Tag Archives: SDRplay

SDRplay RSPdx update

(Source: Jon Hudson with SDRplay)

Happy new Year from all of us at SDRplay.

Here’s an update on additional software for the RSPdx. SDRplay’s SDRuno fully supports the RSPdx but it takes several weeks for other software to catch up to the capabilities offered on the other RSP models.

Simon Brown has released his latest version of SDR Console V3 which supports the RSPdx (Version 3.0.18 dated January 1st) over on https://www.sdr-radio.com/ (make sure you download the latest API 3.x from our downloads page first)

We have released an EXTIO plugin for the RSPdx which will enable the RSPdx to work with any EXTIO-based software (e.g. HDSDR) although it doesn’t support HDR mode. HDR mode will not be added and the source code for the plugin can be found on our GitHub repository (https://github.com/SDRplay/ExtIO_SDRplay) we will not be supporting the plugin source code or extending the plugins capabilities. They are all free to be modified.

It is important to note that the RSPdx ExtIO plugin does NOT, AND WILL NOT, support HDR mode. If you need HDR mode, then SDRuno is the best option. HDR mode requires the end application to work in a certain way and this is not something that can be controlled via the ExtIO protocol.

Work has also begun on supporting RSPdx for SoapySDR based applications such as Cubic SDR (again this won’t include HDR mode). A Gnu Radio source block for the RSPdx will follow.

We are working with Steve Andrew, author of the Software Analyser software programme (see https://www.sdrplay.com/spectrum-analyser/ ) to help get compatibility for the RSPdx – this is a slightly longer process so this will take several more weeks.

Regarding stocks of the RSPs, SDRplay and most of our resellers on www.sdrplay.com/distributors/ have plenty of stock of RSP1A and the RSPduo. However there continues to be a shortage of the RSPdx whereby many of the resellers have sold out of their first deliveries. SDRplay is queuing up their replacement orders on a first come, first served basis. We also have our own quantity planned in there to allow us to sell direct from our website. We still hope that by the end of January we will have supplied this second wave of RSPdx demand.

For newcomers to SDR, see also, the glossary and links included in the news item on: https://www.sdrplay.com/happy-new-year-and-an-rspdx-update/

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Mike compares the SDRplay RSPdx on mediumwave and longwave

Many thanks to SWLing Post contributor, Mike Ladd with SDRplay, who shares the following videos comparing the new RSPdx with a number of benchmark SDRs:

SDRplay RSPdx and ELAD FDM-S2 weak NDB station

SDRplay RSPdx and ELAD FDM-S2 medium wave selectivity

SDRplay RSPdx and Airspy HF+ Discovery medium wave selectivity

SDRplay RSPdx and Airspy HF+ Discovery weak NDB station

SDRplay RSPdx and Microtelecom Perseus medium wave selectivity

SDRplay RSPdx and Microtelecom Perseus weak NDB station

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A review of the SDRplay RSPdx wideband SDR receiver

SDRplay recently announced the latest product in their line of affordable 14 bit wideband SDRs: the SDRplay RSPdx.

For over two weeks now, I’ve had an early production model of the RSPdx here in the shack operating on a beta version of the SDRuno application.

In the spirit of full disclosure, SDRplay is a long-time supporter of the SWLing Post and I have alpha- and beta-tested a number of their products in the past. This early production RSPdx was sent to me at no cost for a frank evaluation, and that’s exactly what I’ll offer here. To be clear, while I am using beta software, this is not a beta SDR, but one from a first limited production run.

And thus far, I must say, I’m impressed with the RSPdx. 

Upgrades

The RSPdx has been introduced as a replacement for the RSP2 and the RSP2pro receivers. It has been updated and upgraded, with a completely new front-end design.

Here are the highlighted improvements and changes:

  • Performance below 30 MHz has been enhanced when compared to the RSP2/RSP2pro.
  • Performance below 2 MHz has been substantially upgraded. Through the use of the new HDR mode, both dynamic range and selectivity have been considerably improved.
  • There is now a BNC antenna connector on antenna C position instead of a HiZ port. Both A and B antenna ports are SMA like other RSP models.

Let’s face it:  those of us interested in low-cost SDRs are spoiled for choice these days. The market is chock-full of sub-$200 SDRs, especially if you include all of the various RTL-SDR-based SDRs and knock-off brands/models one can find on eBay.

