings improved MW image rejection (see MW con) and hams have the ability to tune a random length antenna
Natively decode (170 Hz) 60-WPM RTTY and display it right on the KX3’s VFO B display, which is alphanumeric
Battery operation via 8 AA batteries
Lightweight
Dedicated headphone jack
For non-ham radio operators, the transceiver can be disabled and re-activated once you have a license with a simple hardware adjustment. No need to fear accidental transmission
For hams, or those who plan to become one, the KX3 is a QRP transceiver in the top of its class

Cons:

AM bandwidth limited to 4.2 kHz (see pro)
Hand mic connector is the less standard 3.5 mm audio plug
Built-in speaker is small with limited volume and fidelity–only intended as a back-up when headphones or external powered speakers are unavailable
AA batteries fit a bit tightly in internal holder and can present a challenge to remove
Medium wave reception is mediocre at best, but with the optional ATU, is improved though slightly better image rejection (see ATU pro)
Very slight audio whine (similar to a faint heterodyne sound) heard in some zero beat AM stations; may be fixed in future firmware update
No AM sync detector (AMS)

Did I buy one? Confession time

I must admit, I was appreciating my buddy Dave’s KX3 very much. Maybe too much…

I have three hobbies: shortwave radio listening, ham radio, and traveling. After using the KX3 for a few hours, I knew it would be my perfect companion. Not only is it a top-notch amateur radio transceiver, its also an excellent shortwave radio receiver. It’s portable, but also makes an excellent tabletop radio. It’s an all-in-one radio, but can also double as an SDR when connected to a PC.

So, is the KX3’s broadcast audio fidelity as good as a purpose-built broadcast receiver like the legendary Drake R8B? Not quite. But I would argue that its ability to receive weak signals would give even a Drake a run for its money. I have to admit, the KX3 receiver outperforms my Alinco DX-R8T in every respect. Even though the AM bandwidth is limited to 4.2 kHz, I think the audio also sounds better than my Alinco and any of my portable radios with wider bandwidth.

My Elecraft KX3 Transceiver (Click to enlarge)

Needless to say, I bought one. It was only fair to Dave, who needed to discover for himself what his loaned-out rig could do.

The KX3 is a game changer for me. Though I’ve always carried portable transceivers in my travels, I’ve also had to carry a separate tabletop receiver and an SDR or portable radio for my SWLing. No more. Moreover, I like the broadcast audio on the KX3 well enough to record and archive shortwave broadcasts, which I frequently do for my blog, The SWLing Post and The Shortwave Radio Audio Archive. In my shack, I’m even considering purchasing Elecraft’s 100 watt amplifier and doing away with my 100 watt tabletop transceiver.

As for support? No worries there. I’ve been an Elecraft customer for years and I can tell you that they believe in and stand behind their products. I purchased with confidence.

I encourage you to try on the KX3 as well. It may very well be all the radio you’ll ever need.

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A review of the Degen DE321 DSP shortwave radio

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This analog dial packs DSP!

The Degen DE321 is the first of a new type of radio hitting the market–a DSP-based receiver with an analog tuning dial. I was very intrigued by this radio since both it and the future Tecsun R-2010 are the newest of their kind. We’re still waiting for the R-2010 to hit the market, but the DE321 was introduced just a few weeks ago.

So, keep in mind that the DE321 I describe is not technically analog, although the dial and face appear to be.

Impressions

The Degen DE321 is slightly thinner than the Kaito WRX911.

My first impressions of this radio are very positive. The DE321 is small, slim, and fits nicely in the hand. While holding it the first time, I even noticed a small indentation where my index finger fits on the back of the radio underneath the telescoping whip antenna. Nice touch!

The DE321 also feels durable. It’s slightly thinner than the venerable WRX911–the radio I believe it best compares with in the analog world. It’s the first SW radio I’ve owned that can actually comfortably fit into the pocket of my jeans. Indeed, its size and form are fairly comparable to the typical smart phone.

For a very tiny built-in speaker, the DE321 has unexpectedly decent audio. In fact, it is easily superior to the WRX911–its tones are more mellow and there’s even a hint of bass response. I’m sure the DSP chip has been tweaked to produce audio suitable for this application.

The DE321 has a nice, sturdy back stand for tabletop listening. However, it takes quite a lot of pulling force to get it to pop out of its closed position; I keep fearing that I will break the stand when opening it up. For what it’s worth, I prefer this tension to radios that have floppy, lose back stands.

