The "fax" plugin for SDRuno is a plugin for decoding weatherfax signals transmitted on shortwave
The weatherfax signal has a width of less than 1 KHz, since the minimum width of the samplerate from SDR devices is 2 MHz, there is some decimation required.
In this version, the plugin uses the SP1 stream, a data stream of 192 KHz, provided for by the SDRuno platform.
It seems wide though to use the zooming facility of the main spectrum widget to make the signal visible, a "shadow" band will show in which the signal of interest can be found.
The SP exit is selected by the plugin!
The plugin itself can be stored in the folder for community plugins (in my system "..\Documents\CommunityPlugins".
The plugin is - as other plugins - developed under MSVC. Its functioning depends on lots of other "dll's" (Dynamic Load Libraries);
If a 0x000012f error is encountered on trying to load the plugin, it means that dll's from the Visual C++ Redistributable(VS 2015) are not found.
Installing seems to be quite simple
How do I fix the api-ms-win-crt-runtime-l1-1-0. dll missing error?
Install the software via Windows Update.
Download Visual C++ Redistributable for Visual Studio 2015 from Microsoft directly.
Install or Repair the Visual C++ Redistributable for Visual Studio 2015 on your computer.
From a functional point of view, the difference between Version 2 and the previous versions is that now all settings are recorded and kept between invocations of the plugin.
Internally, there are quite some changes, mainly to improve the readability of the code.
Even in this time of internet and satelites, shortwave ansmissions are still used to transmit weathercharts. The picture shows a (noisy) signal, 4610 KHz, with the weatherfax plugin.
The frequencies on which weathercharts are transmitted are to be found in e.g.
https://www.weather.gov/media/marine/rfax.pdf
Most transmissions are preceded by a signal 400 Hz higher than the official carrier frequency, a transmissions starts with a signal of 300 Hz (Phase modulated) during a few seconds.
The implementation of the plugin is a reimplementation of the wfax decoder of the swradio-8 implementation, that decoder was reimplemented as well.