SDRplay announces the RSPduo – A 14-bit Dual Tuner SDR
Today at the Dayton Hamvention, SDRplay Limited is announcing the launch of a new Software Defined Radio product – the RSPduo.
The RSPduo is a radical new addition to the RSP line of SDR receivers from SDRplay. Architecturally, it is different from any previous RSP in that it features dual independent tuners, both piped through a single high-speed USB 2.0 interface.
The SDRplay RSPduo is a dual-tuner wideband full featured 14-bit SDR which covers the entire RF spectrum from 1kHz to 2GHz giving 10MHz of spectrum visibility. Initially using Windows based ‘SDRuno’ supplied by SDRplay, you can simultaneously monitor two completely separate 2MHz bands of spectrum anywhere between 1kHz and 2GHz.
Superficially the RSPduo looks identical to the highly popular RSP2pro and will be able to operate in a very similar way.
However, it also allows a completely new and exciting set of usage scenarios such as:
Simultaneous monitoring of two widely spaced bands – e.g. 40m (HF) and 2m (VHF)
Mixing and matching applications simultaneously – e.g. ADS-B and ATC scanning
Phase and time coherent demodulation of two receivers
Scenario 3 is very difficult to achieve with two separate USB devices because of the uncertainty of USB latency. The RSPduo overcomes this limitation because all traffic goes through a single USB interface, thus enabling the possibility of the development of various types of diversity demodulation such as: spatial, frequency and polarisation which can bring
huge benefits in terms of improved performance.
Jon Hudson, Marketing Director at SDRplay commented:
“As well as adding a second independently controlled tuner, which in itself, offers a whole new set of exciting usage possibilities, the SDRduo features 14bit ADCs and a completely re-designed RF front end. These changes provide better RF selectivity and even more dynamic range, offering outstanding performance under extremely challenging reception conditions. The combination of performance and features makes the RSPduo our highest spec RSP yet and sets a new benchmark in the sub $300 SDR market”
Due to its exceptional combination of performance and price, the RSP family of receivers have become very popular and the RSPduo provides the next level of functionality for both amateur radio enthusiasts as well as the scientific, educational and industrial SDR community.
As well as being demonstrated at Hamvention, the RSPduo is available direct from SDRplay or via SDRplay’s network of channel partners and resellers
The RSPduo is expected to retail at approximately $279 USD (excluding taxes) or £199 GBP (excluding taxes).
About SDRplay: SDRplay limited is a UK company and consists of a small group of engineers with strong connections to the UK Wireless semiconductor industry. SDRplay announced its first product, the RSP1 in August 2014
After the initial flurry of reports, interest, and purchases of the XHDATA D-808 portable receiver by radio enthusiasts, the door on USA shipments seems to have slammed shut.
This fine DSP-based portable went live in early December 2017 for USA purchasers when it was offered by AliExpress for $69.98 with shipping. Later, the RadiWow site started selling the radio for nearly the same price including USA shipping.
Now in mid-March 2018, the D-808 is nowhere to be found on AliExpress:
Sure, the RadiWow firm still ships the D-808 to the USA, but for a ridiculous “we don’t really want your business anyway” price. (A company that has a product page with “LOGO” in the corner is certainly not paying attention…perhaps they meant to enter “USD $20” as the cost? :^)
My hope is that XHDATA is working on an exclusive USA distributorship, such as Kaito Electronics Inc. has in this country for Kaito radios, or perhaps the D-808 will eventually be found only on Amazon USA. Maybe the highly regarded EBay seller Anon-Co (Anna) is at work behind the scene to offer this model exclusively.
What’s going on here? Please leave your thoughts in the comments section below.
Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.
As reported recently on the SWLing Post that the Airspy HF+ would be available “really, really, really soon”, the rumor has become reality–this new SDR receiver is for sale on Airspy’s main sale site www.Itead.cc.
The direct link for purchase is: https://www.itead.cc/airspy-hf-plus.html. The price in US dollars is a very reasonable $199.00, considering the high performance evident by the few test units “in the wild” recently.
