This week on the SignalsEverywhere YouTube channel, host Corrosive gives us a tutorial on common modulations that you'll see on your software defined radio. His tutorial covers Amplitude Modulation (AM), Frequency Modulation (FM), Single Side Band (SSB) and Conintuous Wave (CW) modulations. In the video he shows what they look like and how to select the correct mode and bandwidth settings in SDR#. Corrosive uses an Airspy in the video, but the same concepts are valid for any SDR, like the RTL-SDR.
If you're new to SDR then this is a great introductory video to watch and learn from.
AM FM SSB and CW | Common Modulation You'll See on SDR
The Contour Shuttle Express and Pro V2 are USB controller accessories for PCs. They consist of a knob-like wheel with multiple buttons and they are designed as a keyboard replacement for improving the productivity of video/photo editors. However, several people have found them useful for controlling software defined radio receiver programs like SDR#.
There was no wrapper available for Contours Windows SDK so I created a managed .NET wrapper around contours dll. If anyone wants to develop their own software for these devices I will happily provide them with my .NET wrapper for free as well as a demo app to instruct on its usage.
Over on YouTube user TheGazLab has uploaded a video that reviews the Airspy HF+, and also shows how to use the HF+ with SDR# and WSJT-X in order to create a FT8 monitor. The Airspy HF+ is high dynamic range HF/VHF receiver designed for DXing.
In the video TheGazLab demonstrates to us the decoding in real time, and explains the CAT control SDR# plugin that he's using. The CAT control plugin when combined with a virtual serial port driver allows the WSJT-X program to automatically tune SDR# to the FT8 frequency selected in WSJT-X.
Later in the video he also discusses the SpyServer network which allows SDR# users to connect to remote public Airspy and RTL-SDR units over the internet. He demonstrates connecting to a public server in the UK, and decoding FT8 via the remote server. The video also shows the new SpyServer interface by @zakhttp which nicely lays out the world SpyServer network on a map, making it easy to choose a desired location to listen to.
Airspy HFPlus, SDR# and WSJT-X with full CAT control decoding FT-8
Thanks to VE3NEA for letting us know about his new RTL-SDR compatible heatmap generator plugin for SDR#. To use the plugin you first need to generate some heatmap CSV data by using the rtl_power software. You can then open the CSV file in the plugin and it will generate a heatmap image. A frequency heatmap shows a wideband waterfall image of detected frequency activity.
RTL-SDR heatmap tools are nothing new, but the convenience of having it as a SDR# plugin is that you can click on the heatmap image to instantly tune to a frequency where activity was recorded during the initial rtl_power scan.
In the new version the 'Net Info' button is now functioning and it is possible to see the current calls, groups, and meta information on the current cell and neighbour cell. It also appears that it has been updated to allow for multiple SDR# TETRA decoder instances to be opened simultaneously now for wider band monitoring.
SDR# plugin developer Eddie Mac has again released a new plugin for SDR# called "SDR# Plugin Manager". This plugin is designed to make it easy to install, remove and re-order other SDR# plugins. Also included is a repository browser. This is a repository of many known SDR# plugin links which can be used to download and install a plugin with a simple click of a button.
If you are interested in programming your own plugins, Eddie also offers the following advice which he posted in our forum:
A good place to get started programming plugins is to download the express version of .NET (free for personal use) and install at least the C# pack. Then go to the Airspy website and download Youssef's zipped examples on coding plugins. While they are not documented you can use them as an example of the steps involved.
If you know a bit of c++ that is great it should be a good spring board to learn C#. In fact, you can even program simple plugins (like my tuner knob) in Visual Basic. Both C# and VB.NET compile to Common Language Run time anyway so to SDR# it's not much difference. The only caveat is that if you want to create any plugins to do processing on signals of any sort you MUST use C# as it supports the data types SDR# uses and VB does not. As well, VB does not allow unsafe code which C# can be instructed to allow.
Another great resource for learning to program plugins for SDR# is GitHUb and another great place is Andrej Mohar's website where he actually has a tutorial and an good explanation of the plugin coding process. You can find it here http://www.andrej-mohar.com/plugin-basics-for-sdr
If you would like an example of a "stencil" as you call it - a template, I would be happy to share a template in both VB and C# for you to use to start to learn. However, I would suggest begginning with C# from the start.
The basics of it is that the "plugin" is actually in interface that is called while SDR# loads. The "Plugins.xml" file tells SDR# what your dll is called and what the name of the plugin is. Once it has initialized your plugin, SDR# sharp asks the plugin for a "panel" control which contains the controls for your plugin. In also returns to you a "control" object interface that allows you to receive notifications of program value changes or to set program values. There are more complex things you can do but the basics are simple.
This is an excerpt from our book on RTL-SDR which we've decided to post given that many new users struggle to understand all the settings in SDR#.
SDR# is currently the most popular SDR program used with the RTL-SDR. It's easy to set up and use. To install SDR#, go through our Quickstart Guide. Below we explain some of the settings and displays in SDR#.
Upon opening SDR# you'll be greeted with the screen shown below. Here we have highlighted the main parts of SDR#
After opening SDR# for the first time, we suggest that you immediately remember to perform the following steps (if you don’t know what some of these steps are, continue reading further below for more information):
Increase the RF gain from zero to a higher value in the configure menu.
Reduce the range slider on the right of the SDR# window to about -70 (for RTL-SDR dongles).
Enable the “Correct IQ” setting to remove the center spike if using an R820T/R820T2, or enable “Offset Tuning” in the configure menu if using an E4000/FC0012/13.
Turn off the “Snap to grid” setting, or adjust the PPM offset accordingly.
Set the 'Mode' to the correct setting for the signal that you are listing to.