Tag Archives: Tecsun PL-680

Mehdi discovers ESD protection in the Tecsun PL-680

The Tecsun PL-680

Many thanks to SWLing Post contributor, Mehdi, who writes:

Once you told me to be careful when attaching an external antenna to my portable radio.

Today I opened it to see whether it has some sort of protection on its external antenna path.

Tecsun-PL-680-Diodes

As you can see in the picture below, there are two diodes side by side (D4 and D2) which protect the radio’s front-end against high-voltage inputs.

Tecsun-PL-680-Diodes2

Description of what these two diodes do from http://www.giangrandi.ch/electronics/diode-clipper/diode-clipper.shtml:

“The basic idea of the diode clipper is that for signals with an amplitude within ±0.7 Vpeak (less than about +7 dBm over 50 ?) the diodes are just open circuits and do not interfere; for higher amplitudes, the diodes clip the signal to about ±0.7 Vpeak limiting the maximum power that reaches the receiver at about +10 dBm over 50 ?, which the vast majority of receiver circuits can easily tolerate. If you wonder why I specified +7 dBm for unclipped signals and +10 dBm for clipped ones of the same peak to peak amplitude, it’s because unclipped signals are supposed to have a nice sinusoidal shape; once clipped, they become more square and their RMS voltage is higher, explaining the 3 dB difference.”

Thanks for sharing this, Mehdi! I’m happy to see that the PL-680 has some built-in ESD protection.

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The SWLing Post 2015-2016 Shortwave Radio Buyer’s Guide

This article originally appeared in the November 2015 issue of The Spectrum Monitor magazine:


FourRadiosAbstract2

Despite the often-expressed view that shortwave may be on the decline, if one were to look at this year’s shortwave technology alone, the truth would seem to be anything but. Remarkably, 2015 has been a great year for the shortwave radio listener, as several models of portables, tabletops, and SDRs have been either introduced or improved.

The following is a basic, easy-to-follow buyer’s guide to some of the best receivers on the market currently. This guide is, by no means, comprehensive; rather, it’s a selection of rigs I have tested, some of which I now own. It builds on the guide I published in the November 2014 issue of TSM, and highlights innovations since that issue, while still acknowledging the contributions of previous models.

Compact/Travel portables

If your budget is tight, or if you’re looking for a radio that could easily slip into your glove compartment, backpack, carry-on, or even jacket pocket, you need to consider a compact shortwave radio.

Typically, there is a performance compromise with compact radios: they don’t always have the sensitivity of their more expensive cousins; they have a more limited frequency range; and they don’t detect single-sideband signals. Nonetheless, the ones listed here are fine performers for their size and price. Entries are listed in alphabetical order.

The Eton Traveller III

The Eton Traveller III

Eton Traveller III

Eton has once again refreshed the design of its popular “Traveller” series of compact receivers: their latest is the third edition, the Eton Traveller III. I’ve owned the past two versions of the Traveller, and having learned to appreciate these, was eager to get my hands on the newest Traveller III. As the name implies, this is a great little radio for the international traveler; it not only has shortwave, AM and FM bands, but it also has a world clock that can easily be switched from the front panel, a useful alarm function, and great built-in speaker. New to the Traveller III is FM RDS: a great way to capture FM station identification when visiting a new city. The key lock is prominent on the front panel and the included padded nylon case is one of the most rugged I’ve seen in years. Performance is what I’ve come to expect from the Traveller series: superb AM (mediumwave) reception, great FM reception, and capable shortwave reception. It lacks the multiple bandwidths found in other similar DSP radios, but my impression is that the default bandwidths are adequate for multi-band listening.

The Eton Traveller III is available from Universal Radio, Amazon.com and more outlets via Eton. Pricing ranges from is $55-60 US.

The C.Crane CC Skywave

The C.Crane CC Skywave

CC Skywave

Only a couple of weeks before the Christmas holiday of 2014, C. Crane introduced a compact portable that truly impressed me: the CC Skywave. The Skywave is as compact as any other ultralight radio, but adds a host of features that has made it an invaluable radio for my one-bag air travels. The CC Skywave covers the following bands: Shortwave, AM, FM, Weather, and Aviation. It’s a comprehensive toolbox of frequency bands and listening modes which only lacks, sadly, SSB.

