That's a UHF antenna. It will probably suck badly for FM.
The size of the antenna is often a clue as to how the bottom of its response range is. Most markets don't have any low VHF channels (2 - 6) any more, so the six foot wide antennas are rarely needed. Unfortunately, FM is just above Channel 6.
This reminds me of the "bow-tie" antennas you still see sometimes. My grandfather had a quad bowtie on his house in the late 50s!
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw
