Realtek 2832 EZCap - A Frugal SDR

Prereqs

A cheap spectrum analyzer

The steps below describe how to use a cheap USB TV dongle (RTL2832 EZCap) as a spectrum analyzer. This example uses node20-6.grid.orbit-lab.org since this has an attached RTL2832 device.

*) Load image ubuntu-14-04-64bit-sdr.ndz on node20-6.grid.orbit-lab.org then ssh in the node with X11 forwarding enabled. This image should have rtlsdr library already compiled.

grid> omf load -i ubuntu-14-04-64bit-sdr.ndz -t node20-6.grid.orbit-lab.org
grid> omf tell -a on -t node20-6.grid.orbit-lab.org
grid> ssh -Y node20-6

*) Install dependencies

root@node20-6:~# apt-get install python python-wxgtk2.8 python-matplotlib python-numpy python-imaging git cmake libusb-1.0-0-dev

*) Verify RTL2832 device is recognized by the node.

root@node20-6:~/rtl-sdr/src# lsusb | grep Realtek
Bus 002 Device 003: ID 0bda:2838 Realtek Semiconductor Corp. RTL2838 DVB-T

*) Remove default driver for RTL2832.

root@node20-6:~# modprobe -r dvb_usb_rtl28xxu

*) Verify RTL library has access to RTL2832

root@node20-6:~# cd ~/rtl-sdr/src
root@node20-6:~/rtl-sdr/src# ./rtl_test -t
Found 1 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000406

Using device 0: Generic RTL2832U OEM
Found Elonics E4000 tuner
Supported gain values (14): -1.0 1.5 4.0 6.5 9.0 11.5 14.0 16.5 19.0 21.5 24.0 29.0 34.0 42.0
Sampling at 2048000 S/s.
Benchmarking E4000 PLL...
[E4K] PLL not locked for 52000000 Hz!
[E4K] PLL not locked for 2234000000 Hz!
[E4K] PLL not locked for 1117000000 Hz!
[E4K] PLL not locked for 1249000000 Hz!
E4K range: 53 to 2233 MHz
E4K L-band gap: 1117 to 1249 MHz

*) Install pyrtlsdr library which provides a Python API for the RTL library

root@node20-6:~# git clone git://github.com/roger-/pyrtlsdr.git
root@node20-6:~# cd pyrtlsdr
root@node20-6:~/pyrtlsdr# sudo python setup.py install
root@node20-6:~/pyrtlsdr# cd ..

*) Export Python variable

root@node20-6:~# export PYTHONPATH=$PYTHONPATH:/usr/lib/python2.7/dist-packages

*) Install RTLSDR-SCANNER gui

root@node20-6:~# git clone https://github.com/EarToEarOak/RTLSDR-Scanner.git
root@node20-6:~# cd RTLSDR-Scanner/src/
root@node20-6:~/RTLSDR-Scanner/src/# ./rtlsdr_scan.py &

Additional information

For additional details on RTLSDR-SCANNER check ​http://eartoearoak.com/software/rtlsdr-scanner