Category Archives: Reviews

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

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.

The Muzen OTR: initial look and impressions

A lot of SWLing Post readers have been contacting me lately noting that they’ve received their Muzen OTR/Radio Caroline FM radio and Bluetooth speaker.

Muzen started shipping the new OTR to their backers this week.

I received my OTR yesterday and am completely in love with this little gem. Without a doubt, it’s one of the highest quality pieces of consumer technology I’ve purchased in years.

Yesterday, by request, I made an unboxing video–I plan to post it later today when I have a good broadband connection.

I’ll also follow up with a proper product review, but I can say now that the Muzen OTR has amazing audio fidelity for such a tiny little unit–it’s room-filling. The FM tuner works well (although the dial is tiny). The solid wood chassis is beautiful, refined and sturdy.

The OTR shipped with the highest quality leather carrying case I’ve ever received with a product. It smacks of 1960s quality (or even better!).

The OTR is a salute to the famous Radio Caroline–as a nice added touch, they even include a tribute in the form of a QSL card.

The Muzen OTR package also includes an audio cable, USB cable, and FM antenna.

What a pleasure to receive such a quality piece of kit! Look for my review soon.

Post readers: Did you back the Muzen OTR as well? Received your unit yet? Please comment!

An initial look at the C. Crane CCRadio-EP Pro

Earlier this week, I took delivery of the latest radio from C. Crane: the CCRadio-EP Pro. C. Crane sent me an early production model for evaluation.

Since posting an announcement last November, several SWLing Post readers have contacted me and asked if I would take a look at this next iteration of the venerable CCRadio-EP.

Yesterday, I started a proper evaluation of the EP Pro by taking it to a park where I compared it with my trusty Tecsun PL-660 on AM/mediumwave.

First impressions are favorable in terms of sensitivity, stability and audio, but with a number of caveats.

The Silicon Labs SI4734 diagram

The EP Pro is not a true analog set like its predecessor–it’s based on the Silicon LabsSI4734 DSP chip.

In other words, much like the Degen DE321, the Degen DE32, the Tecsun R-2010D, the Kchibo KK9803 and the ShouYu SY-X5 (which I review in a shoot-out here), the CC-Radio EP Pro is a mechanically-tuned DSP receiver.

On the plus side, the new EP Pro will not drift like its analog ancestor (a common complaint from EP owners).

But truth be told, I’m not the biggest fan of mechanically-tuned DSP radios. Why? For one thing, it’s nearly impossible to eliminate muting between 10 kHz frequency steps on the AM band. Note here that the EP Pro is fixed at 10 kHz steps, though C. Crane tell me a future production run will have a 9/10 kHz step toggle.

Additionally, the EP Pro produces false peaks/images on either side of a strong AM or FM signal. In fact, C. Crane includes the following informational insert with the EP Pro:

This is going to be a quirky radio.

The tuning mechanism is…well…unusual…and takes some getting used to. I’ve also discovered that the top half of the AM dial is inaccurate. Here’s the EP Pro centered on WTZQ at 1600 kHz:

I estimate that the slide rule dial is off by about 40-50 kHz at the top end of the band. It’s much more accurate below 1,200 kHz, however. I plan to hook the EP Pro up to a signal generator and note the results in my forthcoming review.

Speaking of an EP Pro review, I plan to publish it within the next two weeks, so stay tuned!

Follow CCRadio-EP Pro posts by bookmarking this tag: CCRadio-EP Pro

Click here to check out the CCRadio-EP Pro on C. Crane’s website.

Dave’s review of the AOR AR-DV1 Digital Voice Receiver

Many thanks to SWLing Post contributor, Dave Zantow (N9EWO), who has recently posted his review of the AOR AR-DV1 digital voice receiver.

As with many of Dave’s reviews, this evaluation takes a close look at HF and mediumwave performance which isn’t the AR-DV1’s strong suit. Dave notes:

“[Though] not what the receiver was designed for, RF performance on MW / HF bands (and the terrible audio quality) are mediocre at best.”

Click here to read Dave’s review.

Thanks, Dave! Your review reflects comments I’ve received from some Post readers who’ve purchased the AR-DV1 as well. Many were particularly upset with the audio quality. Of course, the AR-DV1 is marketed as a digital voice receiver, thus audio likely favors “narrow” voice audio.

Colin’s review of the CC Skywave SSB

Many thanks to SWLing Post contributor Colin Newell of DXer.ca who shares part one of his review of the CC Skywave SSB.

Colin’s review is nothing short of glowing and he obviously has a first production unit that isn’t plagued with the DSP noises five of my review units had.

