AirSpy One ExtIO for HDSDR see http://hdsdr.de/ see http://airspy.com/ * Input Samplerate from device to HDSDR can be changed using HDSDR's "Bandwidth [F6]" menu. This can be switched between 2.5 and 10.0 MSPS. 10 MSPS requires a very fast PC and especially USB transfer. You might need to slow down to 2.5 MSPS in case of overload and stuttering! In SDR# (see http://sdrsharp.com/ ) this option is called "Device sample rate". * Bias T of +4.5V @ 50 mA is controlled with HDSDR's IF slider - IF+0: Bias T is always off - IF+0 (highlighted): Bias T is always on * LNA/Mixer/VGA gain is controlled in combination with HDSDR's "RF" slider The value on the RF slider shows some value, which is a hint. For sure, it will not be exact! You see positive values (>0; e.g. RF+4) when dynamic range (blocking range) of AirSpy is limited. "RF+0" corresponds to LNA 14, Mixer Gain 12 and VGA 5 in SDR#. Range for the RF slider is -58 .. +34 dB: a range of 92 dB. * Automatic Gain Control (AGC) for LNA and Mixer is NOT controlled, because you would always need to adjust (at least) VGA! This ExtIO is developed using - libairspy https://github.com/airspy/host - libusb http://sourceforge.net/projects/libusb/files/libusb-1.0/libusb-1.0.19/libusb-1.0.19.7z/download - pthreads and Visual Studio (C++) Express 2013 for Windows Desktop Send your requests/comments to LightCoder