We know, seeing a tennis ball sticking on the tip of a vehicle’s antenna might be weird, yet there is more to it. Indeed, it provides a wide range of benefits to drivers yet also some complicated issues. If you also wonder why tennis balls on antenna, today’s article is for you.



Why Do People Put Tennis Balls On The Antenna? 

Vehicle owners have been putting tennis balls onto their transmitters for years to keep the antenna from slamming into their automobiles. Indeed, it is an efficient and low-cost approach to stop those whipping tips from damaging or scratching the outer body of your car.

Although the method has gone into the past, many young people still opt for customized tennis ball antennas due to their unique look. Imagine having a personalized ball on top of the transmitter! You could easily find your car in a crowded parking lot while showing your imprints to others.

One less widespread usage of this setup is actually to get people out of the way on the street. While adding a tennis ball onto your antenna erases the worry of scratching your vehicle, this ball can quickly smack other’s cars and result in several damages. Thus, when people see automobiles having tennis ball antennas, they tend to move over.

Does The Tennis Ball Affect The Antenna’s Performance?

Unfortunately, yes. 

We all know how antennas work: They act as transmitters of audio waves, video, or digital data via frequencies sent and delivered back and forth in an electromagnetic field. 

Thus, if anything is coming in between the transmitting device and the receiving ones, it will yield blockages or somewhat an effect on the broadcasted electromagnetic field. 

The potential effects might include deflections, reflections, distortions, and (or) absorption. At the same time, keep in mind that the smaller the distance from the blockage to the transmitting source, the more significant the effect will usually become. 

As near as you’ll ever get is to place the ball on top of the transmitting unit. Also, depending on the place you position your tennis ball and the height of the transmitter, it will have a different influence on the antenna’s characteristics and performance.

A tennis ball attached to a radio transmitter adds capacitive effects, causing a resonating wavelength movement and a variation in the standing wave ratio (SWR) at that frequency on a formerly adjusted antenna. The impact of moving the tennis ball upwards or downwards the antennas will affect the SWR.

On the other hand, if you’re using a top-loaded transmitter and thinking about attaching a ball, remember that the closer your ball is to the tip of the transmitter, the more significant the impact it will make on the antenna’s capabilities.

The reason for this is that when the frequency flow gets limited owing to increased electromagnetic fluxes in the antenna’s tight coiled zone, the voltage rises, making the atmosphere more receptive to everything in the surrounding zone of radiation.

How To Minimize The Effect Of Your Tennis Ball On The Antenna?

If you intend to utilize a tennis ball on your antenna, it’s a must to adjust the transmitter while the tennis ball is in its optimal settling position. You’ll have to configure the transmitter again if you install it after you’ve adjusted it.

Furthermore, it would help if you made a notation on the transmitter. Hence, you’ll remember precisely where the base or head of the ball was once you adjusted it. It’s essential since some knothead would unintentionally begin fiddling with the ball, altering the SWR.

Even though you stay clear of knotheads, simply bouncing along the roadway or path might induce the tennis ball’s location and SWR to shift. You’ll be able to put your SWR measuring device on the rack if you understand where it lives (the mark).

As we’re at it, remember that the antenna’s resonance response also receives significant impacts from the antennae tip. Therefore, it won’t work if you adjust the transmitter without the tip and then put it back on. The tip isn’t mandatory, but if you utilize it, ensure you perform all SWR readings having it on.

The process is pretty effortless. First, you record the readings and detach the tip afterward. Then, perform some adjustments before replacing the tip and rechecking. 

In addition, keep in mind that the shorter the transmitter, the more significant the variation in resonance frequency caused by the tip. If you damage the tip and need a temporary solution, tuning up the radio until you receive a new one is a brilliant idea.

Alternative Solutions For Tennis Balls On Antenna

Instead of using a tennis ball, you could use a few alternative items or methods to achieve the same benefits. 

The first one is other types of ball. Indeed, any ball, from basketball balls to football ones and even ping pong ones, can perform the same way as a tennis ball does. 

However, consider using a plexiglass sheet if you want to get rid of the weird combination at all costs. For the radio cable to go through, make a 1/2″ opening. 

For the opening’s reinforcement, place at least 1 inch of the plexiglass surrounding it. Finally, cushion the plexiglass between the tops and the bedside by getting the whip through the opening, and you’re good to go. 


Now you understand why tennis balls on antenna. Although the setting sometimes (or most of the time) looks super odd, it results in some beneficial outcomes. Yet, if you don’t know how to set things correctly, it could diminish your antenna performance. Thus, make sure to follow our guide strictly. Good luck! 

Further Reading