diff --git a/Readme.md b/Readme.md
index 79128bc10..a7d258f04 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,3 +1,10 @@
+======================
+Cloning the repository
+======================
+
+- Clone as usual
+- Checkout the f4exb branch: `git checkout f4exb`
+
 ==============
 Funcube Dongle
 ==============
@@ -11,16 +18,29 @@ Funcube Dongle Pro+ USB drivers are broken on some hardware with recent kernels.
 For Ubuntu
 ==========
 
-"sudo apt-get install libqt5multimedia5-plugins qtmultimedia5-dev qttools5-dev qttools5-dev-tools libqt5opengl5-dev qtbase5-dev libusb-1.0 librtlsdr-dev"
+`sudo apt-get install libqt5multimedia5-plugins qtmultimedia5-dev qttools5-dev qttools5-dev-tools libqt5opengl5-dev qtbase5-dev libusb-1.0 librtlsdr-dev`
 
-"mkdir out && cd out && cmake ../ && make"
+`mkdir build && cd build && cmake ../ && make`
 
-"librtlsdr-dev" is in the "universe" repo. (utopic 14.10 amd64.)
+`librtlsdr-dev` is in the `universe` repo. (utopic 14.10 amd64.)
 
-Use "cmake ../ -DV4L-RTL=ON" to build the Linux kernel driver for RTL-SDR (Experimental). Needs a recent kernel and libv4l2. Will need extra work to support SDRPlay. Needs "cp KERNEL_SOURCE/include/linux/compiler.h /usr/include/linux/" and "cp KERNEL_SOURCE/include/uapi/linux/videodev2.h /usr/include/uapi/linux/" and package "libv4l-dev".
+Use `cmake ../ -DV4L-RTL=ON` to build the Linux kernel driver for RTL-SDR (Experimental). Needs a recent kernel and libv4l2. Will need extra work to support SDRPlay. Needs `cp KERNEL_SOURCE/include/linux/compiler.h /usr/include/linux/` and `cp KERNEL_SOURCE/include/uapi/linux/videodev2.h /usr/include/uapi/linux/` and package `libv4l-dev`.
 
-The Gnuradio plugin source needs extra packages, including "liblog4cpp-dev libboost-system-dev gnuradio-dev libosmosdr-dev"
+The Gnuradio plugin source needs extra packages, including `liblog4cpp-dev libboost-system-dev gnuradio-dev libosmosdr-dev`
 
+For non standard installations of RTL-SDR library, the GNU Radio runtime and gr.osmocom drivers use the following variables in the cmake command line. The paths specified are just examples:
+
+  - For GNU Radio runtime:
+    - Includes: `-DGNURADIO_RUNTIME_INCLUDE_DIRS=/opt/install/gnuradio-3.7.5.1/include`
+    - Library: `-DGNURADIO_RUNTIME_LIBRARIES=/opt/install/gnuradio-3.7.5.1/lib/libgnuradio-runtime.so`
+  - For gr.osmocom:
+    - Includes: `-DGNURADIO_OSMOSDR_INCLUDE_DIRS=/opt/install/gr-osmosdr/include`
+    - Library: `-DGNURADIO_OSMOSDR_LIBRARIES=/opt/install/gr-osmosdr/lib/libgnuradio-osmosdr.so`
+  - For RTL-SDR library:
+    - Includes: `-DLIBRTLSDR_INCLUDE_DIR=/opt/install/rtlsdr/include`
+    - Library: `-DLIBRTLSDR_LIBRARIES=/opt/install/rtlsdr/lib/librtlsdr.so`
+    
+There is no installation procedure the executable is at the root of the build directory
 
 ============
 For Debian 8
@@ -28,15 +48,38 @@ For Debian 8
 
 Debian 7 "wheezy" uses Qt4. Qt5 is available from the "wheezy-backports" repo, but this will remove Qt4.
 
-"sudo apt-get install cmake g++ pkg-config libfftw3-dev libusb-1.0-0-dev libusb-dev qt5-default qtbase5-dev qtchooser libqt5multimedia5-plugins qtmultimedia5-dev qttools5-dev qttools5-dev-tools libqt5opengl5-dev qtbase5-dev librtlsdr-dev"
+`sudo apt-get install cmake g++ pkg-config libfftw3-dev libusb-1.0-0-dev libusb-dev qt5-default qtbase5-dev qtchooser libqt5multimedia5-plugins qtmultimedia5-dev qttools5-dev qttools5-dev-tools libqt5opengl5-dev qtbase5-dev librtlsdr-dev`
 
-"mkdir out && cd out && cmake ../ && make"
+`mkdir out && cd out && cmake ../ && make`
+
+The same remarks as for Ubuntu apply...
 
 ============
 Known Issues
 ============
 
-FM is mostly untested.
+  - Actually NFM seems to be working pretty well
+  - WFM does not work for broadcast
+  - RTL frontend will have bad aliasing in noisy environments. Considering the size of the hardware there is no place for proper filters. With good filtering and a good antenna up front these devices work remarkably well for the price! 
 