Ergonomics are excellent for such a small portable. It’s easy to use, as well: I only needed to reference the well-written manual for a few functions. I find the CC Skywave to be very sensitive on shortwave and mediumwave, rivaling radios that cost much more.

One negative I’ve learned through readers of the SWLing Post is that the first production run of the CC Skywave was prone to overload in the presence of strong local broadcast stations. C.Crane have confirmed that this has been addressed in the latest CC Skywave production run and is no longer an issue. To insure you’re receiving a unit from the latest production run, consider purchasing directly through CCrane.

The CC Skywave is sold by Universal Radio, Amazon.com and directly by C.Crane. Price is $89 US.

The CountyComm GP5/SSB

The CountyComm GP5/SSB

CountyComm GP5/SSB (Tecsun PL-365)

CountyComm––a retail distributor of products created primarily for use by the US government––introduced a new shortwave portable late in 2014: the GP5/SSB. The GP5/SSB came about as a result of a large order CountyComm received from a US government department for an “inexpensive, small portable, AM/FM/SW radio with SSB” for emergency supply caches and diplomatic posts. Like its predecessor, the GP5/DSP, the GP5/SSB has a vertical form factor, much like a handy-talky, and a detachable/rotatable ferrite bar antenna that greatly improves AM/mediumwave reception. The GP5 series is limited by a small internal speaker that sounds somewhat tinny; it also lacks a direct entry keypad. Still, with a pair of headphones and some careful memory allocation, the GP5 is a pleasure to use.

If you’re looking for an ultra-portable radio with SSB, then the GP5/SSB is a very good choice. (It may, in fact, be the only ultra-portable SSB choice currently on the market). While the SSB performance can’t compare with larger, pricier receivers, or ham radio transceivers, it’s very good for $80 US. If you’re looking for an emergency communications receiver––something to stash in your vehicle, emergency kit, or bug-out bag––the CountyComm GP5/SSB is a great choice and value. Indeed, that’s who the GP5/SSB was designed for, and why this rig has excellent frequency coverage in all modes, with good sensitivity/selectivity and designed for portable, one-handed operation. In fact, CountyComm has even designed and manufactured (and in the USA!) a robust, protective 1000-Denier case for the GP5/SSB. This case makes it very easy to strap the GP5/SSB to your belt or backpack securely.

The CountyComm GP5/SSB is available from Universal Radio and directly from CountyComm.

The Sangean ATS-405

The Sangean ATS-405

Sangean ATS-405

I was surprised this year when Sangean introduced its latest compact/travel receiver, the ATS-405. I had heard rumors that Sangean may have been leaving the shortwave radio scene, so was pleased to learn that Sangean was not only still invested in the hobby, but innovating. Indeed, the ATS-405 has features that have not yet been included on small DSP-powered portables: specifically, the ability to control squelch, tuning mute, and soft mute.

The ‘405 is a decent little radio with a great deal of functionality and features for a rig in its price class. But overall, its performance seems 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 which plagued both of my review units. 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. I also found performance variations between my two review units; an indication that quality control is somewhat inconsistent at the factory.

The Sangean ATS-405 is available via Universal Radio and Amazon.com. Price is $89 US.

Other compact/travel radios

In the 2014 Buyer’s Guide we included several other compact travel radios worth considering: The [original] Kaito KA1103/Degen DE1103, Tecsun PL-310ET, and the Tecsun PL-380 to name a few.

Full-Featured Portables

In the portables market, I believe you get the most value and quality in the $90-250 price class. Most beginners and seasoned SWLs prefer a radio that includes everything necessary to get on the air immediately; all of these radios provide just that. Straight out of the box, you’ll have everything you need to listen to shortwave bands. All of these recommended radios are designed to pick up major shortwave broadcasters with ease, and offer the following features: good frequency coverage; circuitry that helps in the detection of weaker stations; and with a few notable exceptions, the ability to receive single-sideband.

