Tag Archives: SDR

Guest Post: A review of the Icom IC-R8600 wideband SDR receiver

Many thanks to SWLing Post contributor, Dan Robinson, who shares the following guest post:


ICOM’s IC-R8600:   Can this mega-radio stay in the ring with big gun “legacy” receivers when it comes to shortwave band reception?

by Dan Robinson

When ICOM rolled out its new wideband receiver, the IC-R8600, I immediately took an interest in it.  I have been primarily a hardcore DX’er and SWL and avoided purchasing wideband receivers, including the predecessor IC-R8500, because they were limited in areas such as selectivity.

My experience with ICOM includes owning a IC-R71A and R72, both of which I found to be strong performers, as well as a IC-R75.  The R75 as everyone knows established a reputation as an excellent receiver that delivered bang for the buck, including for example 1hz readout and extreme stability.

In its design decisions with the 8600, ICOM clearly intended to hit it out of the park, taking a huge step from the 8500.  That can be seen in the amazing color 4.3 inch LCD display with fairly fast spectrum scope and waterfall displays, coverage from 10 kHz to 3 gHz, decoding capability in multiple protocols, (Baudot RTTY, D-STAR™, NXDN™, dPMR™, DCR (Digital Communication Radio) and APCO P25, and the combination of SDR and superheterodyne circuitry, with 2000 memories.

The new Icom IC-8600 at the 2017 Hamvention

At this point, there have been numerous reviews of the 8600, and videos are all over YouTube showing the basics of its operation and features.  It has numerous flexibilities selected from the front panel and within the menu system.  The ability to record directly to SDHC cards eliminates the need to attach an external solid state recorder (over the course of my DX career I accumulated many of these).  I can’t say enough about this capability which automatically keeps fully labeled logs.

Other features include ICOM’s wonderful Twin Passband Tuning, combined with the ability to adjust filters 1/2/3, adjustable attenuation, Digital AFC, tone controls, noise blanker digital noise reduction, speech enunciator, main tuning dial tension adjustment, synchronous L/U/Double sideband, adjustable panel brightness . . . in short, just about everything one would think should be included in a 21st century receiver of this kind, ICOM put in the 8600.  The firmware update released recently (1.30) added the capability to use the radio’s IQ output with HDSDR software, which means that the receiver is now not only a standalone but also functions easily with a PC.

Since the 8600 has been on the market for some time now, I discussed with Thomas Witherspoon of SWLing Post, the idea of obtaining an 8600 for the specific purpose of comparing it to some of the top receivers in my collection.

JRC NRD-515

At the current time, that list includes a JRC NRD-545, the Drake R-8 (original version purchased in 1993), JRC NRD-515, Watkins Johnson 8718A/MFP, Cubic R-2411, and a McKay Dymek DR-33C.  All of the radios in my shack use a Wellbrook 1530 loop, fed through a RF Systems DA-8 Distributor/Amplifier which maintains signal levels from all outputs.

Watkins Johnson 8718A/MFP

A surprising outcome of my comparisons of the 8600 to these radios is that my appreciation of the qualities of these older receivers was actually re-ignited–so much so that some that had been on my ‘to sell’ list are now back in the ‘keepers’ column.  This is not as much a criticism of the 8600, as it is a reaffirmation of the quality that was built in to some of the great receivers of yesteryear.

Because my collection actually extends across 2 or 3 rooms, moving the 8600 away from my central receiver “stack” was not possible, so testing comparisons were limited to the sets mentioned above.  I would have liked to compare the 8600 with, for example, some classic tube receivers (HQ-180A, Eddystone 830/7), but they have been mostly inactive and located away from incoming antenna inputs.

Here in Potomac, MD outside of Washington, DC, the addition of the Wellbrook a few years ago, after years suffering with long wires, fundamentally changed a difficult situation. Signals were boosted, noise reduced.  I wish things had continued this way.  Unfortunately about a year ago, my area began to be plagued by a troubling ignition-type buzz, source unknown, targeting 11,500 to 12,100 khz though noticed elsewhere in the shortwave bands. It has continued, usually worse in summer than in winter.

