diff --git a/Modulator.cpp b/Modulator.cpp
index a4358bbd4..af7d31aa8 100644
--- a/Modulator.cpp
+++ b/Modulator.cpp
@@ -29,6 +29,8 @@ Modulator::Modulator (unsigned frameRate, unsigned periodLengthInSeconds, QObjec
   , m_stream {nullptr}
   , m_quickClose {false}
   , m_phi {0.0}
+  , m_toneSpacing {0.0}
+  , m_fSpread {0.0}
   , m_frameRate {frameRate}
   , m_period {periodLengthInSeconds}
   , m_state {Idle}
@@ -40,7 +42,7 @@ Modulator::Modulator (unsigned frameRate, unsigned periodLengthInSeconds, QObjec
                                                 // seed
 }
 
-void Modulator::start (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, SoundOutput * stream, Channel channel, bool synchronize, double dBSNR)
+void Modulator::start (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, double toneSpacing, SoundOutput * stream, Channel channel, bool synchronize, double dBSNR)
 {
   Q_ASSERT (stream);
 
@@ -62,6 +64,7 @@ void Modulator::start (unsigned symbolsLength, double framesPerSymbol, unsigned
   m_nsps = framesPerSymbol;
   m_frequency = frequency;
   m_amp = std::numeric_limits<qint16>::max ();
+  m_toneSpacing = toneSpacing;
 
   // noise generator parameters
   if (m_addNoise) {
diff --git a/Modulator.hpp b/Modulator.hpp
index 88ece3f4b..365d7da09 100644
--- a/Modulator.hpp
+++ b/Modulator.hpp
@@ -30,9 +30,9 @@ public:
   bool isMuted () const {return m_muted;}
   unsigned frequency () const {return m_frequency;}
   bool isActive () const {return m_state != Idle;}
-  void setWide9(double d1, double d2) {m_toneSpacing=d1; m_fSpread=d2;}
+  void setSpread(double s) {m_fSpread=s;}
 
-  Q_SLOT void start (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, SoundOutput *, Channel = Mono, bool synchronize = true, double dBSNR = 99.);
+  Q_SLOT void start (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, double toneSpacing, SoundOutput *, Channel = Mono, bool synchronize = true, double dBSNR = 99.);
   Q_SLOT void stop (bool quick = false);
   Q_SLOT void tune (bool newState = true);
   Q_SLOT void mute (bool newState = true) {m_muted = newState;}
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 7d33f7bf3..47d1fb3e0 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -1667,7 +1667,7 @@ void MainWindow::startTx2()
     double snr=99.0;
     QString t=ui->tx5->currentText();
     if(t.mid(0,1)=="#") fSpread=t.mid(1,5).toDouble();
-    m_modulator.setWide9(m_toneSpacing, fSpread);
+    m_modulator.setSpread(fSpread);
     t=ui->tx6->text();
     if(t.mid(0,1)=="#") snr=t.mid(1,5).toDouble();
     if(snr>0.0 or snr < -50.0) snr=99.0;
@@ -2841,11 +2841,11 @@ void MainWindow::transmit (double snr)
 {
   if (m_modeTx == "JT65")
     {
-      Q_EMIT sendMessage (NUM_JT65_SYMBOLS, 4096.0 * 12000.0 / 11025.0, m_txFreq - m_XIT, &m_soundOutput, m_config.audio_output_channel (), true, snr);
+      Q_EMIT sendMessage (NUM_JT65_SYMBOLS, 4096.0 * 12000.0 / 11025.0, m_txFreq - m_XIT, m_toneSpacing, &m_soundOutput, m_config.audio_output_channel (), true, snr);
     }
   else
     {
-      Q_EMIT sendMessage (NUM_JT9_SYMBOLS, m_nsps, m_txFreq - m_XIT, &m_soundOutput, m_config.audio_output_channel (), true, snr);
+      Q_EMIT sendMessage (NUM_JT9_SYMBOLS, m_nsps, m_txFreq - m_XIT, m_toneSpacing, &m_soundOutput, m_config.audio_output_channel (), true, snr);
     }
 }
 
diff --git a/mainwindow.h b/mainwindow.h
index 7ed28f79f..b5b3014ff 100644
--- a/mainwindow.h
+++ b/mainwindow.h
@@ -192,7 +192,7 @@ private:
   Q_SIGNAL void transmitFrequency (unsigned) const;
   Q_SIGNAL void endTransmitMessage (bool quick = false) const;
   Q_SIGNAL void tune (bool = true) const;
-  Q_SIGNAL void sendMessage (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, SoundOutput *, AudioDevice::Channel = AudioDevice::Mono, bool synchronize = true, double dBSNR = 99.) const;
+  Q_SIGNAL void sendMessage (unsigned symbolsLength, double framesPerSymbol, unsigned frequency, double toneSpacing, SoundOutput *, AudioDevice::Channel = AudioDevice::Mono, bool synchronize = true, double dBSNR = 99.) const;
   Q_SIGNAL void outAttenuationChanged (qreal) const;
 
 private: