Tag Archives: Tecsun

A review of the Tecsun R-9012 shortwave radio

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Many thanks to SWLing Post contributor, Laurence Neils, who shares the following guest post:

A review of the Tecsun R-9012

by Laurence Neils

I have cheap radios. I can’t really justify buying more expensive ones given how much time (not all that much) I spend listening to the short wave broadcasters. The consequence of this is that, when I do listen to shortwave stations, I have the rather standard ultraportables to listen on.

My go-to radio is the Tivdio V-115, which has pulled out quite nice reception for me, and offers several functions I like a lot. However, it was missing one that interested me the most: analog or analog-like tuning. If I want to listen to something, I either have to know its frequency and try it, or I have to let the radio do an automatic scan. While it’s quite good at pulling out stations and letting me hear them, it can take a few minutes to do a full scan, and canceling it doesn’t result in the part scanned so far to be stored. Very few stations I am interested in hearing are convenient to jump into several minutes after they start (my interest is in spoken content rather than music, and neither news nor stories make a ton of sense if the introductory information was not heard).

From a recommendation here on the SWLing Post, I chose to purchase a Tecsun R-9012 radio to help me do a convenient scan, which is useful because it allows me to find stations without knowing their frequency, and leaves me to not remember all seventy frequencies a certain broadcaster is using this year.

Physical Description

When I bought my Tecsun R9012, it arrived quite quickly from Amazon. It included a short manual, whose contents could be loosely paraphrased as “insert batteries and turn on”. Other than that, the radio is all that’s there.

The R9012 is relatively small, but not as thin or compact as the Tivdio, which will be my main comparison unit for this review. It is your basic rectangle form factor, and about the size of the small tape recorders that were the last to be phased out for portable recorders. It would be easy enough to put this in a backpack, jacket pocket, or glove compartment, but you have no chance comfortably fitting it into a standard pocket. On the back, there is a flip-out kickstand that can hold the radio at about thirty degrees from horizontal and the battery compartment. This radio is powered from two AA batteries.

The right side of the R9012 contains the analog tuning knob, which I will discuss quite a bit later, and the power switch, which is not connected to anything else (not integrated into the volume knob or mode selector).

The left side gives you a 3.5mm audio out jack. This supports all the headphone types I’ve tried. One benefit of this radio is that headphones with integrated microphones, such as the ones that come with the iPhone as well as various sets that are intended for phone use, will work with it. Some other radios won’t work well with that type of headset. The Tivdio, for example, will play through the headphones but forgets to turn off the speaker if there is a microphone on them, making the headphones pretty much pointless.

Next to that jack is a power port, supposedly to recharge the batteries. A connector for this is not included, nor do they seem to sell one. I suppose the theory is that you might already have a suitable one in that box of old cables we all have, but I can’t see this as a particularly useful feature given the RFI you’ll get if you connect a radio directly to the mains to recharge. Above the ports is the volume knob, which is a very basic analog one, and then the wrist strap, which is integrated into the case. There doesn’t seem to be a way to remove or change it, should you desire that.

On the front of the radio, the speaker takes up the left half. This is fine for standard listening, but don’t expect wonders of audio fidelity. On the right half, there is the twelve-position mode switch (from left to right, FM, MW, SW from low to high frequency) and the tuning display.

FM performance

The Tecsun has a standard FM function, with stated coverage from 76 to 108 MHz. This is the leftmost position on the mode selector. The band is not divided into multiple switch positions, meaning that stations will be relatively packed into dialing space when compared to shortwave, which is spread across ten bands.

I didn’t buy this radio to use it for FM. I have very little interest tuning for FM stations. Some people may enjoy the experience of manual tuning for a station they can locate quickly, but I’m not one. I can easily type the frequency I want on my Tivdio, and I intend to keep doing that for FM. I mostly intended to test FM performance on the R9012 because I was curious to see whether there would be anything audible in the 76-87 MHz section. I know that our TV standards have switched off using analog audio, so I assumed there would be nothing, but I’d never formally put that to the test.

FM on the R9012 has problems. In fact, it has a lot of problems. Among other things, the FM process on this radio doesn’t seem to have a very good idea where things are. I’d be tuning through looking for some station and I’d find it…only to see that I was in a completely foreign part of the spectrum where that station had no business being. It seems that, unless you’re very focused in on a station, the R9012 is liable to pick up some other broadcast and layer them on top of each other. Never mind that the broadcasts have nothing to do with each other and aren’t anywhere near each other on the band. If you have a specific station you want, you can tune to it and have no problems. If you want to see what’s there, you’ll have a very fun time listening to stations that you might want to listen to, only to find that that was an image, you’ve lost it now, and you can’t find it again.

Sometimes, I managed to find a part of the spectrum that gave me three different images simultaneously. Ironically, the broadcast I intended to use as my landmark, the local classical music broadcast, which is located very close to the middle of the FM spectrum, was strong enough or at a coincidental frequency that I identified images of it at six different places on the scan, in addition to where it should be. So I got my answer about 76-87 MHZ. According to the R9012, there’s a lot of signal there. It’s just coincidence that it sounds exactly the same as standard FM broadcasts with extra static.

FM performance gets worse: this radio is extremely sensitive to location.

In order to get nice reception, you have to have the radio in a good position. This seems to be completely random. Standing up so the antenna lies flat on the top, but is not extended produces almost silence. Lying down so the antenna is touching the table (not a metal table) or chair (not a metal chair) causes most signals and images to come through quite clearly. Extending the antenna to medium length helps reception. Extending it all the way introduces a lot of interference. On FM, volume also changes a lot. We may reasonably expect for the signal to change if we connect something conductive to the antenna by, say, touching it with our conductive fingers. Maybe reception will get more static, or maybe it will in fact improve. What we don’t expect is for the broadcast to switch from comfortable volume to let’s see if we can get you some tinnitus volume. Unfortunately, that’s sometimes what happens on FM if you touch the R9012’s antenna. Or tilt it a bit in the wrong direction. This doesn’t seem to happen much if it is tuned onto a station, but if it is anywhere in the middle or if there’s some static, the volume change is very noticeable, in that it makes you want to get the radio off as soon as possible.

