Archive for June, 2011

ROS with SoftRock SDR

28 June, 2011

Now ROS can operate directly with some SDR kits, like SoftRock, KTH, PM, Zeta SDR, G4JNT LF Upconverter…. (ask me for inlude new SDR kits)

In Rig Menu, click on SDR if you are using some of these kits.  I/Q processing will be activated automatically.  You need to have  Stereo input or output (Usually, Mic input is mono).

Adjust the I/Q balance using the Phase, Gain and Delay sliders. Configuration is stored for each band. Click on Fine for a Fine Adjust.

If the SDR if shifted in frequency you can use the Offset Slider for a Fine Frequency Adjust too.

For Zeta SDR you have to to enter the LO frequency. 14.318/4 is ideal for using ROS on 80 meters band.

The G4JNT LF UpConverter was tested by his author, Andy Talbot, using the Soundmax Internal Soundcard getting 60dB of image rejection for the ROS MF Mode (137 and 500 Khz USB)

For monitoring the I/Q audio proccessed while you are decoding, click on Monitor. The Monitor audio filter is 300-2700 Hz.

Specials thanks to Dave 2E0DPQ for a lot of test with softRock between England and Spain. He got a complete communication with Argentina on 20 meters with 1 watt and ROS.

Also special thanks to KB9YIG for the Softrock TX/RX kit, and PE0FKO, PA0RWE and IW3AUT for the Si570 support, and  G4JNT for the TX I/Q adjustement test.