Personally, I invest in companies that support radio enthusiasts for the long haul…those that do their own designs, innovations, and production. SDRplay is one of those companies.

SDRplay’s market niche has been providing customers with affordable, high-performance wideband receivers that cover an impressive 1 kHz to 2 GHz.

Wideband coverage can come at a cost. Unless you pay big money for a commercial-grade wideband receiver, you’re going to find there’s a performance compromise somewhere across the spectrum.  On the RSP2 series, those compromises would have been most apparent on frequencies below 30 MHz.

That’s not to say HF, MW, and LW performance was poor on the RSP2 series–indeed, it was quite impressive and well-balanced; it just didn’t stack up to the likes of the similarly-priced AirSpy HF+ and HF+ Discovery, in my humble opinion. Both little Airspy SDRs have wooed DXers with their impressive dynamic range and overall ability to work weak signals in the HF portion of the spectrum.

Neither of the AirSpy HF+ models are wideband receivers, but still offer a generous range:  9 kHz to 31 MHz and from 60 to 260 MHz––about 11.5% of the frequency coverage of RSP models. (Note that the Airspy R2 and Mini do cover 24 – 1700 MHz.) For shortwave radio listeners that also want to venture into the UHF and SHF regions, a wideband SDR is still required.

It’s obvious SDRplay’s goal is to make the wideband RSPdx into a choice receiver for HF and, especially, for MW/LW DXers. But have they succeeded? Let’s dive in…

Performance

As I say in most of my SDR reviews: doing comparisons with receivers that have so many features and adjustments is never easy. In other words, we want an apples-to-apples comparison, but it can be difficult to achieve, especially with new products.

I compared the SDRplay RSPdx with the WinRadio Excalibur and Airspy HF+ Discovery. Here’s how I set up my comparisons:

The RSPdx, Excalibur, and HF+ Discovery all used the same antenna in my tests––a large, horizontal delta loop antenna, via my ELAD ASA15 amplified antenna splitter. I’ve used this antenna splitter for years and can vouch for its equitable, lab-grade distribution of signal.

The RSPdx is not in full production at time of posting, thus application options are limited. Typically, I’d load comparison SDRs in SDR Console or HDSDR and test them with identical settings as well. At present, the RSPdx is only compatible with a beta version of SDRplay’s own application, SDRuno (which will come out of beta rior to the first major production run). The benefit of using SDRuno is that you unlock the full potential of the RSPdx, plus signal and noise numbers are incredibly accurate.

For each SDR in this comparison, I used their native/OEM application to give them the best possible performance.

I also matched filter settings and made an effort to match AGC and volume settings as closely as I could.

Additionally, I resisted the temptation of comparing my RSP2 with the new RSPdx because I didn’t want to run two simultaneous instances of SDRuno on the same computer––especially considering one was in beta.

Is this comparison perfect?  Probably not, but I did the best with the time I had available. I do intend to make further comparisons in the future.

Longwave performance

Via the RSPdx’s new “HDR” mode, both dynamic range and selectivity have been considerably improved with frequencies below 2 MHz. While I’ll fully admit that I’m not much of a longwave DXer, my very first listening session with the RSPdx started in this region of the spectrum.

In fact, the first evening I put the RSPdx on the air and confirmed that I was, indeed, in HDR mode, I noticed a small carrier via the spectrum display on 171 kHz. I clicked on it and quickly discovered it was Medi 1. The signal was faint, but I could clearly ID at least one song. This truly impressed me because I believe this was the first time I had logged Medi 1 on longwave from the shack.

I didn’t connect the Excalibur at that point to see if it could also receive the faint Medi 1 signal, but I imagine it could have. I’m pretty sure this would have been outside the reach of the RSP2, however.

I tried to explore more of the longwave band, but due to local RFI (I suspect an appliance in my home), most of the LW band was inundated with noise. With that said, I did grab three of my benchmark non-directional beacons.

Obviously, the RSPdx is a capable LW receiver.  I would like to spend more time on this band once I’ve tracked down the source of my local RFI.

Mediumwave/AM performance

In the past two weeks, I’ve spent many hours with the RSPdx on mediumwave.

We’re heading into the winter months in the northern hemisphere, and that’s normally when my listening habits head south on the bands.

In short: I find the RSPdx to be quite sensitive and selective on the mediumwave bands while the HDR mode is engaged. A major improvement over its predecessor.

I primarily compared the RSPdx with my WinRadio Excalibur on mediumwave since I consider the Excalibur to be a benchmark MW receiver. And, as you’ll hear in the screencasts below, the RSPdx truly gives the Excalibur a run for its money:

740 AM – RSPdx vs. Excalibur:

860 AM – RSPdx vs. Excalibur:

Note that my horizontal delta loop antenna is omni-directional, hence the tug-of-war you hear between stations in the clips above.

In truth, I could have done more to stabilize the signal on both of these fine SDRs, but I wanted to keep the comparison as fair as possible.

You might have noticed that both were running AM sync mode. It seems the sync lock on the RSPdx may have also improved––though I would need to do a direct comparison with the RSP2 to know for sure––but in terms of stability, I still found that the WinRadio Excalibur was superior. Mind you, the Excalibur is a $900 – $1,000 receiver and has the strongest synchronous detector of any radio I’ve ever owned.

Shortwave/HF

SDRplay notes on the preliminary specifications sheet that the RSPdx has been “enhanced” when compared with the RSP2 series.

And, after having spent two weeks with the RSPdx on the shortwave bands, I would say this is a bit of an understatement. For although I haven’t compared the RSPdx directly with the RSP2 yet, I do feel HF performance is substantially better than its predecessor. Indeed, in my comparisons, I often found it gave the Excalibur some serious competition. Overall, the Excalibur had an edge on the RSPdx, but the gap has closed substantially. That’s saying something.

For the comparison videos below, I also included the excellent AirSpy HF+ Discovery.

40M LSB – RSPdx vs. HF+ Discovery:

80M USB – RSPdx vs. Excalibur:

31M Broadcast – RSPdx vs. HF+ Discovery:

As you can see and hear, the RSPdx is now in the league of some of the finest HF receivers in my arsenal.

But I’m curious to know what you think after listening to these comparisons. Please comment!

Notch Filters

For those of you living in areas with DAB/DAB+ broadcasters nearby, you’ll be happy to note that the RSPdx has a DAB filter to help mitigate any potential overloading.

Also, if you live near a blowtorch mediumwave station, you’ll be quite pleased with the MW notch filter. It’s so effective at filtering out the mediumwave band, my local blowtorch on 1010 kHz is barely visible on the spectrum once the notch filter is engaged. (Note: I should add that neither the DAB nor the mediumwave notch filter was engaged during any of my previous comparisons above.) Check out the screen shots below showing the mediumwave band before and after the MW notch filter is engaged:

Before:

After:

Summary

For those of you looking for a budget wideband SDR with solid performance below 30MHz, look no further.

For $199 US, you’re getting a quality UK-designed and manufactured SDR in a proper metal housing.  The OEM application, SDRuno, is one of my favorite SDR applications and can fully take advantage of the RSPdx’s new HDR mode. No doubt, with a little more time, most third-party SDR applications will also support the RSPdx.

Frankly, I was expecting classy mediumwave and longwave performance as this was the most touted upgrade of the RSPdx. SDRplay certainly delivered.

In my experience, SDRplay doesn’t oversell their products. Their preliminary product sheet mentioned improved performance on HF, but their press release didn’t even mention the HF upgrades. And this is where I, in particular, noticed significant improvement. Perhaps this is because I am primarily an SWLer, thus spend a larger portion of my time in the HF region.

SDRplay products also have a mature, robust SDR application via SDRuno. Day to day, I tend to use Simon Brown’s SDR Console as my primary SDR application, since it’s compatible with so many of my SDRs and also offers some of the best recording functionality for those of us who do audio and spectrum archiving. Each time I beta test or review an SDRplay SDR, however, I’m more and more impressed with SDRuno. It’s evolved from being a rather cluttered application to one with a thoughtful, cohesive user interface that’s a joy to use––a product of true iterative agility.

Indeed, after having used SDRuno exclusively these past two weeks, I believe I would consider it as my primary SDR application…if only it had audio recording in addition to spectrum recording, and could run multiple instances with multiple SDRs. Again, given a little time, I wouldn’t be surprised if some of this functionality is eventually integrated.

Questions?

Since many SWLing Post readers already own an SDR, I’m sure some of you will have questions. Let’s address a few of those right now.

Question: “I have an RSP2/RSP2pro. Should I upgrade to the RSPdx?”

