How to Make Your Own FM Antenna

Today, Mytour will show you how to build your own antenna to extend the range of your FM receiver. Depending on your preferred frequency, you can opt for coaxial cable or speaker wire.

Prepare the necessary materials. To make a straight antenna from coaxial cable, you will need the following materials:

• 50 Ohm (or 75 Ohm) coaxial cable with copper shielding.
• FM receiver with a coaxial connector.
• 9.5 mm diameter copper tube.
• Wire cutters.
• Metal saw.
• Soldering tool.

Calculate the length of the antenna. This will help you determine the length of the coaxial cable and copper tube you need to cut:

• Divide 468 by the frequency you want to connect (e.g., 468/108MHz = 4.3).
• Take the result and divide it by 2 (e.g., 4.3/2 = 2.15).
• Next, multiply by 30.5 cm (12 inches) to calculate the antenna length (e.g., 2.15*30.5 cm = 65.57 cm).

Cut one end of the coaxial cable. Keep one end of the coaxial cable for the connector, and cut off the other end.

• You can use wire cutters or a hacksaw to perform the cut.

Strip the outer jacket of the coaxial cable for half of its length. You need to remove each protective layer until you see the white insulation surrounding the inner core.

• For example, if the estimated antenna length is 15 cm, strip 7.5 cm of protective covering.
• Be sure to remove the copper shielding during this process. The easiest way is to use a saw to mark a shallow line around the cutting point and try to peel off the copper sheath from the cable.

Cut the copper tube to half the antenna length. This part forms the other half of the antenna, so the copper tube must be as long as the section you just stripped.

• As a reminder, if your antenna is 15 cm, the copper tube should be 7.5 cm long.

Insert the copper tube into the coaxial cable. Slide the copper tube into the stripped end of the coaxial cable and slide it down.

Solder the protective jacket of the coaxial cable to the copper tube. You can do this by cutting about 2.5 cm of the black PVC insulation directly below the stripped portion of the coaxial cable, then bending it back into a lip shape. Afterward, use a soldering iron to connect this lip to the copper shielding.

Connect the coaxial cable to the radio receiver. Insert the coaxial connector you kept into the coaxial antenna port on the receiver; the remaining portion will serve as the antenna.

Adjust the antenna. After connecting, direct the antenna towards the nearest broadcast station and secure it if necessary.

• The fewer obstacles between the antenna and the FM station, the stronger the signal you will receive.
• The coaxial cable is rigid enough to stay in the desired position without extra support, but you can use a stand or tape to secure the antenna if needed.

Know when to apply this method. If the FM signal is relatively stable but occasionally needs slight adjustments, you can use speaker wire as a range booster to enhance the connection quality.

• Speaker wire is not an ideal solution for long-range reception. If the signal continuously malfunctions, you should use coaxial cable.

Prepare the necessary materials. To create a makeshift antenna using speaker wire, you will need:

• 3 meters of speaker wire
• FM receiver with a clamp connector (or straight one)
• Wire stripper tool

Strip about 1 meter of speaker wire. Use a knife or wire stripper to remove about 1 meter of the wire in opposite directions. You should strip around 1 meter and leave 2 meters of wire intact.

Bend the speaker wire into a "T" shape. Fold each end of the stripped wire at a 90-degree angle to the remaining 2 meters of wire.

Strip about 5 cm of insulation from the remaining end of the speaker wire. Use the wire stripper tool for this task. Once stripped, you will have two exposed wire ends at the tip of the "T".

Locate the antenna port on the receiver device. Typically, there are two ports labeled "FM EXT" or "ANT EXT", but you will often find an "FM" port near the connection terminals; there may also be labels like "Balanced" or "BAL" near the corresponding connection ports.

• The FM receiver will have either a clamp-style connector or a straight one. The clamp connector is shaped to clamp, while the straight connector resembles a metal pin that plugs into a connection post.

Connect the lower part of the "T" speaker wire to the receiver. Use the bare wire at the bottom of the "T" that you stripped to connect it to the receiver's connector.

• If the receiver only has one connection port, twist the two bare wire ends at the bottom of the "T" together to form a single connection, which can then be attached to the clip or post.

Adjust the antenna. Ideally, you should position the antenna as high as possible and as close to the transmission station as you can. In some cases, this may require placing the antenna above a wall or outside.

• You may need to reposition the receiver to get the strongest signal.

• Both antenna types discussed in this article are "balanced" designs, which may be inconvenient when connecting to a "non-balanced" retractable antenna typically used.
• Coaxial cables and speaker wires are relatively inexpensive. If you already have the right tools to make an antenna, you can create one at a much lower cost than purchasing a new FM antenna.

• Outdoor antennas require solutions to handle weather conditions (for instance, waterproof junction boxes).
• If installing an outdoor antenna, additional lightning protection measures should be implemented.