In summary, this radio just can’t really do FM. If your other radios are broken, you’ll be fine by using this, but don’t buy it if you intend to do FM things.

Mediumwave performance

The MW frequencies are mostly there, with stated specs including from 525 to 1610 kHz. While there are broadcasts between 1610 and 1710 KHZ, that’s not a ton of the spectrum. I don’t have much interest in MW. I tested the radio’s performance, and it seems fine. Strong stations come in loud and clear. Stations that have low broadcast powers are easy to tune in. I was able to get some skywave MW in here as well, but I really don’t have any interest in that. I was able to verify, however, that the terrible effects that plague FM performance don’t appear on MW. I got no images of distant stations, no rapid volume switches, and the position of the radio doesn’t seem to affect MW reception all that much. Perhaps this is due to the different antenna that most radios employ in tuning MW. However, the manual doesn’t say whether this radio has such an alternative antenna and I haven’t gone to the effort of disassembling it to find out.

Shortwave performance

Once again, the crazy stuff seen on the FM band doesn’t appear during shortwave listening. I was able to tune in quite a few stations, although this probably isn’t a DX-capable device unless you’re willing to go out into RFI-free areas. That sounds enjoyable, but it’s not really my thing. When I got signal, it came in quite clearly. I got very little interference from the device itself, although it does seem quite susceptible to RFI from power lines. Of course, so is everything else, but if you put its antenna closer to a line, you’d know it.

Frequency coverage

Shortwave is covered in ten bands that allow access to the more populated areas of the spectrum, but have many gaps. Certain descriptions claim that the radio has coverage from 3.90 to 21.85 MHz. This is so misleading I’d be willing to call it a lie. The actual ranges are as follows:

  • SW1: 3.7 – 4.10Mhz
  • SW2: 4.75 – 5.06Mhz
  • SW3: 5.95 – 6.20Mhz
  • SW4: 7.10 – 7.30Mhz
  • SW5: 9.50 – 9.90Mhz
  • SW6: 11.65 – 12.05Mhz
  • SW7: 13.60 – 13.80Mhz
  • SW8: 15.10 – 15.60Mhz
  • SW9: 17.55 – 17.90Mhz
  • SW10: 21.45 – 21.85Mhz

So what if most signals are in there somewhere? Those gaps are very large. For example, the only broadcast frequency for WWV that would be covered on this set is the 5MHZ one. 10, 15, and 20MHZ are all located in various gaps on the bands.

This turned out to be quite annoying. I know that these are standard areas of the spectrum, in which people place a preponderance of broadcasts, but the fact remains that a lot of broadcasts occur between the bands on this set. I checked the A18 shortwave schedule to identify how crazy I was. Of the 5530 broadcasts that were listed between the limits of 3.90 to 21.85 MHZ, 1870 of them or 33.8% of the total, are outside the range of this set.

It strikes me that the largest band on this radio covers only 500 kHz of space, whereas the smallest gap between bands covers 750 kHz. In many cases, bands cover only 100 kHz of bandwidth. While I guess it’s better that they’re there rather than their being completely absent, perhaps some effort could have been done to open that up a bit more. I quickly analyzed where missing signals were, and if Tecsun could extend the 5.95-6.20 MHz band down to 5.8 MHz, 7.10-7.30 up to 7.60 MHz, expand the 9.5-9.9 band, and give an extra 50 kHz to the 11.65-12.05 band, most of the missing spectrum, nearly a thousand broadcasts, would be brought back into coverage. This could be done and still keep the maximum band width at 500 kHz. Therefore, as they didn’t seem to feel this an important issue, it falls to me to consider it so.

Manual tuning

So I bought this to tune manually. It stands to reason that I should review how well it does that.

The analog dial is on the right, and protrudes outward. Once again, the knob does its job, but not all that well. It was very easy to use this to pan through the spectrum and pick up stations, but the wheel doesn’t make it all that easy to do so quickly. You have to turn it by grasping, as the wheel has a fair bit of resistance. I don’t doubt that this feature helps to keep from knocking it off frequency, but you have to use two fingers to rotate freely, and that slows the process down. Meanwhile, the wheel has a rather disconcerting way of stopping, where the wheel seems to have hit an obstruction. However, this essentially increases the resistance, rather than feeling like a barrier. It’s noticeable, but it feels like something’s blocking the turning mechanism, rather than that the mechanism has reached its limit. Actually, it is possible to keep turning the dial, which I assume will eventually damage something, but if you’re not used to how it feels, you may do so without realizing that you’re not actually going anywhere.

The wheel has quite a bit of travel. On my set, it will rotate about three full turns. I believe this is necessary because all of FM, including the standard and Japanese bands, is in one section. Therefore, the wheel needs to be able to turn a lot in order to separate those stations. However, this means that panning over a shortwave band that covers at most 500 kHz of spectrum includes a great deal of panning over static. This works to scan quickly, but there are undoubtedly even faster ways to do so.

Conclusions

It’s a radio. It will pick up stations and make noise. In that, it works. However, this isn’t exactly a great set. The $22 price tag may forgive some of its flaws but not all of them.

Radios like the Tivdio models cost similar amounts and cover the spectrum more fully with some extra features. When I purchased this model, I expected the lack of features to be made up by convenient scanning over shortwave, relatively good sound, and relative disposability. I got enough for me to keep the set, but nothing more.