The Tecsun PL-680

The Tecsun PL-680

Tecsun PL-680

The latest Tecsun full-featured portable––the PL-680––appeared on the market in February this year. Cosmetically, the receiver is nearly identical to the Tecsun PL-600, but with the added features of the Tecsun PL-660. Indeed, in terms of features and comparing them with that of the venerable PL-660, there are no obvious additions on the PL-680. The PL-680 has been improved, however, in its shortwave reception. The PL-680 is both slightly more sensitive and has a more stable AGC (Automatic Gain Control) than the PL-660. If you are primarily a shortwave radio listener and wish to have one of the best sub-$200 receivers currently on the market, the PL-680 may be the rig for you.

On the other hand, if you are primarily a mediumwave DXer and already own the PL-660, you will likely want to pass on the PL-680. The PL-680’s mediumwave reception is simply not as good as that of the PL-660. The PL-660 is both more sensitive and has a lower noise floor on mediumwave.

Note that since its introduction, inventory of the PL-680 has fluctuated; the primary retailer is Anon-Co in Hong Kong and on eBay. Price is $95 US (plus shipping from China).

The Eton Satellit

The Eton Satellit

Eton Satellit

Last year, Eton released the Satellit: a new full-featured portable, essentially replacing the venerable Grundig G3, but carrying the name of the flagship Grundig Satellit series.

The Satellit has many of the same functions as the Grundig G3, and has a near-identical form-factor, but sports a new amber backlit display, multiple bandwidths, and a double-jointed telescopic antenna. The Satellit performs admirably on the AM/mediumwave bands, quite well on the shortwave band but, most notably, performs brilliantly on FM. The audio fidelity from the built-in speaker is quite robust; indeed, it’s among the best in its class. The key layout and ergonomics are similar to the Grundig G3 and G5; meaning, the radio is quite simple to use. One negative is that the Satellit mutes between frequencies while tuning, however, this is minimal in the most recently-updated production runs. I’m very pleased that all of the new Eton radios lack the tactile rubber coating found on some previous models, for while the coating works excellently to improve one’s grip on the radio, over time it can become sticky to the touch (if you find this to be a problem, here are several techniques to clean the sticky residue: http://bit.ly/1KQN8TX).

At time of print, the Satellit is generally available for about $180-190 from a variety of retailers, including Universal Radio and Amazon.com.

Other full-featured portables

In the 2014 Buyer’s Guide, we included several other full-featured radios that are still certainly worth considering: The C. Crane CCRadio-SW, Sangean ATS-909X, Sony ICF-SW7600GR, Tecsun PL-600, Tecsun PL-660, and the Tecsun PL-880.

Hybrid Stand-Alone SDR/Tabletops

While tabletop receivers have started to decline with the advent of SDRs, there are many listeners who still prefer a simple, dedicated, stand-alone high-performance receiver with a good tuning knob and clear display, which is to say, a tabletop receiver. Tabletops are designed to perform best with a resonant external antenna.

The Elad FDM-DUOr

The Elad FDM-DUOr

Elad FDM-DUOr

If you’ve been thinking of purchasing an SDR, but really want a traditional front-panel tabletop receiver, the Elad FDM-DUOr may be for you. I’ve included the FDM-DUOr under the tabletop heading because it is, in fact, a tabletop receiver, with the features of a tabletop such as a front panel, knobs, display, and capability to operate independent of a PC. However, if you choose to hook it to a PC, you unleash a full-fledged SDR and a wide array of features. The FDM-DUOr is built on the same receiver and software as the FDM-S2, one of my favorite sub $1000 SDRs. The FDM-DUOr also sports 10 selectable and customizable filter preselectors and an internal switch box for use with an external transceiver.

At time of print, Elad is seeking FCC approval for the FDM-DUOr in order to distribute these units in the USA. The FDM-DUOr is currently available in Europe via the Elad online store: Price is 899.00 €.

The CommRadio CR-1a

The CommRadio CR-1a

CommRadio CR1-a

US-based manufacturer CommRadio introduced the CR-1 in 2013––an amazingly rugged, portable receiver, and essentially a small tabletop SDR. I’ve used mine in travels and at home; the built-in rechargeable battery will power it for hours, it’s built to a mil-spec standard, and it performs like a champ.

