With most antennas, the answer is “Yes.”
How does this work?
The FM broadcast band sits just below VHF channel 7, and if your antenna is designed to get VHF reception at all, it’s going to get FM. There are a few cases where a specific antenna will have something called an “FM trap” built in that actually stops FM reception. If you don’t know if your antenna has one of these, it probably doesn’t. In fact FM traps are very rare these days.
You might need one of these
It doesn’t matter how old the antenna is, but if it’s so old that the wire coming out of it is flat, you may need a transformer to convert it to coaxial, unless your A/V receiver is also so old that it accepts a flat cable using two screws for the antenna connection. Another option is to find the connection point for the flat antenna and replace it with this balun pictured below. Both options will work well and it’s really up to you how to do it.
What about a UHF-only antenna?
Most UHF antennas will actually do a decent job of FM reception as well. UHF antennas don’t pick up the FM band by design, but they don’t block it either. It’s just that FM radio doesn’t require a very complex antenna for reception. If you have an antenna of any kind up on the roof it’s worth giving it a try.
In general, most antennas you’ll find for sale today are UHF/VHF antennas. There was a push about a decade ago to go to UHF-only because it was hoped that all TV channels would go into those frequencies. However, some broadcasters refused to give up their VHF frequencies. In a twist, some UHF channels have recently migrated back to VHF because some of the UHF frequency band has been given over to cellular companies to implement 5G.
How does the installation work?
To get FM reception into your A/V receiver, you’ll need to split the signal using any simple splitter. If your A/V receiver has an antenna input with two screws (and this would be an older receiver) you’ll need a transformer to change the signal to 300 ohms. Many A/V receivers have a simple push-on connection for an FM antenna, and for this you just need to use any F female “barrel” connector.