“There’s a load of overpriced product, both eavesdropping and detection equipment, flooding the market,” the consultant says.
One of the biggest problems with any listening device is keeping it “alive” long enough.
“They run out of power. The bug is only as good as long as the battery lasts. A small [cheap] bug with a battery won’t last long. But some of the newer bugs can run up to three months on a single power supply.”
The cheaper bugs are “always on”, he says. You pay more for devices that only turn on when they detect voices or noise activated only bugs, or ones that can be programmed to listen at specific hours, or bugs that transmit recordings so you don’t have to physically go back and retrieve them.
As for the RF detecting devices, cheaper models will do the job but not necessarily well.
“They are not so easy to use correctly, and don’t tell the whole story,” the consultant says. “As an example, you need multiple — at least five, normally eight — different types of detectors to completely ‘sweep’ an area.
“Just ‘listening’ for a bug is not the solution; multiple searches, including physical searches, need to be completed.”
Detectors in an effective sweeping arsenal — not just an RF detector discount special — include spectrum analysers, infrared thermal imaging cameras (bugs emit heat due to their power source), telephone line analysers, radio frequency sniffers, and multiple frequency antennas.
“Small bug detectors can work, but it depends on the frequency range of the bug,” says the security analyst. “Listening devices work in frequencies, so in the home there is so much interference that it’s hard to pick up a bug.
“You’ve got your TV, microwave, mobile phones, tablets, baby monitors, Bluetooth devices; all receiving and emitting on different frequencies. You need to be able to scan and analyse up to 90GHz. The cheaper detectors won’t go much above 5GHz, if that.”
You also need to turn off all devices that broadcast radio signals, and turn off mains power.
But some listening devices won’t be found anyway.
“A small cheap digital recorder from Office Works can record for 24 hours, or longer, and won’t be found by a cheap bug detector as it’s not transmitting. But the problem is that it needs to be recovered, and often a lot of recording to go through to get anything of value.”
Another problem is GSM bugs, which are not easy to find, says Gerry Hall, director of security and debugging company I.P.S Overseas Ltd.
A GSM bug is a wireless listening device with a SIM card that can be activated by a telephone call.
“You will find many so called bug detectors and GSM detectors for sale online but they only detect when the bug is actually transmitting, and it will usually have a transmitting life of around three to six hours,” Hall says.
“The chance of the item actually transmitting at the time of the search is pretty minimal, so the user is led to the false conclusion there is nothing to worry about.”