Fri | Sep 22, 2017

Devices within same range conflict

Published:Sunday | February 21, 2016 | 2:00 AM
The key fob of a motor vehicle equipped with a smart system.
A radio transmission tower.
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Technology is constantly advancing and, with that, has come the marvel and immediacy of the Internet, consumer 'tech' such as smartphones and, of course, remote entry and push-button engine start/stop automobiles.

A common element is the utilisation of electronic frequency, which allows technology users to connect their gadgets live streaming from the Internet, instant messaging, accessing radio and television broadcasts. And even starting a car engine at the push of a button.

A representative at the Spectrum Management Authority (SMA), national regulator for the radio frequency spectrum, told Automotives that even the key remotes used to lock and unlock car doors are operated on a specific electronic frequency.

"The frequency (that these remotes work on) is typically 433 MHz. There is a transmitter in the key (remote) that sends the signal to a receiver in the vehicle. This receiver in the vehicle is connected to a coil. So when the receiver gets the signal it energises the coil which, in turn, causes the doors to open," Mahlangu Lawson, telecommunications engineer, SMA, said.

Lawson said where remotes are used to start vehicle engines which have keyless, push-start ignitions, if different devices operating on a similar frequency range are in the same area one can obstruct the other and cause a malfunction. He told Automotives that though interference is a common cause of malfunction for devices such as remotes (for car engines, garage doors, etc), technology users' first instinct is usually to check if the device's battery has died.

Following are a number of commonly used devices and the electronic frequencies they operate on:

Car Remotes

Frequency

315 MHz or 433.92 MHz typically.

Comments from SMA

Frequency depends on the vehicle manufacturer.

Radio Towers

Frequency

88-108 MHz, 947-960 MHz and 310-328.6 MHz

Comments from SMA

Frequency depends on its use. The frequencies the public hear are referred to as broadcast frequencies, (88-108 MHz). The other two bands are referred to as Studio to Transmitter link frequencies.

Cell Phone Towers

Frequency

699-806 MHz, 842-849 MHz, 869-894 MHz, 892-915 MHz, 925-947 MHz, 1722-1755 MHz, 1817-1850 MHz, 1850-1910 MHz, 1930-1990 MHz, 1710-1770 MHz, 2110-2170 MHz, 2500-2690 MHz, 3400-3600 MHz

Garage Remotes

Frequency

Same as car remotes

Comments from SMA

Frequency depends on the manufacturer of the garage door opener.

Microwave Ovens

Frequency

2450 MHz, 915 MHz

Comments from SMA

Frequency depends on the type of microwave. That is, consumer or industrial.

Wi-Fi Access Points

Frequency

Mainly 2402-2483.5 MHz and 57255875 MHz

Comments from SMA

Frequency depends on the type of access point.

Cordless Phones

Frequency

902-928 MHz, 2402-2483.5 MHz, 57255875 MHz

Comments from SMA

The frequency used depends on the manufacturer of the device.

davion.smith@gleanerjm.com