Index: trunk/BNC/src/bncsp3.cpp
===================================================================
--- trunk/BNC/src/bncsp3.cpp	(revision 6532)
+++ trunk/BNC/src/bncsp3.cpp	(revision 6533)
@@ -188,4 +188,9 @@
     in >> sp3Sat->_prn >> sp3Sat->_xyz(1) >> sp3Sat->_xyz(2) >> sp3Sat->_xyz(3) >> sp3Sat->_clk; 
 
+    if (sp3Sat->_xyz.norm_Frobenius() == 0.0) {
+      delete sp3Sat;
+      continue;
+    }
+
     sp3Sat->_xyz *= 1.e3;
     if (sp3Sat->_clk == 999999.999999) {