In 2014, CommRadio increased the SDR potential of the CR-1 by updating with a new model: the CR-1a. In 2015, CommRadio continued to add features to the CR-1a through firmware and software upgrades, such as a new Spectrum Viewer SDR application, and 3D-Waterfall for Windows PCs.

CommRadio CR-1a owners only need to update their firmware and download software to use the new feature. The CR-1a is priced at $599.95 US, shipped, and includes a battery through Universal Radio––good value for a quality piece of kit. CommRadio also sells the CR-1a directly through their website.

Other tabletops

In the 2014 Buyer’s Guide, we included several other tabletop radios, including the Alinco DX-R8T and the Icom IC-R75.

SDRs/IF Receivers

If you’re searching for maximum performance for the price, software-defined radios (SDRs) and IF receivers are hard to beat. These small “black box” radios require a computer to unlock performance, none are stand-alone. But while I was never a fan of combining my PC with radio listening, once I starting using an SDR, I never turned back. Now, 90% of the time that I’m on the air, it’s with an SDR. The ease of doing so is incomparable, and the functionality simply incredible.

The Elad FDM-S2

The Elad FDM-S2

Elad FDM-S2 and the new SPF-08 preselector

If you read the Elad FDM-S2 review in the November 2014 issue of TSM you’ll know that this little SDR packs a powerful punch for the price. FDM-S2 performance is uncompromising, comparing favorably to receivers $300-400 more in price. The S2 also provides native DRM decoding; it’s a fine DRM receiver.

Users who live in the vicinity of high-powered AM stations will be pleased to know that Elad has developed an outboard preselector box that pairs with the FDM-S2––the new SPF-08, which covers the amateur radio bands. Elad already has a broadcast band version of the SPF-8 in development. The SPF-08 enclosure is the same size as that of the FDM-S2 and couples with it directly via a port on the back of both units.

Both the Elad FDM-S2 and SPF-08 are available via Elad’s online store: http://ecom.eladit.com/

The SDRplay RSP

The SDRplay RSP

SDRplay RSP

The SDRplay RSP was one of the most pleasant surprises I encountered in the world of software defined receivers this year. I published a review of the RSP in the May 2015 issue of TSM; in short, I was amazed at the performance of this $149 SDR. While it doesn’t have its own proprietary SDR application, it is compatible with some of the most popular free applications on the market: SDR Console, SDR Sharp, and HDSDR to name a few. SDRplay developers are even testing a Raspberry Pi application for the RSP.

Since the time of my review, SDRplay has updated the RSP to include gapless coverage from 100 kHz to 2 GHz––talk about wideband coverage!

If you have been hesitant to invest in a benchmark SDR, or simply want to explore the world of SDRs on a small budget, the SDRplay RSP is a no-brainer. Without a doubt, it packs a lot of performance in a tiny, affordable package. The SDRplay user community is also very active and routinely pushes the boundaries of this little receiver.

The SDRplay RSP is available at SDRplay.com and, in the US, at Ham Radio Outlet.

The RFspace Cloud-IQ

The RFspace Cloud-IQ

RFSpace CloudIQ

The Cloud-IQ is the latest software-defined receiver from the US-based company RFSPACE. The Cloud-IQ offers two modes of operation:

  • the “IQ mode,” which provides 24-bit IQ streaming to your PC over an ethernet cable (much like the RFSpace NetSDR).
  • the stand-alone “cloud mode,” which includes a built-in internet server. In cloud mode, according to RFSpace, “the receiver performs the tuning and demodulation of signals and transmits the demodulated information back to a PC, OS-X, Linux, or Android client anywhere in the world.”

RFSpace is essentially one of the first SDR manufacturers to include built-in SDR streaming functionality, something that has been somewhat complicated to implement in other SDRs.

The price point is also favorable at $629.95 through Ham Radio OutletAmazon, Astroradio and ML&S. Availability has been quite limited this year, but more production runs are planned for the near future. I plan to review the RFSpace CloudIQ in late 2015 or early 2016, as soon as a unit becomes available.

