[BC] Directional FM Antennas

[Tom Dimeo]

Are directional FM transmitting antennas phased in a similar 
way as AM directional systems?  If so, is phase monitoring, 
loop current monitoring, common point monitoring etc. required?

If the directivity is accomplished using parasitic elements 
as many amateur antennas do, are the directional 
characteristics monitored in some way?

Tom (just an amateur) does it show?