Yearly Archives: 2017

Airspy’s latest: The Airspy HF+ SDR

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:

(Source: Airspy)

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.

HF Tuner

Airspy HF+ achieves excellent HF performance by means of a low-loss band filterhigh linearity LNAhigh 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.

VHF Tuners

Excellent VHF performance is also achieved by using optimized signal paths composed of band filtershigh 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.

IF Sampling

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.

Architectural Advantages

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.

Technical specifications

  • 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)
  • +10 dBm Maximum RF input
  • 0.5 ppm high precision, low phase noise clock
  • 1 PPB! frequency adjustment capability
  • Very low phase noise PLL (-110 dBc/Hz @ 1kHz separation @ 100 MHz)
  • 2 x High Dynamic Range Sigma Delta ADCs @ up to 36 MSPS
  • No Silicon RF switch to introduce IMD in the HF path
  • Routable RF inputs
  • Wide Band RF filter bank
  • Tracking RF filters
  • Sharp IF filters with 0.1 dB ripple
  • Smart AGC with real time optimization of the gain distribution
  • All RF inputs are matched to 50 ohms
  • 4 x Programmable GPIO’s
  • No drivers required! 100% Plug-and-play on Windows Vista, Seven, 8, 8.1 and 10
  • Industrial Operating Temperature: -45°C to 85°C

Typical Applications

  • High Performance Networked HF/VHF Radio
  • Ham Radio (HF + 2m)
  • Short Wave Listening (SWL)
  • AM DX
  • FM DX
  • VHF-L TV DX
  • Remote Telemetry Radio Receiver
  • Low Bands IoT

Supported Operating Systems

  • Windows Vista, 7, 8, 8.1 and 10
  • Linux
  • *BSD
  • OSX

Supported Hardware

  • Intel compatible PC
  • Raspberry Pi 2 and 3
  • Odroid C1, C2 and XU4
  • Many other Single Board Computers (SBC)

Minimum hardware requirements

  • 1GHz Pentium or ARM
  • 1GB of RAM (to run your own OS, HF+ barely needs 1MB of memory)
  • High speed USB 2.0 controller

Supported Software

Developer API

  • 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.

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VORW Radio International’s Updated Schedule

Many thanks to SWLing Post contributor TheReportOfTheWeek who shares the following update:

Hello Thomas, a lot of the broadcast times for VORW Radio International have changed so I would like to submit an updated schedule for your readers! All changes are in Bold.

Each broadcast features a mixture of my commentary and listener requested music. It’s the listeners who choose the playlist in every show, so you are guaranteed to hear a great variety of music! Hope you can tune in!

Thursday 2300 UTC – 9955 kHz – WRMI 100 kW – South America
Friday 0000 UTC (Thu 7 PM Eastern) – 7730 kHz – WRMI 100 kW – Western North America
Friday 0100 UTC – 9395 kHz – WRMI 100 kW – North America
Friday 0100 UTC – 9455 kHz – WRMI 100 kW – Central America
Friday 0100 UTC – 7490 kHz – WBCQ 50 kW – North America
Sunday 1600 UTC – 9400 kHz – Spaceline – 150 kW – Europe / Middle East
Sunday 2100 UTC – 9395 kHz – WRMI 100 kW – North America

Questions, comments, reception reports and music requests may be sent to [email protected]

Reception reports will receive a QSL!

Thanks for the update and keep up the great work!

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From the Isle of Music & Uncle Bill’s Melting Pot, Nov 12-Dec 2

From the Isle of Music episodes for November 12-December 2:
1. For the week of November 12-18, our special guests are from Manguare, one of the leading bands in Cuba’s Nueva Trova movement. We will be spending the hour with them with a lot of music.
2. For the week of November 19-25, we will rebroadcast on of our favorite episodes from 2016, which includes award-winning Jazz piano virtuoso Harold López-Nussa and other good things.
3. For the week of November 26-December 2, we will feature some interpretations of part of Schubert’s Trout Quintet lead by Cuban pianist Frank Fernandez along with an part of an intriguing album from the 1980s, Leningrado, featuring moments by several of Cuba’s Jazz elite from the time.
Four opportunities to listen on shortwave:
1. For Eastern Europe but audible well beyond the target area in most of the Eastern Hemisphere (including parts of East Asia and Oceania) with 100Kw, Sunday 1500-1600 UTC on SpaceLine, 9400 KHz, from Kostinbrod, Bulgaria (1800-1900 MSK)
2. For the Americas and parts of Europe, Tuesday 0100-0200 UTC on WBCQ, 7490 KHz from Monticello, ME, USA (Monday 8-9PM EST in the US) NOTE THAT UTC CHANGED FOR B17 BUT EASTERN US TIME IS STILL THE SAME.
3 & 4. For Europe and sometimes beyond, Tuesday 1900-2000 UTC and Saturday 1200-1300 UTC on Channel 292, 6070 KHz from Rohrbach, Germany.