I begin with this to underscore what I noticed as a high point for the 8600:  its Noise Blanker and digital noise reduction are in my opinion quite effective, so much so that when properly adjusted, they can eliminate troublesome ignition-type noise.  While NR is useful, as noted in other reviews it needs to be used carefully so as not to introduce too much digital suppression.

Here is an example of NB and NR in use against severe ignition-type noise at my location:

Click here to view on YouTube.

In August of 2017, I had my first experience tuning a 8600 at a DXpedition in Ohio.

So, I had a basic grasp of the various controls — the A/B/C knobs, and the menu system.  When I received my review unit from ICOM last November, I was up and running quickly, but still puzzled over some aspects of the receiver’s operation.

Thanks to Dave Zantow who alerted me to a possible issue involving firmware 1.30 which appeared to introduce an increase in audio harshness (ICOM has been alerted to this).  Dave also had suggestions (see his full review of the 8600 and other receivers on his site) about audio adjustment and speakers, and tweaking of the front display to make maximum use of the Peak and Waterfall settings.  Dave emphasizes that careful adjustment is required of the 8600’s tone controls and AGC decay settings to get the most out of the receiver.

Because it is among the receivers in my shack in close proximity to the 8600, I chose to perform a number of tests comparing the ICOM to the Japan Radio Company NRD-545.  As everyone knows, the 545 was the last in JRC’s prosumer line of receivers.  It is feature-rich — JRC threw everything into this receiver.  But one issue followed JRC receivers through the 5xxxx series — noisy audio.  After finally acquiring a 545 some years ago (a high serial number unit formerly owned by the late Don Jensen) I jumped on that bandwagon of criticisms about the 545’s audio.  However, in terms of sensitivity and numerous tools to hear and process signals, the receiver remains among my favorites, and this remains the case after my comparisons with the 8600.

When I compared signals heard by the 8600 with the 545, I found that while the JRC does have that ‘DSP’ sound, it was in many situations actually clearer than the ICOM. That was the case even when following advice on adjusting the 8600’s tone controls and AGC.  The following two videos compare the 545 and 8600 on 5,905 khz and 17,655 khz.  A third shows the receivers on 6,040 khz demonstrating effectiveness of their notch filtering capabilities:

ICOM IC-R8600 v NRD-545 on 5,905 kHz

Click here to view on YouTube.

ICOM IC-R8600 v NRD-545 on 17,655 kHz

Click here to view on YouTube.

ICOM IC-R8600 v NRD-545 notch on 6,040 kHz

Click here to view on YouTube.

My next comparison was the Drake R8.   Little can be said about the Drake R8xxxx series of receivers that hasn’t been said.  That superb Drake audio, established with the R8 and continued through the R8B, puts these receivers at the top of the heap and makes stations stand out.  So, it’s little surprise then when compared to the 8600, which is an SDR in the HF range up to 30 mhz or so, the R8 still sounded superior on many, though not all, stations.  Use of the SYNC mode (not adjustable on the original R8, but was on the R8A/B) also improves recoverable detail on the Drake.

The following video shows the 8600, 545 and finally the R8 on 5,995 khz (Mali), and the three receivers compared on 9,650 khz (Guinea), and a third comparing the 8600 with the full range of receivers in my main receiver stack, tuned to 9,415 khz which at the time was China Radio International.

Click here to view on YouTube.

Click here to view on YouTube.

Click here to view on YouTube.

Despite what some critics have said, I believe that the 8600’s synchronous detection modes are actually pretty good, helping with fading and stabilizing signals. I think the ICOM’s sync is certainly superior to what I experienced with the IC-R75. I would rate the SYNC on the AOR 7030+ superior to the 8600, with the NRD-545 a bit behind the 8600.

Acquired about 2 years ago, my AOR-7030+ is a late serial number version of this fantastic receiver.  If I were to sell every radio in my shack but 5, the 7030 would not leave.  Put simply, it is among the top shortwave receivers ever made, with off-the-charts audio, and if one has the rare NB7030 card, amazing notch and other capabilities.  Comparing the 7030 to almost any other shortwave receiver ever made is like putting a Ferrari on the track with the competition.  The audio, and reception tools are just that good.