Other SDR/IF receivers

In the 2014 Buyer’s Guide we included several other SDRs and IF receivers worth considering, including the Bonito RadioJet IF-Receiver 1102S, Microtelecom Perseus, and the WinRadio Excalibur. Additionally, note that the affordable Airspy SDR will soon have a new converter to cover HF down to 1kHz–look for a review in 2016.

The Shortwave Radio Index

If you would like to view a comprehensive list of all shortwave radios currently on the market, check out the Shortwave Radio Index (http://swling.com/db).

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Universal Radio: Used Tecsun PL-680 for $69.95

Universal-Radio-Used-Tecsun-PL-680

I just noticed that Universal Radio is featuring the following used Tecsun PL-680 in their used receiver collection. Here’s the description:

The Tecsun PL-680 receives longwave, AM, FM and SW bands plus VHF Airband. It features a backlit digital display, stereo FM (to ear jack), SSB, clock timer, 2000 Memories, Sync. Detection, ATS and keypad entry. The left side features earphone, external antenna and input voltage jacks. The right side features a variable BFO and tuning knob. The rear panel has a battery compartment for 4 AA cells (not supplied). This PL-680 system includes: box, nice carry case, printed manual and earphone.

The price is $69.95 plus shipping–very reasonable, in my opinion. The best part is Universal Radio offers a reputable 60 day warranty with all of their used items.

I regularly check Universal’s used and demo list. Occasionally, great bargains pop up and I feel I can always buy from them with confidence as they check over each item before posting.

Click here to read our review of the PL-680.

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PL-680 and ATS-405 radio reviews now online

PL-680-BBC-Click-FrequencyThis week, both Jay Allen and Chris Freitas have reviewed the Tecsun PL-680. If you’re considering purchasing a PL-680, you should check out both reviews and also our PL-680 review and radio comparison from February.

Jay has also reviewed the Sangean ATS-405 on his website and Keith Perron tells me he will include a review of the ATS-405 on today’s episode of Media Network Plus. Keith has informed me he was very disappointed with the ATS-405, but Jay’s review is mostly positive, focusing on its great AM (medium wave) performance and new tuning/muting functions.

This is certainly the week for reviews!

On that note, Universal Radio is kindly sending me a loaner Sangean ATS-405 for review. I hope to compare it with some other benchmark portables in the next few weeks. Follow the tag ATS-405 for updates.

Click on the following links to check pricing for both the PL-680 and ATS-405:

Tecsun PL-680

Sangean ATS-405

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Tecsun PL-680: SSB display inaccuracy

PL-680-Sync-Detector

SWLing Post reader, Olli Turunen, writes:

I thought you would like to know this. I bought PL-680 few days ago and I noticed that mine has the display about 1 khz off. I contact Anna on Anon-Co and got a quick reply:

“I have received a response from the supplier regarding the 1 kHz deviation issue of the PL-680 radio. Unfortunately they consider this to be within their tolerance standards for SW reception. Overall, their standard is set to be +/- 0.5 kHz, which translates to 1 kHz on the LCD display. They understand the effect it may especially have for SSB listening, which is why fine tuning has been added as a feature.

For MW/AM the situation is a bit different. According to the supplier this is an issue that both the PL-680 and PL-660 radios have and cannot be avoided. As they indicate, unfortunately only the PL-880 has a special function for MW frequency calibration.”

I just checked my PL-680 and did a zero-beat in SSB against WWV on 10 MHz. If the BFO adjustment is correct when in the middle position, I can confirm that mine is almost 1 kHz too high as well.

For AM listening, a 1 kHz deviation isn’t noticeable.  If you’re using ECSS, though, you’ll certainly have to fine tune the BFO accordingly.  If locating a CW or SSB signal (in the ham bands, for example), you’ll also need to adjust the BFO fine tune control in advance.

Most importantly–and fortunately–when you turn on the PL-680’s synchronous detection, the receiver is exactly on frequency (at least on my early model PL-680).

Many thanks, Olli, for sharing this information! I’ll note this negative in the PL-680 review.