My recommendation: If you are a shortwave, mediumwave, or longwave DXer, I would indeed recommend upgrading to the RSPdx. If you primarily use your RSP2 series SDR on frequencies above 30 MHz and only occasionally venture below for casual listening, then I’d keep the RSP2.

Question: “I have an RSP1a. Should I upgrade to the RSPdx?”

My recommendation: If you’ve been enjoying your RSP1a and would like to take your listening/monitoring to the next level, then, yes, I would upgrade. Not only can you take advantage of the RSPdx’s enhanced performance, but the RSPdx affords you three antenna ports, and has a more robust front end.

Question: “I have an RSPduo. Should I buy the RSPdx?”

My recommendation: I’m a big fan of the RSPduo. Unless you’re a dedicated mediumwave/longwave DXer, or you’d just like to add another separate SDR to your radio arsenal, I wouldn’t rush out to buy the RSPdx.

And while I’m offering advice, I’d like to offer my standard two cents on the subject of performance optimization: a radio is only as good as its antenna! If you have a compromised antenna, invest in your antenna before upgrading your radio. You’ll be glad you did.

Conclusion

Happily, I can  recommend the SDRplay RSPdx without hesitation. This latest iteration of the RSP series SDR is a proper step forward in terms of performance and functionality––obviously implementing years of customer feedback.

SDRplay also has a proven track record of innovation and customer support. Their documentation, video tutorials, and community are among the best in the industry. Purchase with confidence.

Click here to check out the RSPdx at SDRplay.


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SDRplay announces the launch of the RSPdx

(Source: SDRplay)

SDRplay Limited has announced the launch of a new Software Defined Radio product – the RSPdx.

The RSPdx is a replacement for the highly successful RSP2 and RSP2pro SDR receivers, which have been extensively redesigned to provide enhanced performance with additional and improved pre-selection filters, improved intermodulation performance, the addition of a user selectable DAB notch filter and more software selectable attenuation steps . The RSPdx , when used in conjunction with SDRplay’s own SDRuno software, introduces a special HDR (High Dynamic Range) mode for reception within selected bands below 2MHz. HDR mode delivers improved intermodulation performance and fewer spurious responses for those challenging bands.

The SDRplay RSPdx is a single-tuner wideband full featured 14-bit SDR which covers the entire RF spectrum from 1kHz to 2GHz giving up to 10MHz of spectrum visibility. It contains three antenna ports, two of which use SMA connectors and operate across the full 1 kHz to 2 GHz range and the third uses a BNC connector which operates up to 200MHz.

The RSPdx also features a 24 MHz ‘plug and play’ reference clock input which allows the unit to be synchronised to an external reference clock such as a GPS disciplined oscillator (GPSDO)
Due to its exceptional combination of performance and price, the RSP family of receivers have become very popular, and the RSPdx builds on the learning and feedback from many thousands of users across the amateur, scientific, educational and industrial SDR community.
As was the case for the other RSP family members, SDRplay will work with developers of the popular third party SDR receiver software packages to maximise compatibility. SDRplay will also provide multiplatform driver and API support which includes Windows, Linux, Mac, Android and Raspberry Pi 3 and 4.

The RSPdx will be available to purchase in the next few weeks and is expected to retail at approximately £159 GBP or $199 USD (excluding taxes).

For more information visit the SDRplay website on www.sdrplay.com 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

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Guest Post: Decoding WEFAX using an RSP SDR and SDRuno

Many thanks to SWLing Post contributor, Mike Ladd with SDRplay, who shares the following guest post:


Basics to decoding WEFAX using an RSP and SDRuno

by Mike Ladd

SDR I use:
RSPduo from SDRplay using the Hi-Z input. Any model RSP’s can tune WEFAX transmissions. https://www.sdrplay.com/rspduo/

Antenna I use: Megaloop FX from Bonito. In an Inverted delta loop configuration pointed N/E-S/W. Any good antenna placed outdoors should be fine. It’s all about the SNR, not your S-meter reading. https://www.bonito.net/hamradio/en/mega-loop-fx/

Software:

SDRuno v1.32
SDRuno is an advanced Software Defined Radio application platform which is optimized for use with SDRplay’s range of Radio Spectrum Processing receivers.
https://www.sdrplay.com/downloads/

VBcable (donationware) vPack43
Transfers audio, digitally from one application (SDRuno) to another (Black Cat HF weather Fax) with zero loss.
https://www.vb-audio.com/Cable/

VAC (paid for use) v4.60
Transfers audio, digitally from one application (SDRuno) to another (Black Cat HF weather Fax) with zero loss.
https://vac.muzychenko.net/en/
https://www.sdrplay.com/docs/SDRuno_VAC.pdf

Black Cat HF Weather Fax (paid for use) beta 19
Decodes and produces images from the WEFAX transmissions from the output of SDRuno using a virtual audio cable.