There was an initial $50-off coupon code available first come, first served this morning for the first 100 orders. These were snapped up quickly; I was fortunate to make it into that limited group and I saved $50 each off a couple of HF+ units. My intent is to pair them up for full coverage of the medium wave band–while recording I/Q WAV files)–using two receiver “instances” within Studio 1 or SDR-Console software. (The alias-free bandwidth of the HF+ is a modest 660 kHz, a trade-off this receiver makes to deliver high performance at a low price.) I expect a EXTIO DLL file to be available soon for use in EXTIO software like Studio 1 (or the EXTIO version of SDRuno which I also use).
I plan to be comparing the HF+ to my current Elad FDM-S2 SDR; based on specs and early user reports, it should be a tight race.
UPDATE: I’ve learned that the shipping timeframe for the HF+ is the beginning of December (approx. three weeks). There is also a U.S. distributor who is kindly offering a similar $50-off deal: https://v3.airspy.us/product/airspy-hfplus/
SDR manufacturer, Airspy, has a new product shipping “really really really soon” (per their website). The Airspy HF+ promises improved frequency agility through the use of high-performance passive mixers with a polyphase harmonic rejection structure. Airspy states that no external band filters are required as they are with many budget SDRs.
There are many other improvements over their previous iterations. Here’s the product information copied from the Airspy HF+ page on Airspy’s website:
The Software Defined Radio revolution brought great flexibility in VHF and UHF reception. Today we offer the best wide band receivers which address these needs. We also provide a high performance extension for weak-signal wide band reception on HF – something other competing solutions fail to address efficiently.
Airspy HF+ is a paradigm shift in high performance HF radio design. It is a joint effort between Airspy, Itead Studio and a top-tier semiconductor company to build a state of the art SDR for HF and VHF bands.
Like most high-end HF receivers, the HF+ uses very high dynamic range ADC’s and front-ends. But unlike the current offerings in the market, it also brings more frequency agility by using high performance passive mixers with an excellent polyphase harmonic rejection structure. No external band aid filters are required like the lower end HF receivers, which makes it the ideal companion for light portable high performance operation.
Both the architecture and level of integration achieved in this design allow us to bring top performance reception at a very affordable price.
All the major SDR software is supported. Check the download page.
State of the Art SDR streaming technology!
We concentrated state of the art DSP and networking techniques into our SpyServer software to allow multiple users to stream high quality IQ data from the same receiver at the same time. No compromises in the quality were made like it is usually done in Web SDR interfaces. You get actual IQ data you can process with your plugins and extract the last bit of information out of it.
The server software is highly scalable and can run on computers as small as the $7 Orange Pi Zero to top end 64bit servers with multiple cores/cpus, including the popular Raspberry Pi series.
Airspy HF+ achieves excellent HF performance by means of a low-loss band filter, high linearity LNA, high linearity tunable RF filter, a polyphase harmonic rejection (HR) mixer that rejects up to the 21st harmonic and multi-stage analog and digital IF filtering.
The 6 dB-stepped AGC gain is fully controlled by the software running in the DSP which optimizes the gain distribution in real time for optimal sensitivity and linearity. Harmonic rejection is a key issue in wide band HF receivers because of the large input signal bandwidth of the input signal. The output of the IF-filter is then digitalized by a high dynamic range sigma delta IF ADC for further signal processing in the digital domain.
Excellent VHF performance is also achieved by using optimized signal paths composed of band filters, high linearity LNAs with a stepped AGC, a polyphase harmonic rejection mixer and IF filters optimized for their respective bands.
The amplifier gain is switchable in 3 dB-steps and fully controlled by the AGC running in the DSP. The RF signal is converted to baseband by a high linearity passive mixer with a polyphase harmonic rejection structure. The low-IF signal is then converted into the digital domain by the same IF ADC used in the HF chain.
The IF analog to digital converter (ADC) is a 4th order multi-bit noise shaping topology; it features very high dynamic range and linearity. The IF-ADC sampling rate is determined by a control algorithm running in the embedded DSP. This advanced technique adjusts the sampling rate depending on the tuning frequency with the goal of avoiding the disturbances and spurs generated by the switching discrete-time sections of the IF-ADC.
