Browsing all articles tagged with Software defined Radio

A few weeks ago (I’ve been meaning to do this post for ages, few weeks ago is give or take 2 months) there was a post on reddit regarding a new software defined radio that cost around $20. After reading a few topics on the discussion (now all avail at http://www.reddit.com/r/RTLSDR now http://rtlsdr.reddit.com) my interest was peaked. RF was a whole new world of WTF for me. I think it offers the same awe and wonder that I had putting a tape into my very first tape into my vomit brown fischer-price tape player:

The basic gist of how it all works is as follows:

* There is a common chip found in video cards known as an RTL2832U
* This chip is commonly used for specific frequencies used for Television signals (and then software decodes this so you could watch TV on your pc)
* A bunch of cool guys ™ found a way to read the data coming into the card directly with drivers
* These cards also offered some tuners that allowed tuning beyond the basic TV ranges

So there are 2 basic sections:
* RTL2832U chips – reading data
* Tuner (E4K,other) – allows changing frequencies to various ranges

With such I started hunting around in Centurion for a Video card that had these options, after phoning a few places (read 5/6) I eventually found a TV card known as a Compro VisionMate U650F. It costs around R250 from pcpalace in centurion which offers a RTL2832U as well as the E4K tuner (the best one at this stage). *update* the cheaper visionmates (without remote) go for about R100 less than this!

This meant:

* I can tune to frequencies from around 55MHz to 1800Mhz
* For R250!

This was super, ordered my card and a few days later it arrived!

Following some _really_ easy guides for installing a few tools in windows:
* HDSDR, WRPlus, ExtIO, zadig ( http://spench.net/ has all the info but at time of writing was having some issues, try one of these: http://rtlsdr.org/ http://rtlsdr.reddit.com)

And on linux:
* GnuRadio (install guide: http://gnuradio.org/redmine/projects/gnuradio/wiki/InstallingGR)
* gr-osmodr
* rtl-sdr

Off the bat I loaded up HDSDR (after all the config and setup – zadig for drivers, extIO copied) and immediately got that sinking feeling of ‘I know absolutely nothing’:

Read more »