Pros:

  • Mediumwave is rather sensitive for those who enjoy listening to those signals.
  • Radio has a kickstand and the antenna can be rotated freely.
  • Radio supports headphones with inline microphone.

Cons:

  • FM is plagued by images of other stations that should not be there. This is rather bad.
  • FM is far too sensitive to antenna position.
  • Shortwave coverage, while it includes most of the spectrum in use, has big gaps that are actually being used by a lot of broadcasters.
  • Analog tuning works, but not really well. The knob can turn but does so with effort.

Would I recommend people to purchase this? Probably not.

Those who have higher-priced devices will get nothing from this. Those getting into the hobby aren’t going to get a ton of benefit from this, because tuning on shortwave requires enough familiarity with dial position that they may spend too long figuring it out. It would be useful on FM only if most other radios have been broken. It’s not even that good as an emergency set because of the FM sensitivity problem.

If all you want is analog tuning over the bands that are provided, the radio will do it for you. If you want more, buy something else.

Thanks for sharing your evaluation Laurence. Thanks for focusing on one of the points that is often overlooked with analog radios: the frequency coverage on various shortwave bands. The R-9012 does seem particularly segmented. 

Tecsun R-9012 retailers:

Post readers: Do you own the R-9012? What are your thoughts? Please comment!

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The Professor reviews the RFA200 external ferrite antenna

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Many thanks to SWLing Post contributor, The Professor, who shares the following review of the RFA200 external ferrite antenna:

The Tecsun R-9012 and RFA200 MW antenna (Photo credit: The Professor)

A Quick Review of the RFA200

The Professor

I’ve considered saying something here about RFA200, as I bought one of these not long after its existence was announced on this blog a few months ago, but I’ve been hesitating because I didn’t have much good to say about it. A couple of times I’ve placed it up snug up against the the top of the two Tecsun sets I have handy (the PL-310ET and the PL-880) and found that despite a lot of knob turning it had little or no effect on improving signal on medium wave stations. I was not impressed.

But I guess I’ve kind of changed my mind on that. And oh yeah, I bought another radio. It’s funny how you can talk yourself into things when you’re talking someone else into something. But after I had mentioned to a reader here the other day that the very inexpensive Tecsun R-9012 was a worthy analog DX portable, I decided to drop twenty and pick one up for myself. After all, it was about the same price as a fancy Brooklyn hamburger. It arrived a couple days ago.

So, I have been playing with it a bit over the last few days. It’s as good as the other ones I’ve had which are the same basic radio (I’d mentioned that the bandswitch slider broke in a couple of mine). It’s single conversion. The bandwidth is a little wide, but it’s a very sensitive and simple analog set.

Yesterday I was going through the AM band and remembered that ferrite from Greece, and I pulled it out recalling that in my experience some radios are more susceptible to reception improvements using passive loops than others. Maybe this ferrite bar might be similar. And sure enough, the antenna made a notable difference this time. By placing it up against the R-9012 and tuning the thing I could certainly increase signal a bit. And I could even see it in the slight brightening or steadiness of the tuning light.

So, not a total waste money after all. I would emphasize that the difference in reception doesn’t seem to be as dramatic or sustaining as you might hear with a tunable loop antenna next to your radio. But it’s not junk either. Then again, for fifty dollars shipped it is a little pricey. Twice as much as a Tecsun tunable loop antenna, and two and half times more expensive than the R-9012 itself.

I found the best way to use this antenna is to tune the radio separately first and when you find a weaker signal you want to improve physically go ahead and rotate the radio until the signal is strongest and THEN put the antenna along the top of the radio and adjust the tuning knob on the antenna. Focus in on strengthening the signal you actually hear, going back and forth until it gets strongest. If you seem to be pulling up other stations it’s because the antenna adjustment will bring in adjacent stronger stations if you move it too far either way.

I’m surely not able to pin down the science involved in exactly how these things work, but perhaps somebody can chime in on this. I’m wondering if analog radio tuning in particular is better suited to the use of these tunable passive antennas, as opposed to PLL and DSP radios?

If you buy one of these be prepared to wait. At least mine took weeks to get here from Greece. And don’t expect miracles. But it seems rather well constructed, and will probably work with some radios. The seller has a 100% rating on eBay and has all sorts of interesting antennas for sale. I’m glad to see people succeeding in that business.

Many thanks, Prof, for sharing your fine review of the RFA200! Thanks for also mentioning the Tecsun R9012–I purchased one a couple years ago with the intention of reviewing it, then gave it to teenager who expressed interest in shortwave. I don’t think I actually put it on the air myself. I do enjoy simple old school analog radio–especially when making band scans. 

Click here to view the RFA200 antenna on eBay.

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Recommending the Tecsun PL-880 over the Sangean ATS-909X

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Many thanks to SWLing Post contributor, Direwolf131, who recently commented on one of the Sangean ATS-909X reviews in the Post archives.

Direwolf131 writes:

I’m a few years after Steve’s comments but I will have a go at it, at least anecdotally speaking. I’ve owned a half dozen Sangean ATS-909’s, which includes two of the 909X’s, and one super-909 from radiolabs. The 909X is the finest looking portable I have ever seen or lain hands upon, and that includes several Sony’s that I still think of as neat looking, I had the white cabinet 909X first and then the much more striking (to my eyes) black cabinet 909X after returning the first one due to rock hard buttons.

They are both extremely attractive, and exceptionally well made, especially by today’s cheap Chinese standards. I must confess that I also still find the original 909’s almost equally neat looking, though not quite sporting the same robustness of build.

The 909x’s sound wonderful on MW & FM, and its a decent performer reaching out to fairly distant FM stations. Unfortunately that is largely the best of the radio, its performance on MW & SW is best described as pathetic, and not just due to being deaf, it has a lot of noise, even when attached to the superb RF systems tuned EMF antenna. The older 909 is also to my experience substantially better then the 909X when matched up to a serious outboard antenna, such as the above EMF, I found this difference especially surprising, its not even close.