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A review of the Tecsun PL-680 with reader survey results

Tecsun-PL-680When I heard early reports about the new Tecsun PL-680, I was already wondering how it would stack up alongside other Tecsun portables. An early photo of the Tecsun PL-680 revealed how very similar it is, indeed, to the Tecsun PL-600, which has been on the market for many years. Moreover, the features of PL-680, which I heard about only a few weeks ago, sounded to me like a carbon copy of the venerable PL-660.  I investigated further, and spoke with Anna at Anon-Co; she was given to understand that the Tecsun PL-680 was essentially a re-packaged PL-660 with improved sensitivity. I was curious enough about the PL-680 that I ordered one from Anna as soon as they were available, even paying for expedited shipping in order to have it in hand a bit sooner.

The Tecsun PL-660 has been on the market for several years now; it’s one of the most popular shortwave portables on the market.  And for good reason: the PL-660 is relatively inexpensive, simple to use, packs all of the most vital and desirable functions/modes, and is available from a variety of retailers that ship worldwide. I have reviewed it numerous times and often used it as the basis for comparison with other shortwave portables. It’s China-based manufacturer, Tecsun, has emerged over the past few years as the dominant manufacturer of shortwave radios.

First impressions

I posted a few unboxing photos the day I received the PL-680.

Tecsun-PL-680-6

The Tecsun PL-680 looks like the Tecsun PL-600 body, with the Tecsun PL-660 features and layout. Indeed, the full complement of buttons, switches and dials are identically positioned to those of the PL-660.

Let’s cut to the chase…

Question: So, does the PL-680 have more functions than the PL-660?

Answer: No. It appears to be, and likely is, identical in every (functional) respect to the Tecsun PL-660. No surprises here, unless there are hidden features I haven’t discovered…!

Check out the following comparison photos–the PL-600 on the right, PL-660 in the middle, PL-680 on the right (click to enlarge):

DSC_0187

RightSide LeftSide

The similarity is so striking, in fact, that I believe the PL-680 is the first radio I’ve ever turned on for the first time, only to find I immediately knew every function. I’m so familiar with the PL-660 that I could even use the PL-680 in the dark the first night I used it.

It also helps, of course, that the PL-680 is nearly identical to the PL-600, too, which I’ve owned for many years.

PL-600

Here’s how I see the PL-680 product development equation:

PL-600-PL-660-PL-680

In truth, I was quite disappointed that Tecsun did not add a line-out jack to the PL-680.

The PL-660, alas, lacks line-out, and though my Tecsun PL-880 has a line-out, its default shortwave volume is simply too high to be used by most digital recorders. I had hoped that the PL-680 might have a proper line-out jack, potentially making it a replacement for my trusty Sony ICF-SW7600GR.  Unfortunately, this is not the case.

But other than missing a line-out jack, I really have few complaints. I’ve always been a fan of simple radio design and I believe Tecsun has done a good thing by keeping the user experience so similar in their PL-6XX line of portable shortwave radios. Apparently, a good thing is a good thing.

But here’s what everyone wants to know…

Question: Does the PL-680 have any performance advantages over the PL-660?

Short Answer: Yes! (But keep your PL-660.)

I should add here that I’m about to get rather technical and radio-geeky, so if you’re only interested in a summary, please skip to the bottom of the page.

Otherwise, help yourself to a cup of coffee, and let’s talk radio…

Shortwave performance

Since I spend 95% of my listening time on shortwave, I’ll begin with shortwave performance. Again, we’ll compare the PL-680’s performance with that of the PL-660.

Reader survey results

Having had such great results from radio comparison shoot-outs in the past (check out our shoot-out between top portables and ultra-compact radios), I decided it would make sense to invite our informed readership to evaluate the PL-680’s performance in a series of blind, informal tests. (For information about these surveys, please read through the first of the three surveys.)

Shortwave AM broadcast listening

In most circumstances, you’ll find that the PL-680 has better sensitivity than the PL-660. It’s a marginal improvement, but one I certainly notice on the shortwave bands–and so did the majority of readers who participated in the shortwave AM reception survey.

The survey had recordings from a total of three broadcasters: Radio Prague, WWV, and Radio France International.

The PL-680 was “Radio A,” and the PL-660 was “Radio B.”