Tuning

The DE321 has a tiny red tuning light that works well when you receive a strong signal.

For a guy who was raised on analog tuning, yet now almost exclusively uses digital portables, the DE321 is a strange animal. When I first started tuning the radio, I noticed that the tuning wheel feels slightly “sticky.” At first, I thought the stickiness of the analog encoder was causing the tuning to skip over stations, as the action was not as fluid as most analog-tuned radios. Upon further investigation, I realized that it’s not the slightly sticky tuning wheel producing the tuning “skips,” rather, it’s the fact that the tuning is actually digital, thus I was hearing the “steps” between frequencies, which tricked my brain, translating into the sensory experience of wheel stickiness. Still, since the tuning wheel isn’t terribly fluid, I am not discounting some real frequency skipping at times.

I’m guessing that the steps are near 5 kHz on the shortwave bands, and that the single bandwidth is rather wide. The tuning steps on medium wave and FM seem to be appropriate for international use.

On a side note, the tuning experience is exactly opposite to that of the Grundig S350DL–an analog-tuned radio with digital display. The S350DL’s tuning feels sloppy and flexible, and the receiver is prone to drifting. The DE321, on the other hand, has a vague analog tuning display, but with precise, incremented tuning behind the scenes.

I’m pleased to note that the DE321’s stability is rock-solid and does not drift.

For casual band scanning, I find that the bandwidth and tuning steps are well placed. Happily, there is no noticeable muting between tuning steps.

Performance

The Degen DE321 with its older analog cousin the Kaito WRX911 in the background.

For this review, I compare the DE321 to the analog Kaito WRX911. The two have the same approximate size and price. In the near future, I’ll also compare reception with SiLabs DSP-based radios like the Tecsun R-2010 and the Tecsun PL-380. (Check back for these comparisons soon.)

On the shortwave bands, I feel that the sensitivity and selectivity are well-balanced. When I compare reception with the WRX911, the DE321 seems to pull in faint signals out of the murk a little better than the WRX911. However, I do notice some “pumping” as the AGC tries to cope with faint signals; it reminds me a bit of the Tecsun PL-310 in this respect. Sometimes I also notice that faint signals can range from being very faint to stepping up to clear and strong very quickly–the switch sounds like the DSP moving from not having enough signal to digest, to having enough to do its job. This can be a little frustrating as broadcasts may sound strong one minute, become weak within a fraction of a second, then pop back up again. I only observed this phenomena, however, when processing weak signals. Normal broadcast stations come in quite clearly.

Though I chose not to spend much time evaluating FM and AM (please comment if you have done so), I found the FM and AM (MW) performance to be on par with other radios using the SiLabs DSP chipset. I may expand upon this in the review later. (Update 16 Mar 2012: With more time spent on AM (MW) I realize performance on this band is sub-par–see comments).

Summary

Positives:

For a tiny speaker, the sound is surprisingly full
Sensitivity and selectivity are both good
Nice form–slim, and easily fits in the hand
Simple (see negative)
Inexpensive
Exceptionally wide FM bands (64-108 MHz) (see negative)
Unlike its analog counterparts, has absolutely no frequency drift

Negatives:

Back stand hard to pop open–though sturdy, it feels vulnerable as a lot of force is needed to open it
Tuning wheel feels slightly “sticky”
Absolutely no bells and whistles (see positive)
FM is in 2 bands, FM 1 and 2 (see positive)
AM (MW) performance is very weak
Though it looks analog, digital tuning produces slight “stepped” sound/ sensation, unlike the fluid experience of tuning a true analog radio

In conclusion, I think the DE321 is a great buy. It’s certainly a steal at $21 US, shipped. Though I simply find the idea of a rather vague analog encoder and display combined with the precision of a digital tuner a tad quirky–even backward–at the end of the day, the audio is very pleasant and the form perfect for slipping into your pocket.

I’m very eager to see how it stacks up against the soon-to-be-released Tecsun PL-2010. Stay tuned as I compare these in the near future…

Like most Degen (and Tecsun) radios, the DE321 is only available from eBay sellers in China/Honk Kong. I would normally call this a negative, since there is no real warranty for those of us living outside the country of origin. Still, I’ve been most impressed with purchases I’ve made from these highly-rated sellers. I believe they would help you if a problem were to arise and my experience is that they do a second QC (quality check) of their own, prior to shipping. The Degen DE321 in this review was purchased from eBay seller

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