The PL-880 from Tecsun blows it away on SW and MW sensitivity, while also offering the superb advantage of genuinely ECSS tuning anything on MW & SW, you cannot decently receive any MW or SW signal via ECSS with the 909X as its SSB can only be fine tuned to 40 Hz, which is terribly disappointing, you can zero beat the little Tecsun easily. serious ECSS capability is to my mind a much more attractive option then a sync circuit, and unfortunately with the beautiful little Sangean 909X you get neither.

I do hope anyone who happens upon this pays attention, because for the money the PL-880 is far and away the better performer, in fact my little 1103 from Degen/Kaito out performs the 909X, as does my Grundig Yacht Boy-400, and my Sangean ATS-803A. Its my great hope that Sangean seriously upgrades these deficiencies in the otherwise gorgeous 909X, its circuitry is noisier than the old 909 and its not nearly not as sterling a performer hooked up to household current and a decent outboard antenna as the old 909, its 40 hz tuning SSB once a great reason to buy a 909, is no longer competitive, especially against the superb PL-880 which again is capable of excellent ECSS even by Icom R75 standards, Sangean would do well to drastically improve the SSB performance of the 909X.

I hope this helps, I liked the original review up top, but again its several years old, and the ATS-909X is now known to be clearly outclassed by the more affordable Tecsun, actually by the PL-660 to boot, I really hope Sangean addresses the issues, its such a beautiful receiver, you just want it to be as good as it looks, unfortunately it’s not!

Thank you for sharing your evaluation and comments!

The Sangean ATS-909X is an interesting radio indeed. Almost everyone loves the design, audio and overall quality of the 909X.  Yet performance reviews are somewhat polarizing: some 909X owners claim the 909X has strong performance characteristics on shortwave, while others believe it’s almost deaf. Your findings coincide with mine from the Mega Review where I pitted the ATS-909X against the Tecsun PL-880, PL-660 and Sony ICF-SW7600GR. In that review, where I relied on a whip antenna, the 909X was noticeably less sensitive than the other three competitors. Based on the premium one pays for the 909X, I was surprised.

I have learned over the years, however, that the 909X can handle larger outdoor antennas and doesn’t easily overload. Additionally, the 909X requires a fresh set of batteries for optimal performance/sensitivity. Some users have even modified the radio with a 4:1 impedance transformer–click here to read a post/comments about this mod.

I would love to see Sangean produce an updated/upgraded version of the 909X, but at this point I’m not exactly holding my breath. I’ve heard that they’re slowly pulling out of the market. Hope I’m proven wrong because I’d love to see a new shortwave set from Sangean.

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A detailed review of the XHDATA D-808 and comparison with the Tecsun PL-660

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Many thanks to SWLing Post contributor, 13dka, for the following guest post:

A review of the XHDATA D-808

by 13dka

After all the recent buzz about the new XHDATA D-808 I had to get one. I got mine 3 weeks ago and I couldn’t help comparing it a lot with my PL-660. The PL-660 lends itself to such a comparison: it turned out to be the most sensitive shortwave portable with SSB in some comparison tests, so it became some kind of benchmark radio for this class of receivers and it has the same coverage as the D-808. Here are my findings, let’s start with the important stuff:

Performance

13dka’s “happy place” on the German North Sea shore.

I always try new receivers at my favourite listening post at the (German) North Sea shore, many of you know how beneficial such a location is for DXing. My favorite spot there is far away from any houses, power lines or other interference sources on the land side, so besides some sheep-made noise the man-made noise is as low as it gets, measured less than -130dBm (which is the receiver noise) on a 1/2 lambda dipole above 10 MHz.

At the same time the close proximity to the water results in somewhat boosted signals, so I can assess both reception quality at the lowest sensitivity threshold and behavior with strong signals. Sometimes it lets me find quirks that would go unnoticed anywhere else.

Here are my findings with the D-808:

Sensitivity

Longwave

Since users in the US have little ways to test that, let me assure you that all rumors you may have heard about a deaf longwave are perfectly true: the European LW broadcast band is pretty much not existing on the D-808. All those reports (e.g. many to find in Amazon reviews) indicate that really all D-808 are affected. The PL-660 is known to be very deaf on LW as well but it picks up a few stations in the evening, only some of them leave a faint clue on the D-808 and it can’t pick up BBC 4 on 198kHz even at night.

The signal meter indicates that it gains some sensitivity only above 300kHz, but from there it quickly starts to beat the PL-660 – during the day I can hear all of the local NDBs, something I can’t say about the PL-660.

AM broadcast band

This continues throughout the AM broadcast range – best tested during the day and on early evenings, the D-808 lets me ID weak stations that are just not there (yet) on the PL-660. Being noticeably better than the Tecsun, I then compared it to my old Grundig Satellit 400 (which has an average sensitivity on MW) and the D-808 matches its performance perfectly. So perhaps it’s not exactly a MW DX machine with just its internal loopstick but it performs well enough to make the band enjoyable.

Trying that at night and indoors shows why the right time and a low-noise location (or alternatively proper test equipment) are so important for such comparisons: any weak station sticking out of the distant and local QRM there is not as weak as it sounds anymore, both QRM and wanted signal are now well above the sensitivity thresholds of both radios and so SNR is defined only by the QRM, not the receiver. That means both radios falsely appear to have exactly the same sensitivity.

Shortwave

Notwithstanding some duds, the PL-660 is known to be a little sensitivity monster on shortwave. When I don’t feel like putting up wires etc. for my SDR, I just take the Tecsun to the beach and through the years I own it, I’ve logged plenty of true DX (JA, VK/ZL or WWVH on a regular basis) with it there, just using the telescopic whip.