At the same time, in the 8600 ICOM has produced a receiver that has as many of the essential tools required to manipulate and clarify signals as exist.  The twin passband tuning continues to be superb.  Being able to vary bandwidth in conjunction with the PBT, and do so even in SYNC mode, further enhances reception powers.  Combine this with the ability to actually see signals on the 8600’s beautiful color LCD — we’re getting pretty close to the ultimate receiver (though I would love for someone to drop the successor to ICOM’s IC-R9500 on my front doorstep).

The following videos compare the 8600 to the same full range of receivers, ending with the Watkins Johnson 8718A/MFP, all tuned to 5,935 khz, followed by a comparison of receivers tuned to 5,000 khz

Click here to view on YouTube.

Click here to view on YouTube.

In the following videos, I compare the 8600 to other receivers 11,810 khz (BBC) which shows
the superb audio of the Drake R8xxxx series, yet the 8600 does quite well, and another video
compares the 8600 with the 545 and R8 tuned to 6,070 khz.

Click here to view on YouTube.

Click here to view on YouTube.

In the months that I have had the 8600, I did some comparisons with other receivers, among them my Watkins Johnson 8718A/MFP, which you saw in several videos.  WJs prior to the 8711/HF-1000s were built like boat anchors and are QUIET.  WJ, Cubic and similar sets manufactured for government and intelligence agencies, shared superb sensitivity, and most cases, excellent audio.

Comparisons of the 8600 on shortwave frequencies had the so-called Premium radios out front. The ICOM clearly shined when it comes to modern signal processing and adjustment tools such as PBT, Notch, and infinitely variable selectivity.

Summary

So, here’s a summary of my impressions after weeks of testing the ICOM IC-R8600 against some of the top gun receivers of yesteryear.

The 8600 scores a 10 on reception tools that are useful — though not crucial in these days of waning shortwave broadcasting activity — in producing and processing listenable audio:  Twin PBT, Notch and Auto-Notch, Variable Bandwidths (though limited at the high end to 10 kHz), Pre-Amp and Attenuation, and that beautiful color LCD that allows one to see signals.

Predictably, the 8600 doesn’t blow away premium receivers that were manufactured to pick up the signal equivalent of butterflies and targeted government and spy agencies, and it also does not out-perform a range of other classic receivers whose reputations are well-established.

From a sensitivity and audio perspective, there is no real competition with the Drake R8, which time and time again excels in producing superior easy-to-listen audio.  And the same holds for the AOR 7030+.

JRC’s NRD-515 more than holds its own and in many cases exceeds the 8600 in signal sensitivity, and producing listenable audio, despite its selectivity limitations.

The NRD-545 — maligned by critics for its DSP audio, often produced highly-listenable audio even in comparison with the 8600.  The ICOM and the 545 share features that provide tremendous flexibility, the tools required to slice and dice signals.  If the JRC NRDxxx receivers were the modern equivalent of such boat anchor classics as the Hammarlund HQ-180A, the 8600 is certainly at the top of the heap when it comes to having those same tools in a 21st century receiver.

Audio Samples

I performed some additional audio only tests between the 8600 and NRD-545 on several frequencies.  In each, I carouseled from wide to narrow on the 8600, and did the same on the NRD-545.   Here are the results:

9,445 kHz

IC-R8600

NRD-545

9,420 kHz

IC-R8600

NRD-545

11,735 kHz

IC-R8600

NRD-545

11,810 kHz

IC-R8600

NRD-545

11,945 kHz

IC-R8600

NRD-545

15,580 kHz

IC-R8600

NRD-545

6,070 kHz

IC-R8600

NRD-545

9,650 kHz

IC-R8600

NRD-545

11,900 kHz

IC-R8600

NRD-545

You may have noticed that while on some examples the 8600 appears to sound better, the 545, with DSP technology born in the 1990’s is more than competitive with the ICOM.

Conclusion

In conclusion, with the 8600 we have a receiver that tunes up to 3 gHz, with highly flexible color scope, usable with HDSDR, with every tool imaginable for sifting through signals from 10 kHz up to 30 MHz, which is the area I have focused on for decades.

ICOM’s superb Twin PBT knocks out interference and narrows the heck out of any signal, with highly adjustable notch capabilities, customizable bandwidth functions, and what I consider to be highly effective noise blanking and noise reduction.  Add to this 2,000 memory channels, multiple antenna inputs, adjustable attenuation and AGC and you have far more than what is needed given the current state of shortwave broadcasting.

