diff --git a/MessageAggregator.cpp b/MessageAggregator.cpp
index f4b0b8ec5..2471ec2a5 100644
--- a/MessageAggregator.cpp
+++ b/MessageAggregator.cpp
@@ -222,7 +222,7 @@ public:
         Q_EMIT do_free_text (id_, text, false);
       });
     connect (message_line_edit_, &QLineEdit::editingFinished, [this] () {
-        Q_EMIT do_free_text (id_, message_line_edit_->text (), !message_line_edit_->text ().isEmpty ());
+        Q_EMIT do_free_text (id_, message_line_edit_->text (), true);
       });
     control_layout->addLayout (form_layout);
     control_layout->addWidget (auto_off_button_);
diff --git a/NetworkMessage.hpp b/NetworkMessage.hpp
index cce1380b5..de18461d0 100644
--- a/NetworkMessage.hpp
+++ b/NetworkMessage.hpp
@@ -199,14 +199,29 @@
  *                         Send                   bool
  *
  *			This message  allows the server  to set the current  free text
- *			message content. Sending this  message is equivalent to typing
- *			a new  message (old contents  are discarded) in to  the WSJT-X
- *			free text message field or  "Tx5" field (both are updated) and
- *			if the Send  flag is set then clicking the  "Now" radio button
- *			for the  "Tx5" field  if tab  one is  current or  clicking the
- *			"Free msg"  radio button  if tab  two is  current.  It  is the
- *			responsibility  of  the sender  to  limit  the length  of  the
- *			message text and to limit it to legal message characters.
+ *			message content. Sending this  message with a non-empty "Text"
+ *			field is equivalent to typing  a new message (old contents are
+ *			discarded) in to  the WSJT-X free text message  field or "Tx5"
+ *			field (both  are updated) and if  the "Send" flag is  set then
+ *			clicking the "Now" radio button for the "Tx5" field if tab one
+ *			is current or clicking the "Free  msg" radio button if tab two
+ *			is current.
+ *
+ *			It is the responsibility of the  sender to limit the length of
+ *			the  message   text  and   to  limit   it  to   legal  message
+ *			characters. Despite this,  it may be difficult  for the sender
+ *			to determine the maximum message length without reimplementing
+ *			the complete message encoding protocol. Because of this is may
+ *			be better  to allow any  reasonable message length and  to let
+ *			the WSJT-X application encode and possibly truncate the actual
+ *			on-air message.
+ *
+ *			If the  message text is  empty the  meaning of the  message is
+ *			refined  to send  the  current free  text  unchanged when  the
+ *			"Send" flag is set or to  clear the current free text when the
+ *			"Send" flag is  unset.  Note that this API does  not include a
+ *			command to  determine the  contents of  the current  free text
+ *			message.
  */
 
 #include <QDataStream>
diff --git a/mainwindow.cpp b/mainwindow.cpp
index f27ff1e7c..f4694c3c4 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -201,22 +201,34 @@ MainWindow::MainWindow(bool multiple, QSettings * settings, QSharedMemory *shdme
     });
   connect (m_messageClient, &MessageClient::error, this, &MainWindow::networkError);
   connect (m_messageClient, &MessageClient::free_text, [this] (QString const& text, bool send) {
-    if (m_config.accept_udp_requests ()) {
-      if (0 == ui->tabWidget->currentIndex ()) {
-        ui->tx5->setCurrentText (text);
-        if (send) {
-          ui->txb5->click ();
-        } else {
-          ui->txrb5->click ();
-        }
-      } else if (1 == ui->tabWidget->currentIndex ()) {
-        ui->freeTextMsg->setCurrentText (text);
-        if (send) {
-          ui->rbFreeText->click ();
+      if (m_config.accept_udp_requests ()) {
+        // send + non-empty text means set and send the free text
+        // message, !send + non-empty text means set the current free
+        // text message, send + empty text means send the current free
+        // text message without change, !send + empty text means clear
+        // the current free text message
+        qDebug () << "Free text UDP message - text:" << text << "send:" << send << "text empty:" << text.isEmpty ();
+        if (0 == ui->tabWidget->currentIndex ()) {
+          if (!text.isEmpty ()) {
+            ui->tx5->setCurrentText (text);
+          }
+          if (send) {
+            ui->txb5->click ();
+          } else if (text.isEmpty ()) {
+            ui->tx5->setCurrentText (text);
+          }
+        } else if (1 == ui->tabWidget->currentIndex ()) {
+          if (!text.isEmpty ()) {
+            ui->freeTextMsg->setCurrentText (text);
+          }
+          if (send) {
+            ui->rbFreeText->click ();
+          } else if (text.isEmpty ()) {
+            ui->freeTextMsg->setCurrentText (text);
+          }
         }
       }
-    }
-  });
+    });
 
   // Hook up WSPR band hopping
   connect (ui->band_hopping_schedule_push_button, &QPushButton::clicked