diff --git a/plugins/channeltx/modnfm/nfmmod.cpp b/plugins/channeltx/modnfm/nfmmod.cpp
index 4923f1993..8fdda4c9d 100644
--- a/plugins/channeltx/modnfm/nfmmod.cpp
+++ b/plugins/channeltx/modnfm/nfmmod.cpp
@@ -67,6 +67,7 @@ NFMMod::NFMMod() :
 	m_magsq = 0.0;
 
 	m_toneNco.setFreq(1000.0, m_config.m_audioSampleRate);
+	m_ctcssNco.setFreq(88.5, m_config.m_audioSampleRate);
 	DSPEngine::instance()->addAudioSource(&m_audioFifo);
 
     // CW keyer
@@ -88,9 +89,19 @@ void NFMMod::configure(MessageQueue* messageQueue,
 		float toneFrequency,
 		float volumeFactor,
 		bool audioMute,
-		bool playLoop)
+		bool playLoop,
+		bool ctcssOn,
+		float ctcssFrequency)
 {
-	Message* cmd = MsgConfigureNFMMod::create(rfBandwidth, afBandwidth, fmDeviation, toneFrequency, volumeFactor, audioMute, playLoop);
+	Message* cmd = MsgConfigureNFMMod::create(rfBandwidth,
+	        afBandwidth,
+	        fmDeviation,
+	        toneFrequency,
+	        volumeFactor,
+	        audioMute,
+	        playLoop,
+	        ctcssOn,
+	        ctcssFrequency);
 	messageQueue->push(cmd);
 }
 
@@ -140,10 +151,18 @@ void NFMMod::modulateSample()
     pullAF(t);
     calculateLevel(t);
 
-    // 378 = 302 * 1.25; 302 = number of filter taps (established experimentally)
-    m_modPhasor += (m_running.m_fmDeviation / (float) m_running.m_audioSampleRate) * m_bandpass.filter(t) * (M_PI / 378.0f);
-    m_modSample.real(cos(m_modPhasor) * 32678.0f);
-    m_modSample.imag(sin(m_modPhasor) * 32678.0f);
+    if (m_running.m_ctcssOn)
+    {
+        m_modPhasor += (m_running.m_fmDeviation / (float) m_running.m_audioSampleRate) * (0.85f * m_bandpass.filter(t) + 0.15f * 378.0f * m_ctcssNco.next()) * (M_PI / 378.0f);
+    }
+    else
+    {
+        // 378 = 302 * 1.25; 302 = number of filter taps (established experimentally)
+        m_modPhasor += (m_running.m_fmDeviation / (float) m_running.m_audioSampleRate) * m_bandpass.filter(t) * (M_PI / 378.0f);
+    }
+
+    m_modSample.real(cos(m_modPhasor) * 29204.0f); // -1 dB
+    m_modSample.imag(sin(m_modPhasor) * 29204.0f);
 }
 
 void NFMMod::pullAF(Real& sample)
@@ -275,6 +294,8 @@ bool NFMMod::handleMessage(const Message& cmd)
 		m_config.m_volumeFactor = cfg.getVolumeFactor();
 		m_config.m_audioMute = cfg.getAudioMute();
 		m_config.m_playLoop = cfg.getPlayLoop();
+		m_config.m_ctcssOn = cfg.getCTCSSOn();
+		m_config.m_ctcssFrequency = cfg.getCTCSSFrequency();
 
 		apply();
 
@@ -285,7 +306,9 @@ bool NFMMod::handleMessage(const Message& cmd)
                 << " m_toneFrequency: " << m_config.m_toneFrequency
                 << " m_volumeFactor: " << m_config.m_volumeFactor
 				<< " m_audioMute: " << m_config.m_audioMute
-				<< " m_playLoop: " << m_config.m_playLoop;
+				<< " m_playLoop: " << m_config.m_playLoop
+				<< " m_ctcssOn: " << m_config.m_ctcssOn
+				<< " m_ctcssFrequency: " << m_config.m_ctcssFrequency;
 
 		return true;
 	}
@@ -378,6 +401,14 @@ void NFMMod::apply()
         m_cwSmoother.setNbFadeSamples(m_config.m_audioSampleRate / 250); // 4 ms
     }
 
