Index: trunk/BNC/combination/bnccomb.cpp
===================================================================
--- trunk/BNC/combination/bnccomb.cpp	(revision 3452)
+++ trunk/BNC/combination/bnccomb.cpp	(revision 3453)
@@ -122,4 +122,7 @@
       newAC->name       = hlp[1];
       newAC->weight     = hlp[2].toDouble();
+      if (_masterOrbitAC.isEmpty()) {
+        _masterOrbitAC = newAC->name;
+      }
       _ACs.append(newAC);
     }
@@ -361,4 +364,6 @@
   // Observation Statistics
   // ----------------------
+  bool    masterPresent = false;
+
   QListIterator<cmbAC*> icAC(_ACs);
   while (icAC.hasNext()) {
@@ -370,7 +375,27 @@
       if (corr->acName == AC->name) {
         AC->numObs += 1;
+        if (AC->name == _masterOrbitAC) {
+          masterPresent = true;
+        }
       }
     }
     out << AC->name.toAscii().data() << ": " << AC->numObs << endl;
+  }
+
+  // If Master not present, switch to another one
+  // --------------------------------------------
+  if (!masterPresent) {
+    QListIterator<cmbAC*> icAC(_ACs);
+    while (icAC.hasNext()) {
+      cmbAC* AC = icAC.next();
+      if (AC->numObs > 0) {
+        out << "Switching Master AC "
+            << _masterOrbitAC.toAscii().data() << " --> " 
+            << AC->name.toAscii().data()   << " " 
+            << _resTime.datestr().c_str()    << " " 
+            << _resTime.timestr().c_str()    << endl;
+        _masterOrbitAC = AC->name;
+      }
+    }
   }
 
@@ -425,5 +450,5 @@
     ++iObs;
 
-    if (numObs[prn] >= 3 && resCorr.find(prn) == resCorr.end()) {
+    if (corr->acName == _masterOrbitAC && resCorr.find(prn) == resCorr.end()) {
       resCorr[prn] = new t_corr(*corr);
     }
Index: trunk/BNC/combination/bnccomb.h
===================================================================
--- trunk/BNC/combination/bnccomb.h	(revision 3452)
+++ trunk/BNC/combination/bnccomb.h	(revision 3453)
@@ -88,4 +88,5 @@
   bncAntex*               _antex;
   double                  _MAXRES;
+  QString                 _masterOrbitAC;
 };