Use the discount link available here
http://blackcatsystems.com/register/black_cat_hf_weather_fax_sdrplay_promo.html
https://www.blackcatsystems.com/software/hf_weather_fax.html

Black Cat Uno UDP
UnoUDP allows you control SDRuno’s VFO frequency from within Black Cat HF Weather Fax scheduler. This is done over a virtual com port pair using a virtual com port emulator. http://blackcatsystems.com/download/UnoUDP.zip

VSPE or COM0COM
VSPE is a paid for use app. COM0COM is completely free. Either one of these applications will work. A virtual com port emulator allows you to create a virtual com port. The pair will internally link Black Cat Weather Fax decoder to SDRuno’s using UnoUDP as the transport protocol.

VSPE http://www.eterlogic.com/Products.VSPE.html
https://www.sdrplay.com/docs/SDRuno_VSPE.pdf

COM0COM http://com0com.sourceforge.net/
https://youtu.be/dZg7puQ9Ajk

Introduction:

(some text taken and edited from various website)

This document is not a definitive guide to the WEFAX protocol, the process of decoding WEFAX images or reading a synoptic weather chart https://youtu.be/kzfNSvQREu8. This is only a collection of information that I have found scatter throughout the internet and re-compiled into a document, this document. Expect typographical mistakes, inaccuracies, or omissions.

WEFAX is an analog mode for transmitting monochrome images. It was the predecessor to slow-scan television (SSTV). Prior to the advent of the commercial telephone line “fax” machine, it was known, more traditionally, by the term “radio facsimile”.

Facsimile machines were used in the 1950s to transmit weather charts across the United States via land-lines first and then internationally via HF radio. Radio transmission of weather charts provides an enormous amount of flexibility to marine and aviation users for they now have the latest weather information and forecasts at their fingertips to use in the planning of voyages.

Radio fax relies on facsimile technology where printed information is scanned line by line and encoded into an electrical signal which can then be transmitted via physical line or radio waves to remote locations. Since the amount of information transmitted per unit time is directly proportional to the bandwidth available, then the speed at which a weather chart can be transmitted will vary depending on the quality of the media used for the transmission.

Radio fax data is available from the web on sites such as the ones hosted by the National Oceanic and Atmospheric Administration (NOAA). https://tgftp.nws.noaa.gov/fax/marine.shtml Radio fax transmissions are also broadcasted by NOAA from multiple sites in the country at regular daily schedules https://www.nws.noaa.gov/os/marine/rfax.pdf. Radio weather fax transmissions are particularly useful to shipping, where there are limited facilities for accessing the Internet.

Black Cat HF Weather Fax is a program that decodes WEFAX (Weatherfax, HF-FAX, Radiofax, and Weather Facsimile) transmissions sent from fixed locations around the globe.

A fax is transmitted line by line, typically at a rate of 120 lines per minute, or half a second per line. For example, to send a weather chart, you would start in the upper left corner. You would send the value of that pixel (dot), black, white, or perhaps a shade of gray. Then you would move over one pixel to the right, and send that pixel, and so on, until you reach the edge of the chart. Then you’d move all the way back to the left edge, and move down slightly, one line, and repeat the process.

Each pixel is converted into a certain audio frequency or tone. By convention, a tone of 1500 Hz represents black, 2300 Hz represents white, and frequencies in-between represent shades of gray. So if you listen to a fax transmission, you’ll hear the different tones as each pixel is present. For example, listen to a chart with mostly white background being sent. You’ll hear mostly the high pitch 2300 Hz, and some lower (1500 Hz) blips as each black pixel is sent. When a horizontal line is sent, you’ll hear a long half second burst of 1500 Hz, since the line is all black.

The transmitting station frequency modulates the carrier. That is, when a black pixel is transmitted, the carrier shifts down 400 Hz. When a white pixel is transmitted, the carrier shifts up 400 Hz. For a medium gray pixel, it stays on the assigned frequency. This is how most fax transmissions are made. Since we’re tuning it in SSB, it sounds to us as if the station is transmitting a variable frequency audio tone. The two processes are identical. This accounts for the confusion regarding what frequency to tune the radio to in order to properly decode the fax transmission. Different stations list their frequency in different ways. It is important to remember that a black pixel produces a 1500 Hz tone, and a white pixel produces a 2300 Hz tone within the AUX SP.

The setup works as follows. SDRuno demodulates the received signal. The demodulated audio is piped from SDRuno using virtual audio cable and sends it to the HF weather fax decoder. HF weather fax decoder receives this audio from the virtual audio cable that was demodulated from SDRuno and processes it, producing a picture on the screen

HF weather fax decoder can also set the VFO (tune) frequency of the RSP in SDRuno. This is done over the virtual com port pair using the UnoUDP application as the transport.

SDRuno can internally emulate a Kenwood TS-480, UnoUDP sends the Kenwood TS-480 serial commands via UDP over the virtual com port pair in order to set the frequency selected from the HF Weather Fax Scheduler option over to SDRuno.

You will need to install and configure the following applications.

1: A virtual audio cable.

2: A virtual com port emulator (If you would like HF Weather fax to communicate with SDRuno).

3: UnoUDP (If you would like HF Weather fax to communicate with SDRuno using the virtual serial emulator).

4: HF Weather Fax.

5: A simple wire antenna placed outdoors.

Virtual Audio Cable:

A virtual audio cable allows you to pipe the audio from one application (SDRuno) into another application (a decoder like HF Weather Fax) digitally. I will assume SDRuno is already installed with your device attached and functioning properly.

You can now download a virtual audio cable package.  If you already have a virtual audio cable package installed, you can skip to the next section. If you don’t have a virtual audio cable application installed, you only need to choose one and install only one of the two that are available.

Close any running apps, install the virtual audio cable and reboot your computer. When your computer boots to your desktop, your computer will now have a virtual audio cable pair installed on the system.

You can verify it the installation by going to your Control Panel and double clicking the Sound icon. VB-Cable and Virtual Audio Cable will only install a single virtual audio cable pair, one is for the input (Recording) and one is for the output (Playback). A single pair is all that is needed (as shown below).

Virtual Serial Port:

A virtual com port emulator is only needed if you would like Black Cat HF Fax decoder the ability to tune the station in SDRuno when you double click a station name in the HF Fax Decoder scheduler.

Please use the links provided (additional PDF’s and YouTube videos) on Page 2 of this document for an installation / configuration walkthrough.

You can download my WEFAX frequency bank for use in SDRuno below should you choose not to use a virtual com port emulator. https://signalsacrossthepond.com/download/mike-kd2kog-sdrplay-complete/

Download Black Cat HF Weather Fax and UnoUDP:

Download the latest HF Weather Fax beta package and the UnoUDP application from the link provided on Page 2 of this document. I suggest making one main folder called HFfax and two subfolders within HFfax for each of the applications. One folder is for the HF Weather Fax Decoder and the other folder is for the UNO UDP transport application.

Double click the HF Weather Fax beta ZIP file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “Black Cat Weather Fax” EXE file and send a shortcut to your Desktop.

Double click the UnoUDP zip file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “UnoUDP” EXE file and send a shortcut to your Desktop.

You should have two shortcuts on your desktop, One for the decoder and one for the transport app.

Black Cat UnoUDP:

HF Weather Fax needs a way to communicate with SDRuno, this is done via UnoUDP and the virtual com port emulator.

Launch UnoUDP with the above configuration. Set your UDP Receive port to 58084 and your UDP send port to 58083. UnoUDP must be left running in the background, this will control SDRuno. You can minimize the application or right click the shortcut and have UnoUDP auto minizine on launch.

You should see a Firewall popup prompt asking permission to allow UnoUDP to pass data within the system. You must allow this traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.

Assign 1 of the 2 com ports from the virtual com port emulator to UnoUDP (the 2nd com port will be assigned to SDRuno).  My com port pair is Com 1 and Com 2, SDRuno uses Com1 and UnoUDP uses Com 2.

Black Cat HF Weather Fax:

HF Weather Fax needs to be configured in order to communicate with UnoUDP, this is done via the UDP settings. Click “Edit” and “Preferences” Set the UDP Send port to 58084 and the UDP Receive port to 58083.