The Radio Prague recording was quite strong and was the only broadcast in our survey in which the PL-660 and PL-680 ran neck-and-neck.

Radio Prague on the PL-680

Radio Prague on the PL-660

In truth, I believe strong signal reception on both these radios is excellent and nearly indistinguishable from each other.

Survey results from the WWV and Radio France International recordings showed a strong preference for the Tecsun PL-680. Again, here are the original recordings:

PL-680 – 1st WWV recording

PL-660 – 1st WWV recording

PL-680 – 2nd WWV recording

PL-660 – 2nd WWV recording

Based on comments from those who participated, the PL-680 came out ahead of the PL-660 in two respects: better sensitivity, and more stable AGC. In both sets of recordings, the signal was weaker than the Radio Prague recording, and QSB (fading) more pronounced. Herein lies a well-known weakness of the PL-660: soft muting and a sometimes over-active AGC equates to more listening fatigue.

Here is a chart with the full survey results based on 194 listener reports. The number of responses are represented on the vertical axis.

AM-SW-Shootout-PL680-PL660

Obviously, the engineers at Tecun addressed the soft muting/AGC problem of the PL-660. In all of my time with the PL-680 on the air, I haven’t noticed any soft muting; the audio has been smooth and the AGC copes with fading much better than the PL-660. No doubt, these two improvements alone make the PL-680 a worthy portable for shortwave radio listening.

There is a downside to the improved sensitivity, however: the PL-680 has a slightly higher noise floor than the PL-660. This is mostly noticeable during weak-signal listening. Though I haven’t compared it yet, I’m willing to bet that the noise floor is comparable to that of the Sony ICF-SW7600GR. Personally, if increased sensitivity and stability means a slightly higher noise floor, I’m okay with that. I find that I listen better when the signal is stable and not fluttering/muting with every QSB trough.

Synchronous detection 

PL-680-Sync-Detector

The second survey focused on synchronous detection, which is a very useful receiver tool that mitigates adjacent signal interference and improves a signal’s stability. Perhaps it was my good fortune that the same day I tested synchronous detection, fading on even strong stations was pronounced at times. Perfect!

The first recording set was from Radio Australia, a relatively strong signal here in North America. Still, QSB was pronounced–making for an unstable signal–and there was hetrodyne interference in the upper sideband of the broadcast. When I switched the radios into lower sideband sync, halfway through, it effectively mitigated the hetrodyne in all of the recordings.

PL-680 – 1st recording Radio Australia

PL-660 – 1st recording Radio Australia

PL-680 – 2nd recording Radio Australia

PL-660 – 2nd recording Radio Australia

The second set of recordings were of Radio Riyadh–a much weaker station–also affected by QSB:

PL-680 – 1st recording Radio Riyadh (wide band filter)

PL-660 – 1st recording Radio Riyadh (wide band filter)

PL-680 – 2nd recording Radio Riyadh (narrow band filter)

PL-660 – 2nd recording Radio Riyadh (narrow band filter)

While I have always considered the PL-660 to sport one of the stronger sync locks in current production portables, it did truly struggle to maintain a lock in both the Radio Australia and Radio Riyadh recordings. Indeed, I was so surprised by how comparatively feeble the sync lock was on Radio Australia, that I disconnected the PL-660 from the recorder and moved to a different location to verify that something nearby wasn’t causing the sync lock instability. It was not; it was solely due to unstable band conditions.

It came as no surprise that survey respondents took note of the PL-680’s stronger sync lock: the PL-680 beat the PL-660 by a wide margin in both sample recordings. I chart the results, below, from a total of 85 responses:

Syn-Lock-Shootout-PL660-PL680

Very good, PL-680!  Someday I’d like to compare the PL-680 with the Sony ICF-SW7600GR, which I’ve always considered to have, among current portables, the strongest sync lock.

Single Sideband

I wasn’t able to provide an audio survey of SSB performance since the PL-680 picked up too much noise from my digital recorder to make for a fair contest.

Meanwhile, I’ve spent time listening to both radios in SSB mode and comparing the models. To my ear, both are very close in SSB performance, but again the PL-680 does have a slight edge on the PL-660 in terms of sensitivity and AGC performance.