As I stated in my review, the Skywave SSB is an impressive little receiver when DSP noises and birdies aren’t an issue. My Beta unit is a lot of fun to put on the air and has become my go-to “Swiss Army Knife” travel radio.

I will be testing an early second production unit of the CC Skywave SSB later this year and will post my evaluation here on the Post.

Click here to read part one of Colin’s review.

 

A review of the Tivdio HR-11S self-powered shortwave radio

A few months ago, the radio manufacturer Tivdio contacted me to see if I would be interested in evaluating their new Tivdio HR-11S self-powered emergency radio. I receive requests like this frequently, and often pass on the opportunity since I generally don’t have the time to evaluate the overwhelming number of inexpensive DSP radios that have hit the market in the past few years.

But this time, I seriously considered it.  There were two reasons I was interested in the HR-11S:

  1. I purchased a Tivdio V-117 last year, and have been pretty pleased with it; indeed, I’m overdue a review on this unit. We’ve also posted several positive reviews of the Tivdio V-115.
  2. At our non-profit ETOW, we’re always looking for reliable self-powered radios with shortwave for use in areas of the world where radio remains the primary news source.

Thus this radio is a rather rare breed.  Tivdio dispatched the radio very quickly, but my work with the Radio Spectrum Archive and several other reviews already in the pipeline took priority.

I’ve had the HR-11S in service for several months, and have now explored every feature to some degree. What follows is my summary and review notes.

Green and Red radios are different models

First things first: note that I’m reviewing the Green HR-11S. Tivdio also makes a Red version which is actually a different model number: the HR-11W.

The main difference between these models, as I understand it, is the green HR-11S is a shortwave version, and the red HR-11W is a NOAA weather radio version.

Both are useful; why not combine the two roles in one unit?  I’m not surprised this radio can’t include both shortwave and NOAA weather radio. Through Ears To Our World, I’ve worked with self-powered DSP radios for many years, and know that a limitation of the DSP chip is that it can be set to feature either shortwave or weather radio, but not both, simultaneously, if both AM and FM are included.

Form factor

The HR-11S has a built-in solar panel.

The HR-11S adopts the standard “flashlight” form factor found in so many other self-powered radios. I think the flashlight functionality is a useful feature and results in a handy form factor.  It’s compact, lightweight, and seems relatively sturdy, so is suitable for camping, travel, and off-grid utility.

Flashlight/Siren switch

A small switch on top toggles between four positions. The first two positions are off/on for the main white LED. Though the flashlight aperture is relatively small, the white LED provides enough luminosity to light your immediate path at night, and certainly more than enough to read by.

The third switch position engages a flashing red LED. The red LED is not terribly bright and I’m not sure how helpful this would be in an emergency situation.

The red LED is rather dim and can only flash.

I would much rather have the red LED maintain a steady beam which would be great for amateur astronomers, campers, or anyone else wishing to preserve their night vision.

The fourth position engages a LOUD siren. More than once when attempting to turn on the flashlight in the dark, I’ve accidentally engaged this pain-inducing feature. The switch is small, thus it’s very easy to engage the siren. In a quiet campground, this might annoy your neighbors––not to mention you, yourself.  Of course, in an emergency situation, a loud siren could come in handy. I just wish its switch wasn’t combined with the flashlight switch.

The display HR-11S display is backlit and easy to read.

The HR-11S sports a keypad that allows direct frequency input––a very good thing, considering there is no tuning knob.

To band scan, you must use the #7 and #8 key on the keypad to increase and decrease frequency in predetermined steps. And, yes, the radio mutes between frequency changes.

You can also press and hold the #7 or #8 buttons to engage an auto-tune feature that finds the next strong signal.

The HR-11S’ rechargeable battery pack.

To input a frequency directly, simply press the enter button, key in the frequency, then press the enter button once more to engage that frequency. Very simple.

The volume up/down buttons are #1 and #2 on the keypad.

The keypad is not backlit and the layout for volume control, tuning, mode switching, etc., is a bit confusing; it doesn’t match any other radio I’ve ever used.  Of course, with time you’ll master the keypad functions, but the design could be made more user-friendly.

Performance: setting expectations

SWLing Post community members know that I tend to review what I call “enthusiast grade” radios: receivers that perform well enough to attract the attention of DXers and dedicated listeners.

Self-powered radios, with few exceptions, rarely impress me in terms of performance. Indeed, some of the best that have been on the market have been analog units (I’m particularly fond of the Grundig FR200).

The Tivdio HR-11S is no exception––don’t expect to snag elusive DX with this unit. It’s not going to happen.

FM

The HR-11S is a capable FM receiver. Performance is on par with most average FM radios: you’ll easily receive all of your local broadcasters, but distant stations may require holding the unit in your hand, careful positioning, or adding an extra bit of wire to the antenna.