Only below 3 MHz it’s not all that great on the whip, and that’s where the D-808 beats it – listening to top band (160m) hams works surprisingly well for a 25 inch whip. Between 3 and 30MHz the D-808’s sensitivity appears to be almost on par with the PL-660, the PL-660 often wins in terms of intelligibility at the “minimum discernible signal” (MDS) threshold. For example, on a day with bad conditions Gander Radio on 6604kHz USB had a barely audible signal on both radios. But I could occasionally decipher some words on the Tecsun that didn’t make it through the noise on the D-808. These photo finish victories for the PL-660 can be observed across most bands, but it needs ridiculously weak signals to spot the difference.

This difference is partly due to the fact that the D-808 seems to be a tad more noisy and partly owed to the better speaker of the PL-660. But the PL-660 also sports the often frowned upon “soft muting” feature, thus creating an impression (or should I say illusion?) of a pretty quiet receiver. I find it hard to tell whether the D-808 is really noisier than the PL-660, or just lacking this permanent noise reduction. I think this feature potentially even increases intelligibility on SSB a tiny bit, but on AM it’s just disturbing and makes the Tecsun lose its sensitivity advantage. Bottom line is that the D-808 is at least very close to the PL-660 in terms of sensitivity on shortwave and I find that quite remarkable.

FM

Both receivers are pretty identical in FM performance on their whip antennas. Sensitivity is good enough to pick up high-power stations more than 100km away in times without any elevated conditions. Both receivers don’t need much signal to make a station intelligible, so when conditions improve a tiny bit (“marginal” indications on the Hepburn Index map) the band already gets populated accordingly. One difference is the coverage: the PL-660 can be switched to cover the Japanese FM band (76-108MHz) only, the D-808 covers the old OIRT band (64-108MHz) on top. What makes the D-808 the winner is its RDS/RDBS capability and the size, it certainly has the sensitivity needed for some ad-hoc FM-DX when you find yourself bored on a hill or in sudden tropo conditions.

By the way: RDS gets decoded sufficiently fast and starts to show on signals with an SNR of at least 12dB (see the bit about the RSSI/SNR meter below). If the station transmits date information it will set the clock automatically, but when you go on a hunt for stations it may receive some garbage data that resets the clock to a wrong time. It may be best to turn on the automatic only occasionally to set the clock, then turning it off again.

Air Band

The D-808 is at least as sensitive as my Alinco DJ-X11 scanner and skunks the rather deaf Tecsun in this band. Unlike the PL-660 and most other small receivers covering that band it has a squelch, which is by the way active on all bands.

What it lacks is the new 8.33 kHz channel spacing, the “Fast” tuning step is still 25 kHz (“Slow” is 1 kHz) and the scan searches the band in 25 kHz steps as well, so I have to tune in the new channels manually. But while it lacks the new spacing, it absolutely has the selectivity for it – the AM filters are all available on the air band as well and even the widest one is still good enough to separate adjacent channels sufficiently. My 6 times more pricey Alinco has the new 8.33 kHz channels but it can’t separate them at all.

The D-808 is a great air band receiver!

Selectivity

The PL-660 has 2 (I think unspecified) ceramic IF filters for SW, which are doing a good job serving 90% of all typical purposes for such a radio. The D-808 on the other hand utlizes the DSP for IF filtering and offers whopping 11 different bandwidths (6 on AM and 6 for SSB), this is even more than the PL-880! This sold the D-808 to me the most, for example I like to improve my very poor CW listening skills every so often, and always having an even narrower filter up the sleeve can save otherwise hopeless DX reception in the ham and broadcast bands. But are they any good?

SSB: 500 Hz, 1 kHz, 1,2 kHz, 2,2 kHz, 3 kHz, 4 kHz

The 500 Hz “CW filter” seems to have a rather slow cutoff, unlike a true 500 Hz CW-filter it leaves voice communication almost intelligible. Still beats trying to hear CW through a regular SSB filter though! The 1 kHz filter seems to be the only one with an offset lower skirt (=less bassy sound), which can be useful in some cases. I’m not quite getting the purpose of the 1.2 kHz filter, I think I’d prefer a 1.8 kHz filter for a step between 1 and 2.2 kHz. The 1.2 through 4 kHz filters have the steeper cutoff you’d expect from DSP filtering and serve their purpose pretty well. In the “Gander Radio” example above, the narrow filter on the PL-660 couldn’t keep 4XZ’s CW signal on 6607kHz in check, while the D-808’s 2.2kHz filter eliminated the CW signal completely. I’d still take the bandwidth figures with a grain of salt though.

AM: 1 kHz, 1,8 kHz, 2 kHz, 2,5 kHz, 3 kHz, 4 kHz, 6 kHz

Oddly, the published bandwidth for the AM filters seem to be “audio bandwidth” (or “per sideband”) figures rather than IF-bandwidths, so they equate to classic IF filters with 2/3,6/4/5/6/8 and 12 kHz bandwidth. The only overlap is 4 kHz, hence I say it’s 11 different bandwidths, not 10. I think these AM bandwidths should cover all requirements that might come up, on top of those you can try ECSS reception with the SSB filters.

SSB Reception

On pretty much all of the tiny shortwave portables, SSB reception comes with some tradeoffs and the D-808 is no exception. When the PL-880 hit the market a few years ago, the amount of filters for SSB offered by the Si4735 DSP raised my hopes for improved SSB, but unfortunately the D-808 has the same problem that kept me from buying the PL-880 back then, and some on top:

AGC distortion

Like the PL-880 (at least some of them), the D-808’s AGC has a way too slow attack rate, the first portion of any strong SSB/CW signal is distorted before the AGC levels back, and it increases gain fast enough that even short talking (or keying) pauses make the next syllable distorted again. This seems to plague most (if not all) Si4735-equipped radios, so that might be actually a bug of the DSP.