You should see a Firewall popup prompt asking permission for HF Weather Fax to pass data within your system. You must allow UDP traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.

SDRuno:

SDRuno needs its Output assigned to the Virtual Audio Cable. The output can be changed via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.

SDRuno needs a com port assigned so it can be externally controlled. The serial port is assigned via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the CAT tab.

I recommend running the RSP in LOW-IF mode, this is selected via the MAIN panel. This reduces the need to track separation between the Tuned frequency and LO (local oscillator) https://youtu.be/Fsns4P3JxrM

LOW-IF mode also minizines the LO being placed outside of the desired preselect filter of the device in use, Remember the preselect filter is automatically enabled based on the LO frequency https://youtu.be/w-vkiVp7Q4E

I also recommend leaving the IF AGC enabled and placing the RF GAIN as high as possible without causing an ADC OVERLOAD warning within the MAIN panel. If an ADC OVERLOAD warning appears, back the RF GAIN down.

https://www.sdrplay.com/wp-content/uploads/2018/06/Gain_and_AGC_in_SDRuno.pdf

Your first WEFAX decode (Using UnoUDP)

Launch UnoUDP and minimize it.

Launch Black Cat HF Weather FAX.

Launch SDRuno. Set the mode to USB and the filter width to 2.8k
HF weather fax will not set the mode or filter width at this time.

Click the Sked button in Black Systems HF Weather Fax. A current WEFAX transmission schedule will appear. Stations listed in White are either scheduled to transmit or about to transmit based on your computers clock. Stations show in Grey at the bottom of the list are currently off the air or not transmitting.

In the Freq Offset: box enter -1.9 and hit enter (Reason for this is on Page 5).

Click any of the stations listed in the Fax Transmission Schedule and it will automatically tune SDRuno to the correct frequency.

Black Cat HF Weather Fax folder will have a file named “Black Cat HF Weather Fax Docs” Please view this file to understand some of the advanced features available.

Your first decode (Without UnoUDP)

Launch Black Cat HF Weather FAX.

Launch SDRuno.

Navigate to the Memory Panel (MAIN panel and click the MEM PAN button)

Right click the Memory panel and select “Open bank”. Navigate you C drive telling SDRuno the location of WEFAX.s1b

Double click any of the frequencies shown within the WEFAX bank and SDRuno will set the correct mode and tune that station.  My WEFAX.s1b file defaults to the Hi-Z port. If your device lacks a HI-Z input, navigate to the port section within the memory panel, double click the stations port you want to edit and change it to the correct port that’s available or in use for your device. Right click the memory panel and “Save bank” to save the changes.

To use my SDRuno WEFAX frequency bank properly. The MCTR button must be enabled within the RX CONTROL panel, enabling this option allows you to double click and tune a station that is stored within the WEFAX bank. Make sure the LO is not locked in the MAIN panel (LO LOCK).

If a decoded WEFAX image looks blocky or skewed or possibly pixeled, I recommend that the lock output fractional resampler option is enabled in SDRuno. You can enable this from the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.

I hope this document helped guide you in getting started with decoding WEFAX transmissions from around the world. I am sure I missed some key features, remember this is only a primer/basics to decoding WEFAX. I do have an accompanying video located here

https://youtu.be/vAYGVimzNX8

Warmest of 73,
Mike-KD2KOG

Disclaimers

SDRPlay modules use a Mirics chipset and software. The information supplied hereunder is provided to you by SDRPlay under license from Mirics. Mirics hereby grants you a perpetual, worldwide, royalty free license to use the information herein for the purpose of designing software that utilizes SDRPlay modules, under the following conditions:

There are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. Mirics reserves the right to make changes without further notice to any of its products. Mirics makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Mirics assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters that may be provided in Mirics data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters must be validated for each customer application by the buyer’s technical experts. SDRPlay and Mirics products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Mirics product could create a situation where personal injury or death may occur. Should Buyer purchase or use SDRPlay or Mirics products for any such unintended or unauthorized application, Buyer shall indemnify and hold both SDRPlay and Mirics and their officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that either SDRPlay or Mirics were negligent regarding the design or manufacture of the part. Mirics FlexiRFTM, Mirics FlexiTVTM and MiricsTM are trademarks of Mirics .

