AUTONEWS

The trick that turns your head into an antenna for your car remote control

Sometimes, forgetfulness plays tricks on us. You return to the parking lot where you left your car and can't remember where it is. You press the remote control, looking for flashing lights, but perhaps it's too far away and the signal doesn't reach you. What this driver may not know is that there's an incredible trick that allows you to extend the range of your remote control using something we all carry with us (literally): our own head. It may seem like science fiction (or something out of a MacGyver movie), but your skull can act as an improvised antenna that increases the range of your remote control, perhaps even making the lights you're looking for turn on.

The method is simple and only requires placing the car remote control near your temple or under your chin, pointing it at the area where you think the car might be, and then pressing the lock or unlock button. We're not suggesting you perform magic, but rather that you take advantage of the properties of physics. This is because the human body, composed mainly of water, acts as a natural conductor of electromagnetic waves. By placing the remote control close to your head, you create a kind of resonant cavity that allows the low-frequency radio waves used by car remote controls to be amplified before being emitted into the air.

Body resonance...The effect even has its own name: "body resonance." This resonance allows the skull and cerebrospinal fluid, rich in electrolytes, to conduct electricity when an electromagnetic field is present. The radio signal from the key, upon reaching this structure, is amplified in a specific direction.

Electrical engineer and science communicator Kyle Hill has explained this principle on several occasions, noting that the head acts as a radio frequency signal amplifier. This allows the waves to travel with greater intensity and overcome obstacles that would normally prevent them from reaching the area.

However, it seems that the effectiveness of this trick varies from person to person, as it depends on factors such as the bone density of the skull, the amount of body fluids, and the specific operating frequency of each car's remote control. And, in any case, don't expect a significant increase: under normal conditions, the range of a modern car remote control ranges between 50 and 100 meters, and by holding it close to your head, you only gain about 10 or 15 meters.

Furthermore, it has been proven that if you slightly open your mouth while pressing the remote control attached to your chin (this all sounds like a joke, but it's true), the effect is even more amplified, since the oral cavity also plays a role in resonance and sends the signal even further.

This curious trick, however, has its limitations. It never replaces dead batteries. Nor does it transform a simple key into a long-range remote control. Its true usefulness becomes evident in critical situations, when you've strayed far enough away to lose the signal, but not far enough to make the walk back (if you're unsure whether you locked the car or not) unpleasant. And, interestingly, it's still surprising when you realize it actually works.

Holding your car remote (key fob) against your head can significantly increase its effective range, sometimes doubling it, by using your skull and bodily fluids as a rudimentary antenna. This technique, often demonstrated to help find a car in a crowded parking lot, works because of the high water content in the human body (around 73%). 

How the trick works:

Capacitive Coupling: When you press the key fob to your head (temple or chin), you are "capacitively coupling" the device to your body.

The "Antenna" Effect: The fluids in your skull act as a conductor, essentially extending the antenna of the remote and amplifying the signal.

Dielectric Resonator: The water in your head interacts with the electromagnetic waves from the remote, acting as a "dielectric resonator" that increases the amplitude of the signal.

Better Directivity: The human body acts as a reflector, helping to focus or direct the radio waves toward the car, rather than letting them dissipate in all directions. 

Effective methods:

Under the Chin: Pressing the fob directly under your chin and opening your mouth slightly can be very effective.

The Temple: Pressing it against the side of your head (temple) is another recommended spot.

Height Matters: Even without touching your head, simply holding the remote as high as possible increases range because it reduces obstacles between you and the car. 

by Autonews