Here’s the tough question:  Would I recommend that a shortwave listener focused on what remains of listening in the SW bands purchase a 8600?  Or to put it another way: Is the 8600 that much of a better radio in the SW spectrum?  The answer has to be no.

Numerous receivers from the classics to even the latest portables with multiple selectivity flexibility (see the XHDATA D-808 or Eton Satellit) work for that.  The used market overflows with superb HF communications receivers.  Any of the Drake R8xxx series receivers, available on the used market for $400 to $1,000, now constitute overkill when it comes to reception in the MW to 30 mHz range.

But if you can project someday to having the time and patience to apply yourself to what is available above 30 MHz, and have the appropriate antenna(s) for those ranges, then by all means, the 8600 is the radio for you.  It is the Babe Ruth’s bat of the receiver world — AND it has numerous flexible tools (though one wishes that ICOM had included DRM capability).

As I finalized this review, I continued to wrestle with the decision of purchasing the 8600 that was so generously provided by ICOM.  You won’t read here what my final decision was–but anyone who is interested can contact me in coming days and weeks to learn the answer.

Last minute update  Just before this review went to press, I discovered an issue of concern:  when the 8600 was left on overnight, or for any period of multiple hours, upon awakening from “sleep” (screen off) mode, nothing but distortion is heard from the speaker.  The only solution was to perform a POWER OFF/POWER ON, after which normal audio was heard.  This issue was I brought to the attention of ICOM.

I want to thank Ray Novak and Faheem Hussain of ICOM for providing the 8600 used in this comparison, and for their patience as I encountered several delays completing my review and getting to print.  And thanks to Thomas Witherspoon without whose initial encouragement, this review would not have been possible.


Dan, thank you for an amazing IC-R8600 review and comparison with your benchmark commercial grade receivers! Thanks for taking the time to make thorough comparison video and audio recordings. Your guest posts are always most welcome on the SWLing Post!

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Ivan compares the AirSpy HF+ to the KiwiSDR

Many thanks to SWLing Post contributor, Ivan (NO2CW), who writes:

I have been running a public Kiwisdr server for a while and yesterday decided to plug in the new Airspy HF + into the same antenna for a side to side comparison. The antenna is an 80m dipole and the test was done during local afternoon, around 3 PM. I did not use any of the many new noise reduction features that are incorporated into both SDR Console 3 and the SDR web server. The 11 minute video is located here:

Click here to view on YouTube.

When I have the time I will run a similar test in nighttime conditions and also test the Airspy HF+ against a few other radios sitting on my desk.

Thank you for sharing this, Ivan!

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Addendum: More Notes on the HF+ SDR on Medium Wave & Long Wave

In my recent post on the AirSpy HF+ vs Elad FDM-S2, I commented on medium wave reception only.

This past weekend I swapped out the Wellbrook ALA1530S+ for another Wellbrook loop, the ALA1530LN Pro. This LN Pro model is less likely to overload receivers at my suburban Tacoma, WA location. Both AirSpy and Elad radios performed admirably with the LN Pro and it was nearly impossible to find any reception differences on medium wave.

Before the antenna swap though I experimented with inline attenuation modules (“bullets”), typically used in cable TV installations. I used the same sample rates on the SDRs as described in the previous article. After some tests with different attenuation levels, I came to the following conclusions during daytime comparisons:

FDM-S2 with ALA1530S+ loop, medium wave: needs a minimum of 6 dB attenuation to avoid overloading. Anything less causes saturation of the spectrum & waterfall, “crunching” overload noises, and minimal or no received signal.

HF+ with ALA1530S+ loop, medium wave: I had to search diligently to find any signs of false signals or overloading, but finally noticed a weak image or spur of a S-9+60 dB (-13.5 dBm) local station on 1560 that was appearing very weakly on 1270 kHz, mixing with the station on that frequency. Sometimes it was there, other times the spur or image would drop down and disappear, leaving the 1270 signal alone. If I added just 3 dB of attenuation in the antenna’s feed line, the interference from the 1560 station was gone for good. The S-9+60 dB station is a very strong signal; it’s impressive that the AirSpy HF+ deals with this and similar powerhouse signals so well.