Tuning

The chuffing noise is making tuning through the band quite bad in SSB mode, it’s even worse than the early digital “keypad”-style radios in the 1980s: every tuning step is causing first a short muting of the signal, then audio comes back with a loud “chuff” from the AGC kicking in with full gain – tuning sounds like a model railway steam engine sound chip gone mad. Luckily, fine tuning with the thumb wheel doesn’t have this issue.

Filter dropouts

Another issue is an occasional effect that sounds and feels like the filter drops out when you tune through the band. The chuffing sounds different and the background noise sounds wider with more hiss, then after a while (this can take several seconds) the filter pops back in with the regular puff from the AGC.

Slow mode switching

When switching to SSB a “loading bar” shows up first, the entire process between hitting the “SSB” button and getting reception again takes 5 seconds. Actually, these radios basically consist of a “radio-on-a-chip” and a microcontroller so it really might be a loading bar we see there. This controller seems to be not exactly fast in the D-808 anyway, so even using the tuning knob comes with occasional hesitations – I advance the main tuning encoder one indention and the frequency changes only 1-2 seconds later. Changing bands is not exactly fast either but at least toggling between USB and LSB works instantaneously.

In comparison, the PL-660 has none of these issues – tuning is smooth and fast, and the AGC is less borked. So tuning the D-808 isn’t elegant and it doesn’t sound exactly beautiful on SSB. On the other hand it has great frequency stability, great selectivity and sensitivity and I can hear what I want to hear anyway. At 1/3 of the price for a PL-880 and pocket-friendly 2/3 of its size I decided to avoid overrating the quirks.

AM Reception

… is fortunately less odd. The chuffing gets replaced by less annoying muting when tuning in AM mode, the ability to quickly scan a band with the main tuning knob seems to be less hindered by that. The PL-660 has a mediocre sync detector and the D-808 has not, but it can score with easier ECSS reception through its much less fiddly fine tuning in 10 Hz-steps (range +/- 990 Hz with the last digit omitted in the display) and the choice of filters is a clear advantage over the Tecsun’s 2 bandwidths in tricky DX situations. As mentioned above, the Tecsun is also losing its sensitivity advantage due to the soft muting on AM, so its remaining big plus is the more pleasant speaker sound.

Signal handling capabilities

As mentioned above, signals can increase quite a bit in very close proximity to the water. When conditions were good, I’ve witnessed occasional overloading even with just the whip antenna on the PL-660 there. But the Tecsun has a 3-position sensitivity switch that first turns off the input amplifier and then adds an attenuator, so it can manage these situations by turning off the preamp and it happily digests signals from full size dipoles, long wires and active antennas with the built-in attenuator in the signal path.

The D-808 has no such thing and that makes it at least as vulnerable to overloading from good conditions or big antennas as the PL-660 without attenuation. At the beach it exhibited very faint intermodulation even at propagation conditions that were just “not quite as crappy as the current record low” when the Tecsun did not. They were so soft that I think this can’t be heard when the noise level is a bit higher, still a bit strange. Intermodulation products seem to show up most prominently around 7MHz, 10MHz and in the 15m ham band first.

Other than that, it seems to abide <10m/30ft of wire just fine and it gets along with my ML-200 active loop, currently indoors with a rigid 80cm aluminum loop, unless the RRI transmitters populate 49 and/or 41m after midnight. That station occasionally hits the 9+60 mark on my SDR with a dipole and when they’re on, the D-808 has to be tuned far away from these bands or disconnected from the loop to stop the pumping, desensitizing and intermodulation products. Interestingly, strong signals often make the filter drop out (as described under “SSB reception”) as well. A theory could be that this happens when an off-band signal (and/or the AGC causing “clipping”) makes an AD-converter run out of bits.

That even regular good signals outside the filter passband can trigger unwanted AGC action might be more or less common with most of those DSP radios. The massive worldwide contest activity on March 24/25 was a nice opportunity to test that. Even though I fled to the less crowded upper region of the 20m-band and it was an hour after sunset so the band was closing, I noticed the AGC was pumping a lot while listening to a contester with a moderate signal. It could be the the ceramic filters (which are said to have better out-of-band rejection) or just the way my Tecsun’s AGC works (or malfunctions) differently, however this effect is much less pronounced on the PL-660.

Frequency stability, accuracy, birdies, quirks

Both receivers are generally very stable and don’t exhibit a noticeable warm-up drift. Just to see what happens, I took the D-808 from a very warm apartment into cold (-5°C/28F) and stormy weather outside. The internal (and very slow changing) thermometer of the D-808 indicated an internal temperature drop of 12°C within 10 minutes and if there was a drift at all, it drifted less than 10Hz.

Comparing the BFO frequency accuracy (using RWM on 4996 and 9996 kHz) brought up some slight offsets across the coverage range, with different curves for LSB and USB:

4996: USB=-160 Hz, LSB=+110 Hz
9996: USB=-190 Hz, LSB=-300 Hz

So particularly on LSB, the offset on my D-808 varies quite a bit over the entire coverage range but I think this is within the allowable tolerance for such a radio. The PL-660 has slightly better results but it also has a center-indented fine-tuning knob making small corrections quite difficult. In AM mode they are both spot on.

So far I couldn’t find birdies anywhere on the D-808. The PL-660 is pretty clean on shortwave too, but it has hefty birdies around 100, 200 and 970kHz, despite the efforts Tecsun has put into shielding and clean PCB design.

SWLing Post reader Mike reported a loud “pop” when changing bands. I can replicate that but it’s not that loud here. I’m getting a much louder pop (independent from the volume setting like Mike’s pop) when using the band scan function though. If I’m tuned to a station and another station (strong enough to stop the scan) is quite close (10-15 kHz) to the station where the scan was started, a loud pop will be heard when the scan stops at the other station.