Digital Down Converter
Once the IF signal is digitalized, the high sample rate I/Q stream is then frequency translated and processed with cascaded CIC and FIR decimation stages. After every stage, the sample rate is reduced and the resolution increased. The final signal at the output has 18bit resolution and an alias rejection performance of 108 dBc. The data is then scaled to 16bit and sent to the Micro-Controller for streaming over USB.
The main advantages over techniques from the legacy super-heterodynes up to the now mainstream direct sampling is that the whole receiver chain is well protected against out of band blockers while still relaxing the RF filtering constraints, making it simple and cost effective.
The natural filtering of the sigma-delta ADC combined with the excellent linearity and sensitivity of the analog chain reaches an unprecedented level of performance and integration.
Use it over the network!
Connect as many SDR applications as needed to the HF+, over the Internet or in your own local network with near zero latency thanks to the new SPY Server software.
This setup basically brings all the flexibility of Web based SDRs while still benefiting from the full power of desktop applications. The IQ data is processed in the server with state of the art DSP and only the required chunk of spectrum is sent over the network. What is sent is the actual IQ signal, not compressed audio. This means you can use all your favorite plugins to process the IF, eliminate noise and perform heavy lifting of the signals as you are used to do with locally connected SDR’s.
We have a tradition of building multi-tools, so we made sure the SPY Server runs on 32/64bit Windows and Linux on Intel and ARM processors without any compromises. Low cost Raspberry Pi 3 and Odroid boards are in the party.
HF coverage between DC .. 31 MHz
VHF coverage between 60 .. 260 MHz
-140.0 dBm (0.02 µV / 50 ohms at 15MHz) MDS Typ. at 500Hz bandwidth in HF
-141.5 dBm MDS Typ. at 500 Hz bandwidth in FM Broadcast Band (60 – 108 MHz)
-142.5 dBm MDS Typ. at 500 Hz bandwidth in VHF Aviation Band (118 – 136 MHz)
-140.5 dBm MDS Typ. at 500 Hz bandwidth in VHF Commercial Band (136 – 174 MHz)
-139.0 dBm MDS Typ. at 500 Hz bandwidth in the upper VHF Band (> 174 MHz)
+15 dBm IIP3 on HF at maximum gain
+13 dBm IIP3 on VHF at maximum gain
110 dB blocking dynamic range (BDR) in HF
95 dB blocking dynamic range (BDR) in VHF
150+ dB combined selectivity (hardware + software)
120 dB Image Rejection (software)
Up to 660 kHz alias and image free output for 768 ksps IQ
18 bit Embedded Digital Down Converter (DDC)
22 bit! Resolution at 3 kHz channel using State of the Art DDC (SDR# and SDR-Console)
Open source, multi-platform user mode driver libairspyhf on github
No price point has yet been made public–at least, none that I have discovered. Of course, we’ll post shipping and pricing details when they become available. Follow the tag AirSpy for more. Check out the Airspy website for full details and documentation.
As a result of numerous responses to another video I posted on my YouTube channel a few weeks ago, I have now prepared a video that gives you a detailed look at using the Behringer Xenyx Q802 USB mixing console.
The unit is wired up to four receivers, then sent off to a pair of powered speakers. I cover how the mixer is connected to the radios and the speakers, explain the various controls available to the shortwave radio listener and amateur radio operator, the advantages of using this system in the radio shack, and offer a few tips when buying a mixing console such as this Behringer unit.
If you have a few receivers kicking around in your radio shack, this is one way to hook them all together and send their audio on to your favourite monitoring speakers. Thanks for taking the time to watch this little video. As always, comments and feedback are most welcome.
73 and good DX to you all,
Rob Wagner VK3BVW
Rob Wagner, VK3BVW, is the author of this post and a regular contributor to the SWLing Post. He also blogs at the Mount Evelyn DX Report. He also has a grab bag of assorted radio videos to check out at his YouTube Channel.