Once again this generalization myth regarding TV antennas and FM reception comes up.
Old TV antenna.
This can mean many things. It may mean a TV antenna from the days of analog TV, the days of VHF low band, VHF high band and UHF. Or it may mean a TV antenna from after the transition from analog over the air to digital over the air. With the advent of digital over the air TV the channels were re-farmed (moved). Most ended up in the UHF range and the VHF high range and not all TV antennas offered much in the way of performance for the VHF low band channels and this would severely limit their performance on the FM broadcast band.
Starting with
cheaply, the TV antenna will still require all that goes along with mounting an antenna outside
and the TV antenna will likely have a much higher wind loading factor than a purpose designed FM broadcast antenna. This means a more robust and likely more expensive installation.
Performance.
Not all TV antennas are created equal when it comes to FM broadcast band reception. See the picture below.
View attachment 953500
Because the gain scale on the left is in dBi, I have added the yellow line that shows
zero dB gain relative to a basic dipole antenna and the black line that shows what happens to the
gain (actually lack of) above about 92 MHz.
I do not understand why anyone would make a blanket recommendation for using an old TV antenna and claim that they will work as well as a purpose designed FM broadcast antenna when this clearly may not be the case.
Antennas like the Stellar Labs yagi are available for about 30 dollars. This antenna provides about 5 dBd of net gain across the entire FM broadcast band and has a considerably smaller wind loading factor than most TV antennas.
Back on topic, the OP is in search of an indoor antenna and may not want to or be able to install an outdoor antenna.
Ryan, regardless of what others may post, the only way that you will know what will work in your situation is to pick an antenna and try it. It is not a bad idea to start with the basic dipole antenna or a rabbit ear style antenna. This can give you an idea in rough terms of the signal strength of your stations of interest.
Are all of your stations of interest located in the same direction from your location?