Long wave: Below are two screen captures from my local long wave reception in the evening, made moments apart with each receiver.

FDM-S2

HF+

As you can tell, there are a half dozen or so additional signals seen on the HF+ below 200 kHz that do not appear on the FDM-S2. These extra spikes are images or spurs from medium wave signals that were missing from the FDM-S2’s reception–bravo Elad! However, the remaining spikes on both radios below 200 kHz seemed to be noise or interference.

Each receiver had roughly equal performance in the bulk of the long wave spectrum, when I did A-B comparisons on the same beacon signals. I’m not a LW or NDB DXer however, so I can’t claim any expertise on these frequencies. In short, though, both radios seem neck-and-neck from about 200 to 500 kHz.

The DXer of LW frequencies may want to look elsewhere for a better performing radio than either the FDM-S2 or HF+. SWLing Post reader Tudor Vedeanu has commented that the SDRPlay RSP1A  and the Eton E1 work very well at long wave.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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Brief Medium Wave Tests of the HF+ and FDM-S2 SDRs in a Suburban Location

The AirSpy HF+ is the new SDR on the block, but how does it compare to the Elad FDM-S2 which is more than 2-1/2 times its $199 price? My main interest is finding out how they compare in a very RF-quiet DXpedition setting, but today I compared the two briefly from my home in Puyallup, Washington (near Seattle).

The receivers were connected via a two-way antenna splitter to the output of a Wellbrook ALA1530S+ loop antenna. I monitored during mid-afternoon local time to ensure that all my MW locals in my suburban location would be at full power, for the best test of the radios’ overload performance. The Wellbrook active antenna is rather “hot” and sometimes overloads receivers during the daytime unless attenuation is added to the signal chain.

I noted there were no truly weak medium wave signals available during the session so comparing sensitivity wasn’t appropriate. However, the band was full of strong daytime MW signals.

It became apparent quickly that the upstart HF+ provides strong competition to the Elad SDR. Clearly, the AirSpy’s trade-off is bandwidth for raw performance at lower cost–approx. 660 kHz alias-free coverage versus about 6 MHz maximum for the Elad.

Using the same center L.O. (local oscillator) frequency, short recordings were made with both receivers on the same receive frequency, same bandwidth, AGC setting, etc.  To approximate the 660 kHz coverage of the HF+, I set the FDM-S2 to its 768 kHz sampling rate, the closest available setting to 660 kHz wide coverage.

Here are the results on 1540 kHz, just 10 kHz away from a strong signal on 1550:

AirSpy HF+ – 1540 kHz


Elad FDM-S2 – 1540 kHz

What’s wrong with the above audio picture? The FDM-S2 is clearly overwhelmed by the strong RF on the upper end of the MW band. Visually, the spectrum looked like this with the Elad:

Elad FDM-S2 waterfall/spectrum (1540 kHz)

The noise floor rose by approximately 20 dB due to the overloading. The HF+ showed a normal waterfall and spectrum display while tuning 1540 kHz:

AirSpy HF+ waterfall/spectrum (1540 kHz)

Let’s listen to two more audio clips, this time from 720 kHz which is adjacent to very strong 710 KIRO, the ESPN affiliate in Seattle:

AirSpy HF+ – 720 kHz


Elad FDM-S2 – 720 kHz

This time the difference is subtle, but I think you’ll agree there is a greater amount of “crunchy” background distortion noise on the FDM-S2 recording. I found this to be the case in each instance where I compared receivers on frequencies adjacent to strong locals.

I no longer own a Perseus SDR, but that receiver handles the entire MW band at this location without overload using the same Wellbrook ALA1530S+ loop.

I’d like to emphasize that these were brief, somewhat casual AirSpy HF+ vs. Elad FDM-S2 tests. I expect that in a more forgiving RF environment, both receivers will be equally adept and digging out weak weak and challenging DX signals. I plan to investigate this very scenario in a few weeks at a quiet location on the Oregon coast.

