This weekend I have been playing with a full duplex transceiver version of the simple DVB setup that allows to use only one computer and one USRP as a transmitter and receiver. By using separate daughterboards I can use one side to transmit and the other side to receive. Using two sets and two frequencies the transceiver can be used for two-way video conferencing over the air 🙂
transceiver
WBX receiver sensitivity in CW
After finishing the initial “smoke tests” on the 5.6-5.9 GHz receiver setup – in particular the KU LNC 5659 C PRO down converter, we decided to measure the sensitivity of the WBX receiver over the whole range. We define sensitivity in this respect as the weakest CW signal that: Gives an SNR of at least … 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
The WBX as full duplex VHF/UHF amateur radio satellite transceiver
One of the reasons I have been very excited to get the WBX transceiver daughterboard for the USRP is that with one single RF board I can have a full duplex transceiver covering both the 2 m and 70 cm amateur radio bands. This is where most of the amateur radio satellite traffic takes place, … Read more
WBX Transceiver Tests using GNU Radio and USRP
This video shows my first on-the-air tests with the WBX transceiver using the USRP (Universal Software Radio Peripheral) and GNU Radio.
The receiver was tested using wide band FM broadcast, APT signal from NOAA 17 satellite and Copenhagen VOLMET. I have also performed some tests using DVB-T signal and wireless sensor signals but I wanted to keep the video short so these were not included. I can post them in separate videos if there is interest.
WBX receiver test on the air: Copenhagen VOLMET
I have been quite busy during the last weeks doing overtime at work, nonetheless, I have managed to carry out some small on the air tests of my newly acquired WBX transceiver boards for the USRP and GNU Radio. Tonight, I tuned in to Copenhagen VOLMET that transmits AM on 127.000 MHz.
The WBX 50-2200 MHz transceiver
It was a good day today. At long last, I have received my WBX transceiver boards for the USRP! I have been waiting for this transceiver board for quite some time now because I didn’t really have and transmit capabilities in the VHF and UHF bands. This board was expected to cover 50 MHz to … Read more
Live recording of receiver tests
Tonight I have been testing some ham radio transceiver code written in Python/GNU Radio. It is some student project published on SourceForge. You can find the code on the project page at Sourceforge: http://sourceforge.net/projects/sdr.
PBT Mod for the IC-765
As you may already know, the IC-765 has IF-shift but no passband tuning. There is, however, a simple mod originally designed by Gerd Henjes, W2ISB, which allows the IF-shift button to tune the passband while the IF-shit button is in OFF position. This mod is described in the VE3HUR IC-765 notes and reproduced here with some illustrative pictures, as well as a video demonstrating the difference between PBT and IF-shift
IC-765 Overview
The IC-765 has been ICOM’s flagship HF-radio for many years. Even today (2006) it represents excellent value for money as it has one of the best receivers ever made. The IC-765 has 4 IF stages (69MHz, 9MHz, 455kHz, 9MHz), built-in power supply (PS-35) and automatic antenna tuner (AT-150), and it comes with 500Hz CW filters (mounted from the factory. Optional 250Hz CW filters (FL101 and FL53A) are available, too, as is the optional FL102 6kHz AM filter.