Q&A for How to Make an FM Antenna

The dipole antenna is a simple antenna consisting of two rods or wires of exactly the same type and length, which serve as the conductive elements for the electrical energy. The current is applied (transmitter) or taken (receiver) from between the two halves of the antenna. To help you get an image, just think of the "rabbit’s ears" used for broadcast television sets. You can find greater detail on how this antenna works in the Wikipedia article "Dipole antenna."

It is possible to use a CB antenna for FM radio. Some people like doing this to avoid having too many antennas or to keep things tidy in a vehicle or other place. It can be helpful to use a CB/FM splitter, that enables you to get the CB and FM reception. You can find instructions for using the CB antenna as an FM radio on various CB users’ forums online.

A transmitter FM antenna creates electrical signals or electrical energy and turns this energy into radio waves (electrons travel back and forth along the antenna, creating electromagnetic radiation). The electromagnetic radiation is better known as "radio waves" and these waves then travel long distances, carrying the sounds, songs, talk, etc. you’re familiar with on radio. A receiver antenna (on your radio, for example) captures the radio waves that have been transmitted, and the electric current generated is converted by your radio into the sounds you enjoy listening to. The bigger or more powerful the antennas, the farther the radio waves will travel.

If the digital TV antenna is able to receive VHF television signals, then it may work for FM radio, as the frequencies are quite close. However, most TV is on the UHF band now, so any digital antenna that is made only to receive these frequencies won’t work well for FM radio.

FM radio does not come from a satellite. It comes from ground stations. A satellite dish will not help you get better FM radio reception.

Perpendicular. The radio waves have to intersect the metal of the antenna to cause a small voltage. Parallel to the transmitter offers much less harmoic area to intercept the radio waves.

Look at the back of your radio and find the external antenna connection. Match the connectors on the radio to an appropriate type of connection fitting, and put two and two together. This is a very simple process unless your radio has no provision for an external antenna.

Home improvement stores should carry it.

You can create your own horizontal piece by using a piece of the 300 ohm cable. Length will be a multiple of 37.66". Each end will be stripped back about 1/2", and then the exposed wires will be bent to touch each other and soldered together. Insulate the ends. Then, in the center of this piece, carefully expose about 3/4" of one of the wires. This becomes your horizontal piece, with the exposed cut side being the 'bottom'.

You intersect the waves with all of the antennae. Ideally, you'd make the length of the lead from the antenna to the receiver a multiple of 5/8th, too

No, it doesn't. It's only the height that affects it (according to the height of the frequencies).

Your phone most likely already has FM radio as a feature. If not, you need to find a workaround. You can visit the FM station's website and listen to the feed there (or through a SHOUTcast or similar stream), or you may be able to connect a Bluetooth transmitter to a nearby FM radio.

Yes, copper is a good conductor for antennas. Usually, the thicker the material that's used, the better bandwidth you'll obtain upon tuning. Hollow antennas have different effects at different frequencies, and there is a skin effect that could also come into play depending on whether or not it's fully copper. A lot of variables come into play, but you aren't losing anything significant unless you're trying to get that signal to the moon.

Antennas aren't extraordinarily picky on the receiving side. If you plan to use multiple horizontal dipole antennas, consider using a combiner. Multiple dipoles can increase your gain. As soon as you want to use a vertical feed, remember that the polarization is affected from your feed line. I would suggest keeping your feed line among all horizontal dipoles. Your connections to the dipoles should go to a combiner. Unless you are trying to build a yagi or log periodic, then you may need to research that more. The difficulty of the log periodic or yagi is high, and one mistake could lead you to a similar gain as just one dipole.

I would try hitting a flea market or some yard/garage sales and looking for an old radio or two that you can use for parts, take the radio antennas off of them and see if they will work.

Connecting a random length of wire to the telescopic "rod" antenna usually improves reception somewhat. It is important to have a solid connection between the rod and the added wire with as much contact area as possible between the two. An alligato-type clip with the wire connected with solder or via a terminal screw works about as well as you can expect. Connect the alligator clip to the base of the rod antenna and experiment with different positions of both the wire and telescopic rod to find the best results.

The antenna inside the radio may be disabled when connecting an external dipole antenna. If the dipole is inferior either due to design or defect, it could be the cause of poor reception when connected.

Try connecting about 6 feet of insulated wire with an alligator clip. If that doesn't work, try connecting to the TV antenna.