Side note: I have two HF+ units and they can operate concurrently without problems for full medium wave band coverage with HSDSR software, even when both are recording IQ WAV files.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

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Don shares spectrum recordings from northern Peru

Many thanks to SWLing Post contributor, Don Moore, who writes:

I’ve been traveling through northern Peru and I’ve made some SDR recordings along the way – medium wave, long wave, and some shortwave meter bands. I hope to eventually get through them all!

I have also uploaded some recordings to a shared Google drive so that other DXers can hear what the bands sound like in northeastern Peru, on the edge of the Amazon jungle. Maybe some of the blog readers would be interested in this. You will need the below link to see the SDR files and an explanatory document. I plan to add a few more once I get another hotel with a good Internet connection again.

Click here to download.

Fantastic, Don!  Thank you for sharing your spectrum recordings!

Post readers: If you don’t already have HDSDR installed on your PC, you’ll need to grab it here. HDSDR is free and can playback these spectrum recordings. Once installed, simply press the “play” button on the HDSDR console and point HDSDR to the downloaded spectrum file. You’ll be tuning through Peruvian spectrum in no time!

Also, check out Don Moore’s excellent blog: http://www.donmooredxer.com 

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The Airspy HF+ SDR: First impressions

Yesterday, I received a package in the mail containing the new Airspy HF+ software defined radio receiver.

It came as a bit of a surprise.

I’ve been busy lately with humanitarian work, the radio spectrum archive,  product evaluations and travels–not to mention an active family life. I had completely forgotten that about a month ago, I received a message from Airspy telling me that they had dispatched their latest SDR to me for evaluation.

This morning, I unpacked the box to find that the HF+ is a very compact, relatively dense little SDR in a metal alloy case/enclosure. I’m simply floored by the size. The case feels incredibly durable and of excellent quality.

The Airspy HF+ under my business card

In terms of footprint, dimensions are nearly identical to a business card. It’s about as thick as the typical USB memory stick.

The HF+ is so thin and compact compared with the Elad FDM-S2 (which is quite a compact SDR!)

Other than my RTL-SDR dongle, it’s by far the smallest SDR I’ve ever tested.

Though compact, it sports two SMA antenna inputs: one for HF, one for VHF.

The HF port is labeled as “H” and the VHF port as “V”

The Airspy HF+ uses a common micro USB for both data and power

The HF+ is the first AirSpy product I’ve ever put on the air.

I read the HF+ product description this morning while downloading SDR Sharp–it claims the HF+ is “plug and play”.

Turns out, that is no exaggeration.

The HF+ on top of the Elad FDM-S2 and WinRadio Excalibur

In fact, the entire SDR Sharp package downloaded in seconds, installed in seconds and the only thing I had to do after opening the SDR Sharp application was select “AirSpy HF+” from the product drop down menu.

I started the application and *boom* signals all over the place!

SDR applications, in general, have become so much easier to install over the years but I believe SDR Sharp may be the  quickest install I’ve ever experienced. About as easy and lightweight as the WinRadio Excalibur application. True plug and play!

I’ve had no time to properly evaluate performance–I just put this little SDR on the air.

Fortunately, propagation is cooperating this morning–I’m hearing both WWV Fort Collins and WWV Hawaii on 10 MHz. I’m really enjoying playing with the Airspy HF+ and re-familiarizing myself with SDR#. I had forgotten how responsive and intuitive the interface is–great user design.

My first impression?  I’m impressed. More to come…

Click here to read about the HF+ on the Airspy website

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A review of the SDRplay RSP1A software defined radio

 

Today, SDRplay, the UK-based manufacturer of affordable software defined receivers, announced a new addition to their product line: the SDRplay RSP-1A.

The RSP1A joins the SDRplay product line of the RSP2 ($169.95 US), and RSP2 Pro ($199.95 US). The new RSP1A will retail for $99.00 US.

But what of this SDR’s performance?  In a nutshell: as of today, I’d contend that the RSP1A will simply be the best SDR value on the market. End of story. There is nothing I know in the $99 price bracket that can beat it.

How do I know this?  I can make this statement with confidence because I have been involved with real-world testing and evaluation of the RSP1A Alpha, Beta, and production models since May. I took the RSP1A with me to Canada this past summer for field recordings with my laptop, and I’ve also evaluated the RSP at my home. Like a number of other reviewers, I’ve been intimately involved with putting the RSP1A through its paces. And let’s just say I like what I’ve seen.

