RTL-SDR as source with GNU Radio for WFM reception.

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Hi all...
This is about using the poor man's SDR dongle ( RTL2832U ) with GNU Radio to receive Commercial FM stations ( Wideband FM stations)...

Installation of GNU Radio was a breeze in Ubuntu 12.04 using the build script by Marcus Leech.. thank to him... My core 2 duo machine took 2 hours to build the whole thing... :)

Being a total noob in the complex base-band world, i decided to try something for getting familiarized with GNU Radio..
Opened gnuradio-companion..
Tried out some examples. Most of them were based on USRP SDR Transceiver.

But the source block listed the support of RT2832U to be used as a source.. thanks to osmocom.
So now i decided to create a WFM receiver in GNU Radio with IQ signals collecting from poor man's receiver.

Hooked the SDR dongle.. checked with some similar implementations over internet.. Created a LPF, WFM receive block, GUI Waterfall Sink block, Audio Sink block. Spend a considerable amount of time in understanding all parameters and dependencies between blocks.. Landed in many errors during execution.. And finally the waterfall danced with my FM station at 103.3MHz.

And the most beautiful thing is that the FM station is a Raspberry Pi running the PiFm project.
1. Compile PiFm project with
     gcc -lm -std=c99 -o pifm1 pifm.c
2. run the PiFm transmitter with below command
    sudo ./pifm1 sound.wav 95.3
this transmits the file sound.wav at 95.3 Mhz






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