GM and DR cards to be written to the list. This
will automatically set the required wire removal conditions on the ``Symmetry
Bar''. Note: The user is allowed to change this ``Symmetry Bar'' setting(s) after the Control Card editing has been completed. This should not be done unless the appropriate Control Card symmetry options have been changed accordingly.
The user can also determine the existence and type of ground plane, its
parameters (including a ground screen if the reflection coefficient
approximation is chosen), whether the wires are connected to the ground plane
(in other words interpolated to their images), and specify the error testing
capabilities build into NEC4.1 This
will result in a GE and, if required, a GD card being added to
the list. (Note: NEC2 users should use the default in the ``Error testing'' box. Other ``Error testing'' options can cause NEC2 to crash.)