The FM audio is quite good via the HR-11S’s built-in speaker.

AM

The mediumwave, or AM broadcast band, is the HR-11S’ weakest suit. AM is plagued with internally-generated noises–especially in the lower part of the band–thus you’ll only be able to clearly receive local AM broadcasters that rise well above the noise floor. Thus I cannot recommend this radio for AM reception.

Shortwave

Shortwave reception is on par with other DSP self-powered radios I’ve tested. As I write this section of the review, I’m listening to China Radio International on 9,570 kHz in my office without even having the telescopic whip antenna extended. (CRI is a blowtorch station, however).

I find that the HR-11S can receive most strong broadcasters and even weaker stations, though the AGC is not ideal when fading is present.

If you’re seeking a self-powered radio with shortwave, the HR-11S is somewhat useful in this regard and is worth consideration.

Keep in mind, though, that an inexpensive dedicated ultralight shortwave radio like the Tecsun PL-310ET will perform circles around this unit.

Bluetooth

One feature I’ve found incredibly useful is the Bluetooth functionality.  With Bluetooth mode engaged, you can connect the HR-11S to pretty much any mobile device and use it as a wireless portable external speaker. Since the speaker has decent audio fidelity for the size, and can be powered by battery, it’s a brilliant feature and will make watching videos on your smartphone, for example, that much better.

One negative? At least in my unit, I can hear some internally-generated noises in Bluetooth mode. This is especially noticeable at lower volume levels.

Recording

In full disclosure, I haven’t tested the recording functionality extensively. Built-in radio recording is an interesting feature, but one I would rarely use in a self-powered radio. I did make a handful of test recordings, however, and like many other DSP radios with a recording function, the HR-11S injects noise in the recordings.

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 my initial impressions and observations. Here’s the Tivdio HR-11S pro/con list, from the first moments I turned it on to the present:

Pros:

  • Keypad entry
  • Great audio for size
  • Replaceable battery (Note: after unboxing unit, you must place battery in battery compartment; it’s packed in the side box)
  • Siren  (see con)
  • Micro SD card for digital storage
  • USB can port audio from PC
  • Bluetooth––use as a portable wireless speaker for mobile devices (see con)
  • ATS (auto tune) function
  • Multiple power sources:
    • 850mAh rechargeable lithium battery
    • hand-crank dynamo generator
    • Mini solar panel
    • DC 5V input (standard micro USB)
  • Backlit informative display
  • Customer service: Tivdio representatives seem to respond quickly to customer emails and comments on Amazon.com.

Cons:

  • Tuning is cumbersome (no tuning knob)
  • Mutes between frequencies
  • Siren too easy to activate, resulting in accidental activation
  • AM broadcast band (MW) is plagued with internally-generated noises
  • Keypad configuration is not intuitive and difficult to memorize for use at night or low light settings
  • Hand strap is very difficult to insert (hint: use a thin loop of wire to help thread it)
  • At low volume, noises can be heard in Bluetooth mode
  • Noises heard in recording function

Conclusion

Running an ATS scan on shortwave.

As I mentioned early in this review, I must set realistic expectations when reviewing self-powered radios. When most consumers consider a self-powered radio, they’re seeking a simple, basic radio that will provide information during times of need: power outages, natural disasters, or while hiking, camping, boating, or simply in an off-grid setting.

Internally-generated noises––especially on the AM band––will disappoint radio enthusiasts. If Tivdio could address this in future iterations of the HR-11S, it would substantially improve this unit.

My overall impression is that the HR-11S is chock-full of features, but none of them are terribly refined. There are even some internally-generated noises in Bluetooth mode, which really surprised me as it seems like an oversight by engineering.

I see the Tivdio HR-11S is a bit of a “Swiss Army Knife” of a self-powered radio. It has more functionality and connectivity than any other self-powered radio I’ve tested to date. Its features will, no doubt, appeal to the average consumer––and a quick look at Amazon reviews seem to support this theory. As a radio enthusiast, however, I would pass on the HR-11S until the internally-generated noises have been addressed.

Click here to view to the Tivdio HR-11S on Amazon.com (affiliate link supports this site).

See coupon codes below.

For those who are interested, Tivdio passed along several coupon codes that SWLing Post readers can use to save money, should they decide to purchase the HR-11S:

For a 5% discount, use code:

Video: Comparing the SDRplay RSP1A and Airspy HF+ on HF & MW

Many thanks to SWLing Post contributor, Ivan Cholakov, who shares the following video where he compares the SDRplay RSP1A and the AirSpy HF+ software defined radios on shortwave and mediumwave:

Click here to watch on YouTube.