Dipole Antenna

This is a basic dipole antenna. An antenna can be a great help in increasing the signal of your transmitter! The length is “quarter wave”, which can be calculated given your target frequency. This antenna is tuned for ~90MHz and should be about 62” tall (31” each leg).

Tools

Components

Overview

We’ll use a coax cable, which is comprised of a metallic shield and inner inductor, separated by insulating material…

You can turn it into an antenna, like so…

Instructions

Measure out 31” for the leg of your dipole and make an incision at that point:

Use a light touch, just score the coax shield across the 31” mark and be very careful not to cut any of the thin metallic strands within the shield. If you damage the metallic part, it will affect the signal!

Make a score vertically along the length of the cable and gradually unravel the plastic jacket from the metallic shield. From the score, you can kind of peel away the outer layer as you go:

Pull out the inner conductor completely from the metallic shield. You can do this by using a small pick or screwdriver to making a gap in the braded metallic sheild (without cutting it):

Your dialectric insulator might still be surrounded by a metal foil. Make sure to score and peel it off as well:

You should end up with two intact leads, like this:

Tape your leads to any non-conductive surface (a plank of wood, a broomstick, pvc pipe, etc.) You can also make a small coil at the base of the ‘Y’ which will act as a RF “choke”. It’s not neccessary but can help with signal quality:

One the other end, expose the leads in two so you can solder it to your transmitter. The inner conductor should connect to ground, the metallic shield should connect to the same place where you originally soldered your ‘stick’ (monopole) antenna: