Win an RTL-SDR adapter or up-converter!! (update)


And the prize goes to……. ME!!! I replaced the VAC with this one and all works as expected.


I have a puzzle for you! A new RTL-SDR adapter or up-converter for the person who gives me the solution.


Remember this setup? This is my RTL-SDR panadapter setup i am using and which i am extremely happy with. Recently i found a nice FTP server where i can download most of the digital signal decoding software on the market to try out. I only have two problems here: First of all i cannot install all the software on my laptop for various reasons and second, many software comes with a “patch” to make annoying try-me dialogs go away, if you know what i mean. And anti-virus software doesn’t really like that kind of patches. So what i do is load all that software up in a virtual machine and like that, if i screw up the VM i can roll it back to the latest snapshot.

Now here comes the problem: This software normally uses some audio input to get the signal in, in Windows a “recording device”. So what i have done is the following:

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I installed a Virtual Audio Cable and linked my soundcard (Playback Device) to it. Like this i eliminate a A/D and another D/A converter and sound quality should be identical to what comes out of the SDR device. The other side of the VAC i hook up to the VMWare virtual machines sound card. And that´s where things go stuck.

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If you look at the Sound Card config in VMWare you see that that i can only select playback devices like Speakers, Headphones and such. There is no such thing as a Microphone or Line Input. They do exist in Windows and VMWare mappes them to the WAVE_MAPPER so in theory when i select the VAC as default recording device in my VMWare host (my laptop), then Windows in VMWare guest should pick that up as default recording device. Well, guess what? It does not.

So the challenge is this: How to get the VAC recognized and working as a recording device in VMWare (or any other virtualization platform, for that matter)? A new RTL-SDR adapter or up-converter for the one who sends me the solution.

Playing around with ADS-B

Ok, this is not going to be a very interesting post. It’s just a simple to-let-you-know that i now am spotting planes using an RTL adapter connected to a raspberry pi. If you are not interested you can stop reading now.

The other day i found this website called FlightAware because i needed to check a flight from Paris to Barcelona in which a friend of my wife was traveling. You know, surprise at the airport, we don’t want to be too early nor too late, that kind of thing.

That’s when i read about monitoring ADS-B using the RTL adapter and a raspberry pi. I still had a pi that was destined to be for an arcade machine which i never built and after being a MAME machine and an ad-blocking DNS cache i decided to look into this ADS-B stuff.

What is this ADS-B thing anyway? Well, ADS-B is used to communicate the position of airplanes to air traffic control. A bit like this:








FlightAware has a pre-build pi image called piaware, but downloading that onto an SD card would be the easy way, so i built everything from scratch on the existing RetroPi distribution which is based on rapbian.

First i had to understand how it works. The main program here is dump1090. Dump1090 uses the RTL-SDR adapter to tune it to 1090MHz and sits there listening for incoming mode S traffic, decodes it and makes that available several formats on several TCP ports on the system you are running dump1090 on.

dump1090 has another cool feature and that is that it is able to publish the data on top of a Google Map. And that looks like this:

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Incoming traffic for LEBL

Because this all started when i went to check FlightAware i am also publishing my data to their website. In turn i got a free license for PlanePlotter, but i am not using that. So why did i build this? No idea. I just think it’s fun to have all this running.

So there you have it. If you want to know how to build it, there are several manuals out there that guide you. Or you can use the pre-build piaware distribution, but be aware, there are some differences between a standard raspbian and piaware, specifically in the startup scripts. That’s why i didn’t want to use it.


HDSDR vs. SDR-Console

Currently i am using HDSDR as my panadapter for having a glance at the band while i am working with the radio. And while HDSDR is a great piece of software we also know that HDSDR is a technical piece of software where user friendliness was not the main priority when it was developed, to say the least. It actually takes quite some time to get it configured properly and to find all the buttons and dials you can use and how to actually use them properly.

