A year ago, the FCC approved the use of a computer modeling technique, known as "moment method modeling", to allow certain AM stations to do Proofs of Performance of directional antenna patterns without the costly and time-consuming process of proofing the antenna performance through the use of actual field strength measurements. 
series fed antenna
AM Proof of Performance Becomes Easier – And May Change The Way New Tower Owners Deal With Nearby AM Stations
By David Oxenford on
Posted in AM Radio, Tower Issues
In a recent decision, the FCC adopted new rules for AM station proofs of performance that make the process much simpler. We wrote about this proposal when it was advanced, here. The order adopted a week ago allows stations installing new series fed AM directional antennas to avoid the time-consuming and expensive process of…