I actually do quite a bit of Alpha and Beta testing for manufacturers. While it’s time-consuming volunteer work and requires meticulous attention to minor details, it gives me an opportunity to have meaningful positive impact on an upcoming product. Manufacturers that actively involve enthusiasts in their testing phase tend to produce better-quality products on the first run. Better products, of course, mean a better radio market with options for those only now discovering the mystery––and fun––of radio as well as DXing.

Since the RSP1A is essentially iterative agility on behalf of SDRplay, the RSP1A was surprisingly solid even in its early release. And try as I might, there were very few issues I ever needed to report back to the engineering team. SDRplay took each item of feedback seriously, logged it, and followed-up. Over the course of the evaluation period, SDRplay improved their dedicated SDR application SDRuno, as well.

In essence, the RSP1A hardware now in production and shipping has been thoroughly tested and is ripe-and-ready for your radio adventures.

I have not compared the RSP and RSP1A side by side; running two instances of SDRuno on the same PC has been problematic. To my ear, when I’ve tested one after the other, the RSP1A serves up slightly better sensitivity, perhaps due to a slightly lower noise floor. Also the RSP1A frequency stability is much improved over the RSP1.

Specifically, the following upgrades have been made per SDRplay:

  • ADC resolution increased to 14-bit native for sample rates below 6 MHz, increasing to 16 bits with decimation
  • Enhanced RF pre-selection (greater filter selectivity plus 4 additional sub-bands compared to the original RSP1) for reduced levels of spurious responses
  • Improved LNA architecture with variable gain––the RSP1 had just a single gain step
  • Improved intermodulation performance
  • Performance extended to cover 1kHz to 2 GHz with a single antenna port.
  • Bias-T facility
  • Improved frequency stability incorporating a 0.5ppm TCXO (software trimmable to 0.01ppm)
  • Selectable broadcast AM/FM/DAB notch filters
  • RF shielding within the robust plastic casing

Performance

Suffice to say, this budget SDR delivers, and users will be wooed by its stellar performance.

I’ve spent 95% of my evaluation time on the HF and mediumwave bands and I’ve been impressed with the receiver’s sensitivity, selectivity, and AGC control. The audio fidelity is also highly customizable since it’s pumping audio directly through your PC’s system.

I haven’t spent any time above the aviation bands (higher than 140 MHz); I have, however, tested the RSP1A thoroughly on the FM broadcast bands and found it a solid FM performer. Note, too, that SDRuno’s built-in RDS decoder window provides quite a lot of data.

I’m also pleased that I haven’t noticed any front-end overloading––this, despite the fact that during travel, I’ve used it in the vicinity of some powerful broadcasters.

Comparing to benchmarks

I’ve compared the RSP1A to the Elad FDM-S2 ($500), WinRadio Excalibur ($900) and Microtelecom Perseus ($900).

The WinRadio G31DDC “Excalibur”

But let’s be clear, here: this is not an “apples-to-apples” comparison since the RSP1A is a fraction of the cost of the others, and is also a wideband receiver (1 kHz to 2 GHz). The only other SDR I own that has VHF coverage is the FDM-S2, which tops out at 160 MHz.

Pricier HF-focused SDRs have distinct hardware advantages––especially in terms of filtering––that give them an edge over budget wideband SDRs. Still, in my comparisons, the RSP1A holds its own quite well.

Compared to the WinRadio Excalibur, for example, this SDR came fairly close in terms of sensitivity.  The WinRadio’s synchronous detector––which I consider to be the best in the business––was indeed more stable than that of the RSP1A. The RSP1A sync lock could falter a bit during a weak signal’s QSB dip compared with the Excalibur.

But again, HF SDRs in the league of the FDM-S2, Excalibur, and Perseus have the luxury of designing receiver architecture around a much smaller portion of the spectrum. If you are a hard-core DXer looking for uncompromised performance on the HF/MW bands, then you should invest in one of these benchmark SDRs. I have, and I’d never give one of them up.