Operation/Ergonomics

Both receivers have some “thin plastic” feel to me, but while my PL-660 has some slightly rattly and wiggly buttons and knobs rubbing against the casing, the D-808 has none of those and feels a tad more solid. The tuning knob and the fine-tuning thumbwheel have quite strong detents, so they are not very prone to unintentional detuning. The D-808 lacks the weight and the tiny rubber feet that keep the Tecsun fixed on the table.

Control

I’ve seen quite a few complaints/misunderstandings about the D-808’s operation and I think this is due to the fact that there is a fundamental difference between e.g. many Tecsuns and the D-808 in terms of keypad usage: the PL-660 is prioritizing direct frequency input and the D-808 makes memory operation easier. It couldn’t be any easier indeed – depressing a number button on the keypad for more than 3s stores a frequency, hitting it shortly loads that frequency. “Page” button, then number key loads the memory pages 0-9 on each band (so each band has 100 memories). Like the PL-660, the memories store frequencies only, not the mode and also not the bandwidth (despite the manual claims they do). Also differing from the manual, the selected bandwidth stays put per mode and doesn’t reset to a default setting.

Direct frequency input needs to be initated with the “Freq” button though, and in some cases (shortwave frequency <10,000kHz) you need to hit it again to enter the frequency. The D-808 has up/down buttons in addition to the main tuning knob, they are stepping through the bands in the “Fast” step width so you can pretty much always leave the tuning knob on “Slow” . Pressing these buttons longer than 3s starts the band scan. Holding each of the left side band buttons starts the “ATS” scan-and-save-to-memory automatic.

The D-808 shares the “power off” settings scheme with the Tecsuns – some functions like LW on/off, the FM band coverage and so on are set when the radio is off. These functions are labeled in orange above the corresponding buttons and I share the criticism about the color scheme, which is really hard to read in less than optimum lighting conditions. Also, some of the labels are actually “power on” functions marked in the same color, like the “METER” function on the SW band button (hit the SW button repeatedly to step through the broadcast bands) or the USB/LSB switching and key lock functions activated with the “Info” button.

Display/Backlight

Despite the size difference, readability of the display is fine on both receivers. Backlight control is fundamentally different tho: You can turn off the automatic backlight on the PL-660 but you can’t turn it permanently on, the D-808’s light button toggles between “permanently on” and off but you can’t turn off the automatic. The backlight is objectionably bright on the D-808, the upside is that it serves well as a reading light and the light reflected off your hand can illuminate the buttons sufficiently to substitute the missing button lighting.

Some random things I like:

RSSI/SNR meter

Like the PL-880 and some other Tecsun radios, it has a somewhat odd “dB over 1 microvolt”-like signal indicator. It lacks the negative figures needed to properly represent the ~S0-S3 range, it just goes from ’00’ to ’99’ and it’s strangely labeled as “dBu” but technicalities aside, it is a signal indication in 100 steps which is certainly more useful than a 5 bar indicator. According to reports, other receivers with this RSSI don’t seem to use the entire display range and end at ’75’ or less. However I can see the D-808 showing ’99’ when I’m at our airstrip and the tower transmits.

The second pair of digits is a crude calculation of receiver (not audio!) SNR, which can be useful in conjunction with the signal strength meter, e.g. for adjusting or comparing antennas and so on, and it works best with AM and FM signals.

Battery Endurance

“18650”-batteries have a very high energy density at a very low weight, and in the D-808 they meet a radio with a very moderate power consumption. As a result, the provided 2,000mAh battery powered the radio continuously for remarkable 32 hours, 14 of them with the display light on! For comparison, the heavier (and more expensive) 2,500mAh Ni-MH batteries in my PL-660 last for 24 hours only.

It seems the quality of the packaged battery is all over the place though, one user reports “have to charge every day”, another one “28 hours”. If in doubt, a Panasonic 3,400mAh battery (this is the current technical limit for 18650s, don’t fall for fake “10,000mAh” offers seen on Amazon and eBay!) should last for a long weekend even if you’re listening all day. Make sure you buy the “protected” type, the other flavor (used e.g. in electric cigarettes) doesn’t work. If you happen to be a high-performance flashlight fan, you may already have a bunch of batteries to keep the D-808 going forever.

The manual claims that the D-808 can’t be charged when it’s on but I found that’s not quite true–it sure takes much more time but I could top off a slightly discharged battery just fine.

Charging it from a USB charger or laptop USB port introduces some additional noise on AM/SW of course, trying a cheap power bank worked out much better in this regard.

A true “Walkman” for SWLs

The PL-660 fits in some big pockets only and weighs more than a pound. The D-808 has only 2/3 of the Tecsun’s size and I can stuff it conveniently into all of my jacket’s side pockets (tuning knob ahead) so the whip can stick out easily without getting into my way at all. It has at most half the weight of the Tecsun, it weighs less than my smartphone!

This is making an old dream come true for me – a full-featured “communication receiver” (well, almost) that’s “wearable”, one that allows me to enjoy hands-free and hassle-free full shortwave reception on all bands without compromises (particularly in sensitivity) when I do the boring walks the doctor prescribed!

Outsides where the noises of the digital world are gone, the D-808 presents all bands almost as filled as my dipole at home and so there’s always an interesting QSO or some overseas radio program to enjoy. To give you an idea on what I mean by “no compromises”: my companion on today’s walk was NY2PO from upstate NY (3,728mi/6,000km away) on 40m, constantly coming in with a signal allowing for convenient listening, despite the bad conditions (SFI=68 A=10).