+    if ((m_config.m_ctcssFrequency != m_running.m_ctcssFrequency) ||
+        (m_config.m_audioSampleRate != m_running.m_audioSampleRate))
+    {
+        m_settingsMutex.lock();
+        m_ctcssNco.setFreq(m_config.m_ctcssFrequency, m_config.m_audioSampleRate);
+        m_settingsMutex.unlock();
+    }
+
 	m_running.m_outputSampleRate = m_config.m_outputSampleRate;
 	m_running.m_inputFrequencyOffset = m_config.m_inputFrequencyOffset;
 	m_running.m_rfBandwidth = m_config.m_rfBandwidth;
@@ -387,6 +418,8 @@ void NFMMod::apply()
 	m_running.m_audioSampleRate = m_config.m_audioSampleRate;
 	m_running.m_audioMute = m_config.m_audioMute;
 	m_running.m_playLoop = m_config.m_playLoop;
+	m_running.m_ctcssOn = m_config.m_ctcssOn;
+	m_running.m_ctcssFrequency = m_config.m_ctcssFrequency;
 }
 
 void NFMMod::openFileStream()
diff --git a/plugins/channeltx/modnfm/nfmmod.h b/plugins/channeltx/modnfm/nfmmod.h
index 9cc54cfa0..7dd3b9375 100644
--- a/plugins/channeltx/modnfm/nfmmod.h
+++ b/plugins/channeltx/modnfm/nfmmod.h
@@ -24,6 +24,7 @@
 
 #include "dsp/basebandsamplesource.h"
 #include "dsp/nco.h"
+#include "dsp/ncof.h"
 #include "dsp/interpolator.h"
 #include "dsp/lowpass.h"
 #include "dsp/bandpass.h"
@@ -184,7 +185,9 @@ public:
             float toneFrequency,
 			float volumeFactor,
             bool audioMute,
-            bool playLoop);
+            bool playLoop,
+            bool ctcssOn,
+            float ctcssFrequency);
 
     virtual void pull(Sample& sample);
     virtual void start();
@@ -218,10 +221,28 @@ private:
         float getVolumeFactor() const { return m_volumeFactor; }
         bool getAudioMute() const { return m_audioMute; }
         bool getPlayLoop() const { return m_playLoop; }
+        bool getCTCSSOn() const { return m_ctcssOn; }
+        float getCTCSSFrequency() const { return m_ctcssFrequency; }
 
-        static MsgConfigureNFMMod* create(Real rfBandwidth, Real afBandwidth, float fmDeviation, float toneFrequency, float volumeFactor, bool audioMute, bool playLoop)
+        static MsgConfigureNFMMod* create(Real rfBandwidth,
+                Real afBandwidth,
+                float fmDeviation,
+                float toneFrequency,
+                float volumeFactor,
+                bool audioMute,
+                bool playLoop,
+                bool ctcssOn,
+                float ctcssFrequency)
         {
-            return new MsgConfigureNFMMod(rfBandwidth, afBandwidth, fmDeviation, toneFrequency, volumeFactor, audioMute, playLoop);
+            return new MsgConfigureNFMMod(rfBandwidth,
+                    afBandwidth,
+                    fmDeviation,
+                    toneFrequency,
+                    volumeFactor,
+                    audioMute,
+                    playLoop,
+                    ctcssOn,
+                    ctcssFrequency);
         }
 
     private:
@@ -232,8 +253,18 @@ private:
         float m_volumeFactor;
         bool m_audioMute;
         bool m_playLoop;
+        bool m_ctcssOn;
+        float m_ctcssFrequency;
 