SSB audio fidelity is very similar in both radios.

FM Performance

While I haven’t spent more than, let’s say, an hour with the PL-680 on the FM band, I have concluded that it is very sensitive–able to receive all of my benchmark local and regional FM stations.

An informal comparison between thePL-680 and the PL-660 also leads me to believe that they are both excellent FM performers and seemed to compare favorably. I would certainly welcome FM DXers to comment with their own evaluations of the PL-680.

Medium Wave Performance

Tecsun-PL-680-MW

I’ve also posted a medium-wave listener survey since many of you asked that I provide an evaluation of the medium-wave band.

In short, here is where the PL-680 loses to the PL-660: whereas, on the shortwave bands, the PL-680 is more sensitive,  it lacks the same sensitivity on the medium-wave bands.

Though I believe the PL-680 does a marginally better job than the PL-660 of handling the choppy conditions of nighttime MW DX, the PL-660 still pulled voices and music out of the static and made them noticeably more intelligible.

The survey result swung very hard in favor of the PL-660, which has long been one of the more notable medium-wave performers among shortwave portables.

I provided a total of four sample broadcast recordings for comparison. Below, I have embedded one of them–a recording of 940 AM in Macon, Georgia, for your reference.

PL-680 – 940 AM

PL-660 – 940 AM

You can listen to all four recordings in the original survey (again, note that Radio A is the PL-680, B is the PL-660).

Survey results were definitive, with a total of 116 responses:

MW-Shootout-Results

 

In all but the strong station sample (750 AM – WBS Atlanta), the PL-660 was preferred by a wide margin.

Summary

Invariably, all radios have strengths and weaknesses; here is a list of my notes from the moment I put the Tecsun PL-680 on the air:

Pros: 

  • Excellent sensitivity and selectivity on the shortwave bands
  • Improved weak signal stability over the PL-660
  • Stable sync lock
  • Proven PL-600 form factor with good overall ergonomics
  • Great internal speaker–an improvement over the PL-660 (but not as good as the PL-880 or Sangean ATS-909X)
  • Other than medium-wave performance (see con), a worthy replacement for the PL-660
  • Excellent audio from the PL-680 internal speaker (improved over the PL-660, but not matching the fidelity of the PL-880)

Cons:

  • Medium-wave performance for is a step backwards from the PL-680’s predecessor, the PL-660. Okay on strong and moderate-signal reception, somewhat poor for weak signals
  • Marginal noise floor increase on the shortwave bands
  • Like the PL-660, lacks a line-out jack (Please note this, Tecsun!)
  • SSB frequency display on my unit is + 1 kHz, slight BFO adjustment is needed (details in this update)

Conclusion

Tecsun-PL-680-MWIf you’re a shortwave radio listener, you’ll be pleased with the Tecsun PL-680. In all of my comparison tests between the Tecun PL-660 and Tecsun PL-680, the PL-680 tends to edge out the PL-660, performance-wise. This coincides with the user surveys, too.

If you’re a medium-wave DXer, you might skip over the PL-680. That is, unless Tecsun makes a good iterative design improvement. If you’re a casual medium-wave listener, on the other hand, you’ll probably be pleased with the PL-680.

All in all, I like the Tecsun PL-680 and I see myself using it more than the PL-660 when I’m on the go. If you’re primarily a shortwave radio listener, the PL-680 may very well be worth the upgrade. At $95 US plus shipping, it is certainly a good value. Note that Anon-Co plans to post the Tecsun PL-680 for sale on eBay in March 2015.

Click here to find the PL-680 on eBay.

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Tecsun PL-680: Reader surveys closing today

TecsunPL680andPL660

If you haven’t had a chance to weigh in on the Tecsun PL-660/PL-680 comparison surveys, you will need to do so by 23:00 UTC today.

I’m working on the Tecsun PL-680 review and need completed surveys for graphs/charts. The review should be posted this weekend.

If you haven’t voted yet, here are links to each receiver survey with comparative audio samples:

Responses for these surveys has been, quite frankly, amazing! At time of publishing this post, we’ve received 367 individual survey responses! Thank you!

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