I made my own T-shaped, half-wave folded dipole FM antenna out of some scrap speaker wire, and I'm able to clearly pick up a Canadian radio station 75 miles away with 3 out of 5 multipath bars for the signal quality, and 5 out of 5 multipath bars for all of my local FM stations within 20 miles. But the pink ribbon, T-shaped, half-wave dipole FM antenna that I purchased at the store for $7 gave me, at best, 0 out of 5 multipath bars for the dx signal quality, and there was a lot of static interference when tuned to the same distant Canadian station with the same tuner. And a lot of my local stations within 20 miles are only coming in at 3 out of 5 bars with that pink ribbon half-wave dipole FM antenna.
Why is this? Thick wire is a better conductor and less resistant than thin wire, and thus makes for better FM antenna reception when the radio waves flow over it. Therefore, a homemade thick wire FM antenna will often give you much better reception quality than a store bought thin wire FM antenna. And making a T-shaped, dipole FM antenna is both easy and inexpensive. The following instructions are for making a 57" half-wave folded dipole FM antenna which will cover all of the US FM wavelengths from 89.1 to 108.5 mHz.
You will need:
18 gauge speaker wire, at least 8 feet in length (joined 4' scrap lengths are what I used for mine), but 10 to 12 feet would be better
Marker or pen
Two 2' lengths of wooden dowel or other stiff, non-conductive material for mounting (optional)
Begin by pulling apart about 5' of the joined speaker wire into two single strands, but leave the rest of the speaker wire joined together for the tail. Using the utility knife, cut about 1" to 1.5" of insulation off of both single strand ends. Form a hook on the end of each wire, then hook the two wires together. Clamp the hooks down with your thumbs and then twist the wires in opposite directions to form a tight joint that won't pull apart easily. This exposed copper joint marks the center of the horizontal top of the T.
Measure 28.5" from the center point of the top of the T with the measuring tape. Place a mark there with your marker so you won't lose your place, then fold the wire in half at that location. A little electrical tape wound near the end will help the end point of the T keep its folded shape. Do this in both directions to complete the horizontal top of the T.
Make sure that both wires on the top, horizontal bar of the T are even in length from the end point to the center point, then wind a little electrical tape around both wires near the center point to help keep that evenly measured shape. The vertical tail of the T begins at the exact center of the horizontal top of the T, which is very easy to find because of the wire joint you made earlier. Wind a little electrical tape at the top of the vertical tail of the T to keep the previously separated wires together. Now you can use some electrical tape to cover the exposed wire.
And we're just about done. At the bottom of the tail of the T, remove about 1/2" of insulation from each strand of wire. Connect the exposed wires to the 300 ohm jacks of your AM/FM tuner. You should get very good local reception from your homemade FM antenna. But if you want even better dx FM reception to capture that far distant station, use some more electrical tape to mount your curling speaker wire onto a couple of straight wooden dowels to keep the top bar of the T straightened out. Then experiment with moving the horizontal bar of the T in different compass directions to get the best FM reception.