-RTL frontend will have bad aliasing in noisy environments.
+===================
+Done since the fork
+===================
 
+  - Added ppm correction for the LO of RTL-SDR. This uses the corresponding function in the librtlsdr interface (range -99..99 ppm)
+  - Added a preset update button (the diskette with the yellow corner) to be able to save the current settings on an existing preset
+  - Added variable decimation in log2 increments from 2^0=1 to 2^4=16 allowing to see the full 2048 kHz of spectrum if so you wish
+  - Better handling of rtlsdr GUI display when settings change (initial load, load of presets)
+
+=====
+To Do
+=====
+
+  - Display center frequency of the receiver in scope. Presently there is no way to set the frequency precisely
+  - AM demod. What about the air band?!
+  - Add the possibility to change the brightness and/or color of the grid. Sometimes it is barely visible yet useful
+  - Possibility to completely undock the receiver in a separate window. Useful when there are many receivers
+  - Larger decimation capability for narrowband and very narrowband work (32, 64, ...)
+  - Even more demods ... 
+  - Triggering capability like on expensive spectrum analyzers to trap burst signals
+  - recording capability
diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
index b19455be4..3fa641344 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
@@ -1,3 +1,4 @@
+#include <iostream>
 #include "rtlsdrgui.h"
 #include "ui_rtlsdrgui.h"
 #include "plugin/pluginapi.h"
@@ -95,7 +96,13 @@ bool RTLSDRGui::handleMessage(Message* message)
 void RTLSDRGui::displaySettings()
 {
 	ui->centerFrequency->setValue(m_generalSettings.m_centerFrequency / 1000);
-	ui->samplerate->setValue(1);
+	ui->samplerateText->setText(tr("%1k").arg(m_settings.m_samplerate / 1000));
+	unsigned int sampleRateIndex = RTLSDRSampleRates::getRateIndex(m_settings.m_samplerate);
+	ui->samplerate->setValue(sampleRateIndex);
+	ui->ppm->setValue(m_settings.m_loPpmCorrection);
+	ui->ppmText->setText(tr("%1").arg(m_settings.m_loPpmCorrection));
+	ui->decimText->setText(tr("%1").arg(1<<m_settings.m_log2Decim));
+	ui->decim->setValue(m_settings.m_log2Decim);
 
 	if(m_gains.size() > 0) {
 		int dist = abs(m_settings.m_gain - m_gains[0]);
@@ -159,8 +166,7 @@ void RTLSDRGui::on_gain_valueChanged(int value)
 
 void RTLSDRGui::on_samplerate_valueChanged(int value)
 {
-	int Rates[] = {288, 1024, 1536, 1152, 2048, 2500 };
-	int newrate = Rates[value];
+	int newrate = RTLSDRSampleRates::getRate(value);
 	ui->samplerateText->setText(tr("%1k").arg(newrate));
 	m_settings.m_samplerate = newrate * 1000;
 	sendSettings();
@@ -193,3 +199,30 @@ void RTLSDRGui::on_checkBox_stateChanged(int state) {
 	sendSettings();
 }
 
+unsigned int RTLSDRSampleRates::m_rates[] = {288, 1024, 1536, 1152, 2048, 2500 };
+unsigned int RTLSDRSampleRates::m_nb_rates = 6;
+
+unsigned int RTLSDRSampleRates::getRate(unsigned int rate_index)
+{
+	if (rate_index < m_nb_rates)
+	{
+		return m_rates[rate_index];
+	}
+	else
+	{
+		return m_rates[0];
+	}
+}
+
+unsigned int RTLSDRSampleRates::getRateIndex(unsigned int rate)
+{
+	for (unsigned int i=0; i < m_nb_rates; i++)
+	{
+		if (rate/1000 == m_rates[i])
+		{
+			return i;
+		}
+	}
+
+	return 0;
+}
diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.h b/plugins/samplesource/rtlsdr/rtlsdrgui.h
index 7aa150443..a0882ce65 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.h
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.h
@@ -9,6 +9,7 @@ class PluginAPI;
 
 namespace Ui {
 	class RTLSDRGui;
+	class RTLSDRSampleRates;
 }
 
 class RTLSDRGui : public QWidget, public PluginGUI {
@@ -52,4 +53,13 @@ private slots:
 	void updateHardware();
 };
 
+class RTLSDRSampleRates {
+public:
+	static unsigned int getRate(unsigned int rate_index);
+	static unsigned int getRateIndex(unsigned int rate);
+private:
+	static unsigned int m_rates[6];
+	static unsigned int m_nb_rates;
+};
+
 #endif // INCLUDE_RTLSDRGUI_H
diff --git a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
index ca7e6c6d8..9d7f0d6bb 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
@@ -27,7 +27,9 @@ MESSAGE_CLASS_DEFINITION(RTLSDRInput::MsgReportRTLSDR, Message)
 
 RTLSDRInput::Settings::Settings() :
 	m_gain(0),
-	m_samplerate(1024000)
+	m_samplerate(1024000),
+	m_loPpmCorrection(0),
+	m_log2Decim(4)
 {
 }
 
@@ -60,7 +62,7 @@ bool RTLSDRInput::Settings::deserialize(const QByteArray& data)
 
 	if(d.getVersion() == 1) {
 		d.readS32(1, &m_gain, 0);
-		//d.readS32(2, &m_samplerate, 0);
+		d.readS32(2, &m_samplerate, 0);
 		d.readS32(3, &m_loPpmCorrection, 0);
 		d.readU32(4, &m_log2Decim, 4);
 		return true;