rtl-sdr
turns your Realtek RTL2832 based DVB dongle into a SDR receiver
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For more information see:
https://osmocom.org/projects/rtl-sdr/wiki

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Modified RTL-SDR Blog Version
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1) VCO PLL current fix - Improves stability at frequencies above ~1.5 GHz https://www.rtl-sdr.com/beta-testing-a-modified-rtl-sdr-driver-for-l-band-heat-issues/
2) RTL_TCP ring buffer enhancement by Stephen Blinick https://www.rtl-sdr.com/significantly-improving-rtl_tcps-performance-with-ring-buffers/
3) Enabled direct sampling for rtl_tcp
4) rtl_biast program added, including the ability to turn on/off any GPIO
5) Hack to force the bias tee to always be on by setting the unused IR endpoint bit to 0 in the EEPROM. Example to force the BT to be always ON "rtl_eeprom -b y", to remove forced BT "rtl_eeprom -b n"
6) Hack to force direct sampling to be always on by setting the unused remote-enabled bit to 1 in the EEPROM. Example to force direct samping always "rtl_eeprom -q y". To remove forced direct sampling "rtl_eeprom -q n"
7) Repurposed "offset tuning" to toggle bias tee ON/OFF. We can now use the "offset tuning" button in SDR# and other programs to toggle the bias tee if there is no specific button in the GUI.
8) Windows released are linked against libusb 1.0.22 which apparently fixes issues for modern Ryzen motherboards.

BIAS TEE NOTE: Always take care that you do not enable the bias tee when the device is connected to a short circuited antenna unless there is an inline LNA. However. if you did by accident, don't worry as the circuit is dually protected with a self-resetting thermal fuse and built in protection on the LDO. Just try not to short it out for days at a time, otherwise you could eventually degrade the thermal fuse.

Note that hacks 5) and 6) will only work if your system is using this driver. If it uses another driver branch, then the EEPROM information will not be read. So make sure you completely clean your system of the previous drivers first (with the information below) and ensure you run sudo make install after compiling.

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Installation (Linux):
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***NOTE***
If you previously installed librtlsdr-dev via the package manager you should remove this first BEFORE installing these drivers. To completely remove these drivers use the following commands

sudo apt purge librtlsdr*
sudo rm -rvf /usr/lib/librtlsdr* /usr/include/rtl-sdr* /usr/local/lib/librtlsdr* /usr/local/include/rtl-sdr* /usr/local/include/rtl_*

***Now install the drivers***

sudo apt update
sudo apt install libusb-1.0-0-dev git cmake
git clone https://github.com/rtlsdrblog/rtl-sdr-blog
cd rtl-sdr-blog/
mkdir build
cd build
cmake ../ -DINSTALL_UDEV_RULES=ON
make
sudo make install
sudo cp ../rtl-sdr.rules /etc/udev/rules.d/
sudo ldconfig

echo 'blacklist dvb_usb_rtl28xxu' | sudo tee --append /etc/modprobe.d/blacklist-dvb_usb_rtl28xxu.conf

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Installation (Windows):
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Download the Release.zip file from the Releases page. Extract the librtlsdr.dll file to the SDR# folder, or whatever software is using it. Rename to rtlsdr.dll if necessary (e.g. SDR# looks for rtlsdr.dll instead of librtlsdr.dll)