-        MsgConfigureNFMMod(Real rfBandwidth, Real afBandwidth, float fmDeviation, float toneFrequency, float volumeFactor, bool audioMute, bool playLoop) :
+        MsgConfigureNFMMod(Real rfBandwidth,
+                Real afBandwidth,
+                float fmDeviation,
+                float toneFrequency,
+                float volumeFactor,
+                bool audioMute,
+                bool playLoop,
+                bool ctcssOn,
+                float ctcssFrequency) :
             Message(),
             m_rfBandwidth(rfBandwidth),
             m_afBandwidth(afBandwidth),
@@ -241,7 +272,9 @@ private:
             m_toneFrequency(toneFrequency),
             m_volumeFactor(volumeFactor),
             m_audioMute(audioMute),
-			m_playLoop(playLoop)
+			m_playLoop(playLoop),
+			m_ctcssOn(ctcssOn),
+			m_ctcssFrequency(ctcssFrequency)
         { }
     };
 
@@ -269,6 +302,8 @@ private:
         quint32 m_audioSampleRate;
         bool m_audioMute;
         bool m_playLoop;
+        bool m_ctcssOn;
+        float m_ctcssFrequency;
 
         Config() :
             m_outputSampleRate(-1),
@@ -280,7 +315,9 @@ private:
             m_volumeFactor(1.0f),
             m_audioSampleRate(0),
             m_audioMute(false),
-			m_playLoop(false)
+			m_playLoop(false),
+			m_ctcssOn(false),
+			m_ctcssFrequency(88.5)
         { }
     };
 
@@ -290,7 +327,8 @@ private:
     Config m_running;
 
     NCO m_carrierNco;
-    NCO m_toneNco;
+    NCOF m_toneNco;
+    NCOF m_ctcssNco;
     float m_modPhasor; //!< baseband modulator phasor
     Complex m_modSample;
     Interpolator m_interpolator;
diff --git a/plugins/channeltx/modnfm/nfmmodgui.cpp b/plugins/channeltx/modnfm/nfmmodgui.cpp
index c2ab2d722..1c8e998f5 100644
--- a/plugins/channeltx/modnfm/nfmmodgui.cpp
+++ b/plugins/channeltx/modnfm/nfmmodgui.cpp
@@ -330,6 +330,17 @@ void NFMModGUI::on_showFileDialog_clicked(bool checked)
     }
 }
 
+void NFMModGUI::on_ctcss_currentIndexChanged(int index)
+{
+    applySettings();
+}
+
+void NFMModGUI::on_ctcssOn_toggled(bool checked)
+{
+    applySettings();
+}
+
+
 void NFMModGUI::configureFileName()
 {
     qDebug() << "FileSourceGui::configureFileName: " << m_fileName.toStdString().c_str();
@@ -457,7 +468,9 @@ void NFMModGUI::applySettings()
 			ui->toneFrequency->value() * 10.0f,
 			ui->volume->value() / 10.0f,
 			ui->audioMute->isChecked(),
-			ui->playLoop->isChecked());
+			ui->playLoop->isChecked(),
+			ui->ctcssOn->isChecked(),
+			m_ctcssTones[ui->ctcss->currentIndex()]);
 	}
 }
 
diff --git a/plugins/channeltx/modnfm/nfmmodgui.h b/plugins/channeltx/modnfm/nfmmodgui.h
index 958e4340a..9dcae122c 100644
--- a/plugins/channeltx/modnfm/nfmmodgui.h
+++ b/plugins/channeltx/modnfm/nfmmodgui.h
@@ -76,6 +76,9 @@ private slots:
     void on_navTimeSlider_valueChanged(int value);
     void on_showFileDialog_clicked(bool checked);
 
+    void on_ctcss_currentIndexChanged(int index);
+    void on_ctcssOn_toggled(bool checked);
+
     void onWidgetRolled(QWidget* widget, bool rollDown);
     void onMenuDoubleClicked();