Entering in the world of SDR
According to Wikpedia: a Software Defined Radio (SDR) system is a radio communication system where components that have been typically implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded computing devices.
Traditionally aquiring an SDR system would set you back somewhere between $2.500 and $15.000, however, in the last couple of years, many new and cheap devices have entered the market for much lower prices. The most well known are Perseus, RFSpace, et. and if you like to build one yourself there is Softrock (among many others).
Now, that’s all nice, but i wanted to do something different. You can buy anything, but what about experimenting a little and see what you can get with minimal cost and effort?
Recently Balint Seeber and his friends discovered a way to use a $20 DVB-T adapter as SDR receiver. Balint built a code-block for GNU Radio for it and with the proper drivers you can make common software like HDSDR or WRplus to work with the adapter as well. They call is RTL-SDR based on the RTL2832U chip in the DVB-T dongles.
To get everything working looks much more difficult than it really is. What you need to do is download a specific driver for the dongle and configure it correctly and then you are ready to go. I just followed the instructions from this website and got things working in the first attempt. Something highly unusual for me.
So all in all, now i have an ultra cheap SDR installation that covers 54.6MHz – 1.9GHz. I hooked it up to a $12 2m antenna and all is working fine so far. Now let the hunting for signals start. A whole new world has opened up for me.
Next thing…. Decent speakers for the laptop….