SDRPlay is the trading name of SDRPlay Limited a company registered in England # 09035244.

Mirics is the trading name of Mirics Limited a company registered in England # 05046393


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Last call for SDRplay RSP/RSP1a metal cases

Many thanks to Mike Ladd of SDRplay who shared the following note on the SDRplay Facebook page:

Just a heads up. The RSP1/RSP1a metal case upgrade are almost all gone. I will not be re-releasing this case. Grab them now while you can.

Click here to purchase on eBay.

Click here to view on Amazon (affiliate link).

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Mike’s expanding collection of SDRplay tutorial videos

Besides making great receivers, one of the things I love about SDRplay is their focus on providing user documentation and tutorials. We’ve mentioned before that SDRplay’s Mike Ladd (KD2KOG) actively creates tutorial videos exploring a number of SDRplay topics. To date, he’s produced over 20 videos–!

If you own an SDRplay product, I’d strongly recommend checking out Mike’s video list even if you feel you’re already a pro user. The videos are easy to follow and are chock-full of SDRuno tips and tricks.

I’ve pasted the latest links to the Mike’s videos below but I would encourage you to check the SDRplay YouTube channel (link below) and this page for the latest episodes as they are regularly updated.

From the SDRplay Ham Guides page:

As SDRplay RSPs get used for more and more receiver applications, we felt we didn’t want to lose sight of the large number of people who love short wave listening and HF ham radio, so we have created “Ham Guides” as a place where we focus on providing tuition and help for all aspects of receiving radio signals at 30MHz and below. This includes set up and use of SDRuno, and tips and techniques on key related topics such as decoding, propagation and antennas.

The SDRplay Ham Guides YouTube channel can be found here, at  www.youtube.com/c/SDRplayHamGuides 

SDRplay Ham Guides complements the main SDRplay YouTube channel and all the documentation available via https://www.sdrplay.com/downloads/and the searchable resources in our Applications and Support Catalogue: https://www.sdrplay.com/apps-catalogue/

If you have ideas for what you’d like to see more of, then add your comments to the videos or email me at [email protected]

  1. This is the first video of many to follow. Showing basic operation of SDRuno using a RSP1a SDR.https://youtu.be/ngv60EWiJ3U
  2. Minimum requirements for running SDRuno.https://youtu.be/Rn3tuiIOvmM
  3. Virtual audio cable basics in SDRuno.https://youtu.be/ZF86cK5vukY
  4. Shaping the sound of shortwave broadcast stations using SDRuno.https://youtu.be/smvfCGx6zO8
  5. Using SDRuno’s built in software notch filters.https://youtu.be/5K92dG2sedw
  6. SDRuno basics, MultiPSKhttps://youtu.be/tnqfJhsvGFA
  7. SDRuno basics, Import the free EiBi HF databasehttps://youtu.be/ZJlfxaudaNI
  8. SDRuno basics, The EX CONTROL panel part 1.https://youtu.be/1XdBqXcyuzw
  9. SDRuno basics, The EX CONTROL panel part 2.https://youtu.be/H0RJVy4u5Ro
  10. SDRuno basics, My HF frequency lists part 1.https://youtu.be/KiNjsvKHVeU
  11. SDRuno basics, My HF frequency lists part 2.https://youtu.be/Rx3B-6h_CIw
  12. SDRuno basic, Decoding WEFAX using Black Cat HF Weather Fax decoder.https://youtu.be/juTdBpTDVp0
  13. SDRuno basics, Removing wide band noise.https://youtu.be/_GtozskwFAY
  14. SDRuno basics, CSV user list browser.https://youtu.be/1vu5fAjdRHw
  15. SDRuno basics, RSPduo, dual tuner mode, listening and decoding signalshttps://youtu.be/1vu5fAjdRHw
  16. SDRuno basic, VRX-Virtual receivershttps://youtu.be/ndUPm6Nccb8
  17. Why I chose a loop.https://youtu.be/XesvzZG-Mi8
  18. SDRuno basics, decoding CTCSS/DCS toneshttps://youtu.be/PM3WOMF7_eM
  19. SDRplay user support options and resourceshttps://youtu.be/nXnrBaoKKjs
  20. RSRduo with dual W6LVP loops Part 1https://youtu.be/w5SrDtUxhQU
  21. RSRduo with dual W6LVP loops Part 2https://youtu.be/ikUymHFkCcY
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