June 30, 2026 – “What is a Rubber Duck Antenna?”

Good evening. This is W1UT and tonight’s training is “What is a Rubber Duck Antenna?”

Most hams start out on VHF or UHF using a handheld radio. All of these radios come with what is called a rubber duck antenna. This type of antenna was invented way back in 1958 by Richard Johnson who lived in the Boston area. Another name for this antenna is “Stubby Antenna.” Before rubber ducks all portable antennas were quarter wave monopole whips. A quarter wave whip on the 2m band is approximately 19 inches in length and can be a bit unwieldy.

The name rubber duck comes from the rubber or plastic coating on the outside of the antenna for protection. Under the coating the antenna consists of a helically wound wire that is tuned to be close to 50 ohm impedance. The other half of the antenna is the handheld radio itself making the performance of the radio rather inefficient. These types of antennas have been tested by a number of hams who have found that they have negative gain compared to a quarter wave whip. In some cases as much as -6 to -8 db loss depending on the duck’s length and how well the radio provides the required other half of the dipole. What does -6 to -8 dB mean? If you set your radio to transmit 5W into your antenna and you have 6 dB of loss, this means the antenna radiating about 1.25W. At -8 dB the radiated power is about 0.8W. This is pretty significant.

Some hams have figured out a way to increase performance by adding a 19” wire tail to the outside of the antenna connector. Personally I have not found a significant difference. One modification you can use to improve performance is to make a 19” whip of wire and temporarily remove the rubber duck and replaceit with the 19” whip. Or you can simply purchase a Signal Stick made right here in Utah. You can also buy these right on Amazon.

Anyone who has done an internet search on replacement OEM rubber duck antennas can easily be overwhelmed. Claims of improved radio performance generally depends on the antenna’s length. While longer antennas do benefit from better performance, the trade off is hauling around an antenna that can poke into your arm pit when your radio is clipped to your belt or just become unwieldy. You will find however that a radio with a rubber duck will work better on UHF than on VHF as a quarter wave length on 70cm is much closer to a 6” quarter wave length. Hence less loss.

If a repeater is line of sight from your location then 5W from a rubber duck antenna will usually work well. If you try to make contact while inside your home, your car or somewhere else where line of sight is no longer possible you will likely have challenges. So keep this in mind.