I think this may be the first time a radio with so many features and such a high sensitivity comes in such a small package – all handheld scanners with SW and SSB were an expensive atrocity on shortwave, the late ICF-7600 was slightly bigger, less sensitive and SSB was not its strength. The only radio with even more features and similar dimensions would be the “Reuter Pocket” SDR but that might be less sensitive on a whip, it lacks the air band, it has a 1-digit battery runtime and a 4-digit price tag. The only other affordable radio that could fit that bill would be the even smaller Tecsun PL-365 SSB, but it lacks an SSB filter, it has no RDS and no air band and I’d be curious if it can match the sensitivity of the XHDATA.

Verdict

The D-808 can score in 3 bands (Air, FM (due to RDS) and AM) with its sensitivity, the PL-660 only on LW (due to the fact it actually receives something there) and by a narrow margin on shortwave. The Tecsun’s (perceived) lower noise floor, better speaker sound, better tuning and built-in attenuator is countered by a much wider choice of filters, better fine tuning control, better portability and the better battery endurance of the D-808. The latter also has a number of less important features the former lacks, on the other hand the Tecsun lacks the many quirks of the D-808. It’s up to you to weigh the advantages of each to find your personal favorite, the D-808 struggled a bit to become mine but at the end I couldn’t help enjoying this little radio a lot.

There is much room for improvement though – for example the slightly borked control of the DSP, the chuffing/tuning and AGC issues on SSB let the D-808 miss the title “most stunning cheap little radio ever” by a hair.

For me, the unique combination of size, sensitivity and selectivity is making up for the shortcomings, it certainly remains a very interesting radio and I can’t remember carrying one around that much, ever.

What a brilliant, detailed assessment of the D-808! Thank you so much for sharing this! I’m absolutely jealous of your North Sea listening location–looks to be idyllic! 

Check out the XHDATA D-808 on Amazon.co.uk (affiliate link) and AliExpress.

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Video: How to calibrate the Tecsun PL-660 frequency offset

34 Replies

Many thanks to SWLing Post contributor, Mike Mander, who writes:

I’ve recently really been enjoying swling.com. Thanks for having such a great resource online with shortwave radio and hardware reviews, tips and more! I started listening to shortwave on an old Philips portable receiver back in the late 70’s as a teenager. Recently, after decades of not listening to shortwave, I decided to buy an Eton ‘Grundig Edition’ Satellit radio and in no time at all, I had also acquired a C.Crane Skywave SSB and now, within the last week, a Tecsun PL-660.

[…]I thought I’d record a video showing how one can calibrate AM, FM, SW wide-bandwidth as well as SW narrow-bandwidth independently, and how to reset those calibrations back to factory default. I have not heard it mentioned anywhere that one can calibrate both wide and narrow bandwidth SW modes independently.

Online, I have read about many people being disappointed in their PL-660’s wide-bandwidth frequency calibration, where often being on-station results in the frequency being up to 5 kHz too low, and it seems many simply return their radios as defective, not realizing how easy it is to recalibrate. This is the first “instructional” video of this sort that I’ve ever posted online, so you’ll have to pardon if I am perhaps not explaining things clearly enough:

Click here to view on YouTube.

Excellent video, Mike! You’ve done a fine job making the explanation clear and easy to follow. Thank you for sharing!

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Comparing the XHDATA D-808, Digitech AR-1780 and Tecun PL-660 on shortwave

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On Friday, I managed to set aside an hour to finally do a video comparison of the Digitech AR-1780 and the new XHDATA D-808.

I placed a table in my driveway, far away from any source of RFI, and set up the radios in identical configurations: same orientation, antennas fully-extended, same AM bandwidth (4.0 kHz), same audio levels, etc. For good measure, I also included the venerable Tecsun PL-660 in the mix.

This was still daytime listening, so all of the stations were from 31 meters and up.

Apologies in advance: somehow the cord from my monitoring headphones is in the shot on some of these videos! I’m still getting used to the new Zoom Q2n video camera:

WRMI 9,455 kHz

Click here to view on YouTube.

WWV 15 MHz

Click here to view on YouTube.

Deutsche Welle 15,200 kHz

Click here to view on YouTube.

Afia Darfur 9,825 kHz

Click here to view on YouTube.

I should add that QSB was slow and deep on Friday. Twice I had to re-shoot videos because the station simply faded into oblivion.

I plan to do a few more comparisons with the XHDATA D-808 and Digitech AR-1780 soon as I’m very curious how SSB reception may differ.

Please comment with your observations. Which radio did you prefer? I’ll hold my comments for now.

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Tecsun PL-880 hidden feature/hack: 1 kHz bandwidth on shortwave

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[Note: This procedure was updated and simplified by Guillermo on 22 December 2017]

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

I own the PL-880 and just discovered a new feature : a 1.0 kHz bandwidth mode on shortwave (SW only not in MW).

The procedure to get it is as follows:

  1. Turn on the radio and tune any frecuency on SW . There is no need to connect or disconnect an external antenna and turn on or off the radio during this procedure.
  2. Be sure that on SW the 4 button feature(press 4 for about 2 seconds) is ON and 9 button feature(press 9 for about 2 seconds) indicates a value of 13 or more and not less than 10.
  3. Then turn OFF 4 button feature and then ON again . Press BW button and see the 1.0khz new BW on the screen. Now you can use it permanently on SW and ALSO on MW , UNTIL you press BW button again .

Well, I hope you understand this description–if not please let me know, and tell me if it works on your unit, or it is just works on mine.

Thank you, Guillermo! I see where this is somewhat of a fragile adjustment in that a number of actions could change the bandwidth back to a previous setting, but nonetheless is quite a fascinating hack/hidden feature! Thank you and I’ll add this to our list of PL-880 hidden features.

Post readers: please comment if you can successfully enable the 1.0 kHz bandwidth on your unit.  Please comment with your radio’s manufacture or purchase date if possible.

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