There are many other software programs out there, the most used ones being SDR#, PowerSDR and many more. Because i still am not completely used to HDSDR sometimes i start to get frustrated (specially when listening to FM wide-band radio) and start looking for other software to do what i do. My requirements are:

  • Clear and configurable waterfall and audio scope
  • CAT control either direct or through Omni-Rig
  • Ease of use
  • As many modes possible
  • Protocol decoding is a nice to have

Someone in one of the SDR Facebook groups suggested me to try out SDR-Radio V2. SDR-Radio is written by Simon Brown HB9DRV who was also the original developer of the back then great and now not so much anymore HAM Radio Deluxe software.

Looking at SDR-Radio Simon really knows what he is doing and he packs a lot of functionality into this package. From the list mentioned above it does all and more. SDR-Radio consists of three programs, the SDR-Console, SDR-Server and Data File Analyser, from which i only going to talk about the Console.

Installing is just a matter of clicking the Install executable and Next, Next, Finish. To get the RTL adapter to work you have to copy the right dll’s into the install directory and perform the Zadig fiddling as you would with every other software that doesn’t support the RTL adapters out of the box.

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When you first start the console the SDR-Console is going to ask you which SDR radio you want to use. In the Radio Definitions dialog you will find a Search option and when you did the Zadig and dll stuff right you will see an option called RTL SDR (USB). The RTL SDR (TCP) option is always there. You use this option when you want to access a remote RTL adapter. The RTL SDR (USB) option is only there if SDR-Console can accesss the RTL-SDR drivers you installed using Zadig.

03-07-2015 1.00.22 PMWhen you do a search SDR-Console will find your RTL Adapters, in my case two.

Select the adapter you want to use and press OK, select the adapter again and press Start.

SDR-Console should now begin to work for you.

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As you can see SDR-Console looks completely different from HDSDR. In the beginning i found SDR-Console to be pretty daunting to work with. There is A LOT of functionality here. Simon has kept the same framework he used for HRD which allows the user to open, move, float or dock panels wherever he wants, thus creating your own workspace with the features you need for what you are currently doing.

Things i like about SDR-Console:

  • Huge amount of functions ranging from PSK31 and RTTY decoding (very basic and those are the only protocols, unfortunately), CAT support using Omni-Rig including support for IF inputs, HF frequency database support, Satellite Tracking, FM stereo radio support, etc, etc.
  • Extensive DSP functions with several filters, noise reduction, notch , squelch, etc.
  • More modes than HDSDR including excellent FM stereo support with RDS.
  • Selectable playback devices. I have 6 output devices on my laptop…
  • Easy to use and customize interface.

Now, there is ONE thing i ABSOLUTELY don’t like about SDR-Console and that’s the way you navigate the band. I am used to point and click to select the signal i want. If you do that in SDR-Console your frequency goes everywhere. Probably it’s just me, but i lost track of many weak signals just because i saw it on the waterfall, clicked on it, forgot to remember the frequency, SDR-Console changes the frequency and i never found the signal back. If you don’t have the center frequency in the center of your screen it does the same when changing filter width or band spread by dragging the edges using the mouse. I am probably doing something wrong, but i find the HDSDR interface much more intuitive in that respect.

I find the waterfall of HDSDR more precise and more detailed. A picture says more than 1000 words.

03-07-2015 2.05.46 PMIf i03-07-2015 1.52.28 PM look at a signal on 16.148MHz in HDSDR it looks like the image on the left. If i look at the same signal (after more than 5 minutes tuning, adjusting the filter, tuning again, adjusting the filter again, again, lost the signal, where was it? Ah, 16.148. Tuning again. THIS SUCKS!!) the signal looks like the image on the right in SDR-Console. Completely different, no details on the shift, etc.


While writing this article i had to go through the “adjusting frequency because i touched the filters”-hell again. For me this really really spoins the fun of working with SDR-Console. I love the program. It has everything HDSDR is missing, but this really needs to be fixed. Unless it’s me, of course and then i would like some suggestions on how to better manage moving across the waterfall.

Until this is resolved i stick to HDSDR.