Binaural CW Receiver with GNU Radio and USRP

Today I felt like doing an experiment that is not quite on my TODO list – a binaural CW receiver. A binaural CW receiver is a receiver that gives a spatial feeling while you are tuning. As I understand it, you have to use stereo where the signals move from one side to the other as you tune and are in the middle when you are tuned to the frequency.

Read more

Improved AGC for the simple SSB receiver

Few days ago I wrote about how I upgraded the simple double side band receiver implemented in the GNU Radio Companion to a simple single side band receiver. This initial implementation used some default values for the AGC attack and decay rates. These values were acceptable; however, I wanted to spend some time trying to find better values that would correspond to Fast, Medium and Slow AGC – just as we are used to in commercial radios.

Read more

Simple SSB Receiver in GNU Radio Companion

The simple SSB software defined radio receiver is now functional!

Few days ago I wrote about how to upgrade the simple double side band receiver to single side band. The modification was supposed to be very simple and involved changing the band pass filter from using real taps to use complex taps. The upgrade wasn’t quite as easy, though.

Read more

From double side band to single side band reception

Simple CW receiver 0.3When I presented the Simple CW Receiver few weeks ago I also mentioned and demonstrated that it is actually a double side band receiver (it’s around 2:35 in the video). This is good for AM and FM, but can be very inconvenient for receiving CW and SSB (single side band). If the station we are trying to receive is surrounded by other stations on the neighbouring channels, these will interfere via the opposite side band. Therefore, it was time to look into single side band reception.

Read more

OZ7IGY beacon with GNU Radio, USRP and WBX

I was playing with GNU Radio, the USRP and the WBX daughterboard tonight preparing for the tests of the 5.7/5.8 GHz receiver setup tomorrow. For some reason that I can not remember, I have decided to tune in to 432.471 MHz – the UHF frequency of the OZ7IGY beacon, which is located approximately 50 km … Read more

Simple CW Receiver with GNU Radio

I have been playing with GNU Radio and GRC (GNU Radio Companion) over the weekend and I ended up implementing a very simple CW receiver. This will be very handy on Tuesday when we will be testing the 5.8 GHz UNITEC-1 setup for the first time using the OZ7IGY beacon on 5.76093 GHz. Here is a quick video demo of the receiver where I use my Yaesu FT-817ND to transmit a test signal.

Read more