Well I was poking around the linux repos looking for a program that I can use as a tone generator for some of my electronics projects when I stumbled upon this wonderful program: http://www.baudline.com/
This little program not only has a tone generator with noise and sweep capabilities but its a handy little tool to do fourier analysis and general spectral analysis. The program is currently only avalible for *nix based machines but the source is provided so I am sure a windows compile can be done (provided the sound API is standard…)
Check out this interesting screenshot:
Thats one crazy complex signal to create the matrix scrolling letters effect! Those HAM radio events can get crazy. To step it up a notch somebody put out a QR-Code (A 3D UPC) over the radio waves:
Anyways Baudline is a great program so far however their is a few issues to note. If you are using a standard distro such as Mint or Ubuntu then you will not be running the required Jack audio daemon that baudline requires to have access to the sound hardware. Their are how-to’s on the web but they all require much more work than a simple little init script can provide and they do not require system changes! I will post my script in the next post. Once you get things up and running one thing to note is that you can not play back anything with stdout in the output devices window or you will crash. You also can not record from Jack unless you actually have an input source or baudline will crash. Their are still some bugs but their easy enough to work around.
Basic usage info:
To run Baudline you need to start it via the command line or else you will not have any input or output devices in the selection windows. To run with all options enabled like I do run this command
./baudline_jack -stdin -stdout
That simple command will let you pipe files in from the command line (such as from an audio recording) this is also mandatory if you wish to use the tone generator as by default it can not output directly to the Jack output device. You must first select stdout in the tone generator window and then record the signal then play it back via Jack. Its not actually a big deal as 99% of the time you want to make sure what signal you’r going to output is correct first.
Here is a screenshot of my setup: