diff --git a/software/drsosc/ConfigDialog.cpp b/software/drsosc/ConfigDialog.cpp
index 5c24577..4192722 100644
--- a/software/drsosc/ConfigDialog.cpp
+++ b/software/drsosc/ConfigDialog.cpp
@@ -150,7 +150,7 @@ void ConfigDialog::UpdateControls()
       m_cbExtRefclk->SetValue(m_osci->GetBoard(m_board)->GetRefclk() == 1);
 
       if ((m_osci->GetBoard(m_board)->GetBoardType() == 8 || m_osci->GetBoard(m_board)->GetBoardType() == 9)
-           && (!m_osci->IsMultiBoard() || m_board == 0))
+           && !(m_osci->IsMultiBoard() && !m_frame->IsTranspTrigger() && m_board > 0))
          m_frame->EnableTriggerConfig(true);
       else
          m_frame->EnableTriggerConfig(false);
@@ -178,7 +178,7 @@ void ConfigDialog::OnBoardSelect( wxCommandEvent& event )
                                wxT("DRS Oscilloscope"), wxOK | wxICON_STOP, this);
                } else {
                   if (b->GetScaler(5) < 300000) {
-                     str.Printf(wxT("No clock signal connected to CLK IN of board #%d"), i);
+                     str.Printf(wxT("No clock signal connected to CLK IN of board #%d. Keeping internal clock."), m_frame->GetOsci()->GetBoard(i)->GetBoardSerialNumber());
                      wxMessageBox(str, wxT("DRS Oscilloscope"), wxOK | wxICON_STOP, this);
                      m_frame->SetRefclk(i, false);
                   } else {
diff --git a/software/drsosc/DOFrame.cpp b/software/drsosc/DOFrame.cpp
index 4f342b1..2ce34de 100644
--- a/software/drsosc/DOFrame.cpp
+++ b/software/drsosc/DOFrame.cpp
@@ -93,6 +93,7 @@ DOFrame_fb( parent )
    m_chnSection = 0;
    m_multiBoard = false;
    m_splitMode = false;
+   m_transpTrigger = false;
 
    // initialize settings
    m_trgCorr = true;
@@ -357,7 +358,7 @@ void DOFrame::ClearWaveforms()
 
 void DOFrame::UpdateControls()
 {
-   if (m_osci->IsMultiBoard() && m_board > 0) {
+   if (m_osci->IsMultiBoard() && !m_transpTrigger && m_board > 0) {
       m_slTrgLevel->Enable(false);
       m_rbAuto->Enable(false);
       m_rbNormal->Enable(false);
@@ -434,7 +435,7 @@ void DOFrame::UpdateControls()
       if (m_osci->GetCurrentBoard()->GetBoardType() < 8) {
          EnableTriggerConfig(false);
       } else {
-         if (m_osci->IsMultiBoard() && m_board > 0)
+         if (m_osci->IsMultiBoard() && !m_transpTrigger && m_board > 0)
             EnableTriggerConfig(false);
          else
             EnableTriggerConfig(true);
@@ -529,6 +530,9 @@ void DOFrame::SaveConfig()
    sprintf(str, "%d", (int)m_splitMode);
    mxml_write_element(xml, "SplitMode", str);
 
+   sprintf(str, "%d", (int)m_transpTrigger);
+   mxml_write_element(xml, "TranspTrig", str);
+
    for (int b=0 ; b<m_osci->GetNumberOfBoards() ; b++) {
       sprintf(str, "Board-%d", m_osci->GetBoard(b)->GetBoardSerialNumber());
       mxml_start_element(xml, str);
@@ -649,6 +653,9 @@ void DOFrame::LoadConfig(char *error, int size)
    node = mxml_find_node(osc, "SplitMode");
    if (node) m_splitMode = atoi(mxml_get_value(node)) > 0;
 
+   node = mxml_find_node(osc, "TranspTrig");
+   if (node) m_transpTrigger = atoi(mxml_get_value(node)) > 0;
+
    for (i=idx=0 ; ; i++) {
       PMXML_NODE b = mxml_subnode(osc, i);
       if (!b)
@@ -1691,18 +1698,60 @@ void DOFrame::SetTriggerConfig(int id, bool flag)
 
    if (id == ID_TRANS) {
       if (flag) {
-         m_trgConfig[m_board] |= (1<<15);
-         m_trgConfig[m_board] &= ~((1<<4) | (1<<12)); // remove possible EXT trigger
-      } else
-         m_trgConfig[m_board] &= ~(1<<15);
+         // turn on transparent mode for all boards in multi-board mode
+         if (m_multiBoard) {
+            m_transpTrigger = true;
+            for (int i=0 ; i<m_osci->GetNumberOfBoards() ; i++) {
+               m_trgConfig[i] |= (1<<15);
+               m_trgConfig[i] &= ~((1<<4) | (1<<12)); // remove possible EXT trigger
+            }
+         } else {
+            m_transpTrigger = false;
+            m_trgConfig[m_board] |= (1<<15);
+            m_trgConfig[m_board] &= ~((1<<4) | (1<<12)); // remove possible EXT trigger
+         }
+         
+         // if no channel selected, select first one
+         if ((m_trgConfig[m_board] & 0x7FFF) == 0) {
+            m_trgConfig[m_board] |= 1;
+            DOFrame::SelectBoard(m_board);
+         }
+
+      } else {
+         m_transpTrigger = false;
+         if (m_multiBoard) {
+            for (int i=0 ; i<m_osci->GetNumberOfBoards() ; i++) {
+               m_trgConfig[i] &= ~(1<<15);
+            }
+         } else
+            m_trgConfig[m_board] &= ~(1<<15);
+      }
    }
    
    if ((m_trgConfig[m_board] & 0x7FFF) > 0) {
       m_rbSource->Enable(false);
-      m_osci->SetTriggerConfig(m_trgConfig[m_board]);
+      if (m_multiBoard) {
+         int b = m_board;
+         for (int i=0 ; i<m_osci->GetNumberOfBoards() ; i++) {
+            m_board = i;
+            m_osci->SetTriggerConfig(m_trgConfig[i]);
+         }
+         m_board = b;
+      } else {
+         m_osci->SetTriggerConfig(m_trgConfig[m_board]);
+      }
    } else {
       m_rbSource->Enable(true);
-      m_osci->SetTriggerSource(m_trgSource[m_board]);
+      if (m_multiBoard) {
+         int b = m_board;
+         for (int i=0 ; i<m_osci->GetNumberOfBoards() ; i++) {
+            m_board = i;
+            m_osci->SetTriggerSource(m_trgSource[i]);
+         }
+         m_board = b;
+      } else {
+         m_osci->SetTriggerSource(m_trgSource[m_board]);
+      }
    }
 
 }
diff --git a/software/drsosc/DOFrame.h b/software/drsosc/DOFrame.h
index 93f07f4..bff92b7 100644
--- a/software/drsosc/DOFrame.h
+++ b/software/drsosc/DOFrame.h
@@ -94,6 +94,7 @@ public:
    void SetTriggerConfig(int id, bool flag);
    void SetTriggerSource(int b, int source);
    void SetTriggerPolarity(int b, bool negative);
+   bool IsTranspTrigger() { return m_transpTrigger; }
    void SetStat(bool flag);
    void SetHist(bool flag);
    void SetStatNStat(int n);
@@ -224,6 +225,7 @@ private:
    int            m_chnSection;
    bool           m_multiBoard;
    bool           m_splitMode;
+   bool           m_transpTrigger;
 
    int            m_progress;
 };