FM antenna made simple

I just put a splitter on my line from the over the air tv antenna.From where I live the tv & fm stations are all 40 or so air miles east of me.I use the button that cuts off any noise between stations I get 30 or so clear as a bell stations. Am I doing something wrong I don't know about? The antenna is one of those Radio Shack 19.95 jobs.

My Terk FM-Pro works great, and in NYC that says a lot.
Costs around $100-150, and can be hidden quite well despite its size. (about 4' long and 5" wide). Hats off to Sean for taking so much time to respond in great detail.

Av- nothing wrong at all, FM and TV same basic signal, just different frequencies (I think FM lies between two of the VHF channels). FYI, I think that Radio Shack has an amplified stick that appears to be the same as the Terk FM-Pro for a bit less $ (80-90). Works great here in Hartford, CT

Thanks for the conformation, Sw. You know us neurotics. I actually put the antenna up because I was tired of the 6bucks going to Direct Tv./for the local channels ea. mo. I did buy their (RS) amplified 29 or 39 job= not nearly as good as the 19/outside one. I bought my present fm tuner from Nanderson/ I figure him to be an fm god.I was embarrassed to ask him about a tv antenna/for FM.

Swampwalker,
I might be mistaken, but I had a "stick" from Radio Shack, and it was rather lousy. The Terk is very good. Of course we may be thinking of two different antennae, but I don't think so.