Index: trunk/BNC/src/bnctime.cpp
===================================================================
--- trunk/BNC/src/bnctime.cpp	(revision 4585)
+++ trunk/BNC/src/bnctime.cpp	(revision 4586)
@@ -64,4 +64,12 @@
     _mjd--;
   }
+  return *this;
+}
+
+// 
+//////////////////////////////////////////////////////////////////////////////
+bncTime& bncTime::setmjd(double mjddec) {
+  _mjd = static_cast<unsigned int>(mjddec);
+  _sec = (mjddec - _mjd)*86400.0;
   return *this;
 }
Index: trunk/BNC/src/bnctime.h
===================================================================
--- trunk/BNC/src/bnctime.h	(revision 4585)
+++ trunk/BNC/src/bnctime.h	(revision 4586)
@@ -15,4 +15,5 @@
   bncTime& set(int year, int month, int day, double daysec);
   bncTime& setmjd(double daysec, int mjd);
+  bncTime& setmjd(double mjddec);
 
   void         reset() {_mjd = 0; _sec = 0;}
Index: trunk/BNC/src/rinex/availplot.cpp
===================================================================
--- trunk/BNC/src/rinex/availplot.cpp	(revision 4585)
+++ trunk/BNC/src/rinex/availplot.cpp	(revision 4586)
@@ -2,8 +2,23 @@
 #include <qwt_symbol.h>
 #include <qwt_plot_curve.h>
+#include <qwt_scale_draw.h>
+#include <qwt_text.h>
 
 #include "availplot.h"
 #include "reqcanalyze.h"
 
+//
+//////////////////////////////////////////////////////////////////////////////
+class t_scaleDraw : public QwtScaleDraw {
+ public:
+  t_scaleDraw() {}
+  virtual QwtText label(double mjd) const {
+    bncTime epoTime; epoTime.setmjd(mjd);
+    return QwtText(epoTime.timestr(0,':').c_str());
+  }
+};
+
+//
+//////////////////////////////////////////////////////////////////////////////
 t_availPlot::t_availPlot(QWidget* parent, 
                         QMap<QString, t_availData>* availDataMap) 
@@ -14,5 +29,8 @@
   // Axes
   // ----
-  setAxisTitle(QwtPlot::xBottom, "Epoch");
+  setAxisScaleDraw(QwtPlot::xBottom, new t_scaleDraw());
+  setAxisLabelRotation(QwtPlot::xBottom, -50.0);
+  setAxisLabelAlignment(QwtPlot::xBottom, Qt::AlignLeft | Qt::AlignBottom);
+
   setAxisTitle(QwtPlot::yLeft, "PRN");