Uncle Bill’s Melting Pot episodes for November 12-November 26

Here is fair warning of the next 3 episodes of Uncle Bill’s Melting Pot:
Episode 36 (November 12): Funky music from Benin
Episode 37 (November 19): German versions of hits from other countries
Episode 38 (November 26) : Bluegrass meets Hard Rock
Sundays 2300-2330 UTC (6:00PM -6:30PM Eastern US) on

WBCQ The Planet 7490 KHz  from the US to the Americas and parts of Europe

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Radio Romania International launches a weekly “experimental” show in Hebrew

Many thanks to SWLing Post contributor, David Iurescia (LW4DAF), who writes:

Radio Romania Internationas has started a new service every Sunday in Hebrew language, since October, 29th. All the info here:

http://www.rri.ro/pages/october_29_2017_update-2571263

“As of Sunday, October 29, RRI broadcasts a weekly, experimental show in Hebrew, devoted to Jews born in Romania and their families, but also to all Hebrew speakers who are interested in learning about Romania. The show will be broadcast every Sunday, from 7:05 pm to 8 pm Romania’s time, on short waves and via the internet. Also, contents in Hebrew will be available on RRI’s web site, Android and iOS applications, on Facebook, Twitter and SoundCloud. RRI boast a rich experience in producing shows devoted to the hundreds of thousand of Jews originating from Romania, who since 1990 have had the opportunity to listen to a show in the Romanian language. Their descendants, now at the third generation after Aliyah, the immigration of Jews from the Diaspora to the Land of Israel, speak Hebrew and their ties with their parents’ and grandparents’ birth country should be developed and maintained, including with the help of RRI.”

Wow! Thank you for the tip, David! I’m simply amazed at the amount of content Radio Romania International produces.  Certainly one of my favorite shortwave broadcasters.

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PNG Minister for Communication wants to invest in shortwave

(Source: The Post Courier via Bill Lee)

Minister for Communication, Information Technology and Energy Sam Basil wants all 22 provinces to have short wave frequency radio stations.

He said this during the Central Province assembly induction program last week Friday in Port Moresby.

“My role as the minister is to make sure that we go back to all the 22 provinces to make sure that we revive the radio stations,” Mr Basil said.

He said most of the radio stations currently using frequency modulation (FM) face the problem of signal loose in the rural settings as it is only powered by repeater and could not be able to penetrate when it meets obstacles.

“This is to ensure that people are kept informed and in tuned with the government of the day,” Mr Basil said.

[…]“I want to go short wave and we want to bring back to all the provinces capital in Papua New Guinea through National Broadcasting Corporation so that people in the mountains can have excess to communication,” Mr Basil said.

Click here to read the full article at The Post Courier.

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Universal Radio taking pre-orders for the 8th Edition of the WWLG


Many thanks to SWLing Post contributor, Troy Riedel, who notes that Universal Radio is now taking pre-orders for the 8th edition of the Worldwide Listening Guide by John Figliozzi.

Click here to check it out on the Universal Radio website.

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Rolf’s PL-680 modification allows external antenna on LW and MW

The Tecsun PL-680

Many thanks to SWLing Post contributor, Rolf Snijder, who writes:

I did a modification today on the Tecsun PL-680 [which allows for an] external antenna on LW and MW.

The internal ferriet is also working, but on my active loop, MW and LW is now working !

So far away stations I can now receive on this portable radio.
It is only a560 pF capacitor added!

Click to enlarge.

Click to enlarge.

It works on LW and MW now with this mod.

FM is less now I think, maybe I will put it on a switch so I can turn it off.
And now also the ferrite is still working, so I hope to find a solution for that.

Many thanks for sharing your modification and photos, Rolf! Check out Rolf’s other PL-680 mod by clicking here.

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