With that said, even though I have these amazing benchmark SDRs at my disposal, I still purchased the original RSP1 (then at $159 US) years ago. Why?  For one thing, it’s more portable than the Excalibur or Perseus as it requires no external power supply (like the excellent FDM-S2, the RSP derives its power from the USB data cable). Additionally, I do like to play with frequencies above 50 MHz from time to time. The RSP offers up an all-in-one RF toolbox at a very affordable price. I don’t hesitate to throw the RSP in my pack and take it anywhere I’m travelling. If it gets damaged or lost, I’m only out $99––not $1,000.

Again, RSP1A’s bang-for-buck simply blows my mind.

Side note: I do wish someone would develop an accessory outboard filter box that could be implemented with budget wideband SDRs, thus providing, in a sense, a hardware “upgrade.” Something like the Elad SPF-08 preselector box designed for the FDM-S2

Any cons?

This review has been overwhelmingly positive because, frankly, the RSP1A is challenging to find fault with. Of course, if it carried a price tag of $600-900, I’d be much more critical of its performance as compared with my benchmark receivers in that same price class. I’d fully expect a robust preselector system, a bullet-proof front end, and performance that could match or surpass the benchmarks.

But for just $99? You simply can’t get that kind of hardware for that cost.  So SDRplay engineering cleverly pulls every bit of performance out of their receiver by focusing on their SDRuno application, which is optimized for this receiver.  And for that reason, it’s in a class by itself.

Admittedly, when SDRplay first introduced their application, SDRuno, I wasn’t the biggest fan. I found it rather quirky and a little cumbersome to use. SDRuno has come a long way, though; SDRplay has continuously improved it, and today, I prefer it to HDSDR and SDR console. SDRuno is much less cumbersome to use than it used to be, and the default window arrangement is pleasing (though I’d still like SDRuno windows to lock and act as one window as I flip through programs on my Win 10 PC). I even prefer SDRuno to Elad’s application in terms of ease of use.

If more AF/IQ recording features are added (virtual receivers, for example) it could even become my application of choice.

The great thing about the SDRplay RSP series, however, is that they’re supported by so many third-party SDR apps. If you don’t like the one you’re using, there are numerous others to chose from. SDRplay takes an affirmative stance that their hardware should be usable on as many platforms with as many applications as possible. Kudos to them.

Here’s a question I know I’ll be asked…

“I just purchased the RSP1. Should I upgrade?”

Good question! As you might guess, my answer is fairly simple and depends on your particular needs:

If you’re happy with the RSP1 and see no real benefit in the RSP1A upgrades above, don’t bother upgrading. Seriously…enjoy what you have! The RSP1 is still a sharp, capable, versatile little SDR and fully supported by SDRplay and its community. I’ve worked some incredible DX with mine over the past few years, and love it.

If you like the sound of the RSP1A and would appreciate the upgrades listed above, then go for it! After all, it’s only $99! Consider this: the price is less than that of my recently reviewed Digitech AR-1780 portable and less than the venerable Tecsun PL-660. Even with a modest external antenna, it will perform circles around these rigs.

If you need an excuse to justify the upgrade to the RSP1A, consider doing what I’m planning to do: give your RSP1 to a friend or someone interested in the hobby. Or, donate it to your radio club as a raffle prize. Then too, of course, you can snag a decent price for it by selling it on eBay or QTH.com.

Summary

While a little busy, I do enjoy the combined spectrum display option on SDRuno.

If you can’t tell, I’m most impressed with this latest offering from SDRplay. I can recommend it with confidence because you simply can’t beat the performance and features for the price.

If you’re considering the RSP1A as your first SDR, you’ll be happy to know SDRplay’s Mike Ladd has also amassed a healthy number of SDRuno instructional videos on YouTube as well. If you start with the first video, by the end of the series you’ll be adept at using SDRuno. Couldn’t be easier.

Think of it this way: The RSP1A is the sporty-but-affordable compact car of the SDR world. It delivers performance well above its comparatively modest price and is fun to operate. In terms of DX, it gets you from point A to point B very comfortably––and quite affordably!

With just $99, there’s no reason you can’t join the world of SDR––the RSP1A is a very accessible, very intuitive SDR start your exploration of the radio spectrum.

Click here to view the RSP1A at SDRplay’s website.

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