Bugging case: Listening device discovered by All Blacks 'cheap' and 'poor quality'

The listening device discovered by the All Blacks' security consultant was "cheap" with a weak transmission signal, says a bugging specialist.

And a police test recreation this year showed the frequency emitted from the "poor quality" device, discovered by Adrian Gard ahead of the Bledisloe Cup test last year, was not picked up when the room was first swept.

Gard has pleaded not guilty to one charge of a false representation to police leading to an investigation. The evidence is being heard over two days at the Downing Centre Local Court in Sydney.

The original sweep by Charles Carter, the owner of the Bug Sweepers, found electronic "alerts" on two chairs, which he suggested Gard should cut open to make sure.

He warned that particular test, looking for silicon in semiconductors in electronic devices, could bring "false positives" when furniture was scanned.

However, with a different device, Carter also created a "signal list" of all the frequencies in the room where he tested the chairs on August 15, 2016.

As Carter left the hotel, Gard took the chairs to his room. He latercalled All Blacks manager Darren Shand after a device was found in one of the chairs.

"The chair that was closest to me I could see the foam of the chair, what looked like a battery and wires still in the chair, wire running along top of the foam," Shand told the court earlier in the hearing.

"I don't recall exact words, my recollection is, 'what is that?' Basically both of us staring in shock...the realization it was some sort of listening device."

When the police recreated the "signal list" test with Carter, this time using the bug which Gard said he found in the chair, the frequency emitted by the device created a sharp spike.

However, this peak did not exist on the original "signal list" Carter created on the day when he originally scanned the hotel room.

In the video recreation, Detective Sergeant Paul Mangan asked if Carter would have been suspicious if he had seen the spike on the "signal list" and investigated further.

"Yes," said Carter on the reconstruction.

"That signal, from the device, is getting a read, which is not on the original signal list?" asked Mangan.

"Yes," said Carter.

He also said the strength of transmission from the device dropped after a distance of only five or six metres, which meant an audio captured would have been of very poor quality.

"It's a very cheap bug, probably $50, the quality is very poor," said Carter on the video.

"Which someone would have known if they tested it. Someone has gone to a lot of trouble to put in a poor listening device, with a poor transmitter."

Under cross-examination by Gard's lawyer Anthony Kimmins, Carter confirmed he said the chairs were "very suspect" and Gard should remove them as a "bare minimum".

He also confirmed the frequency of the bug would not be on the "signal list" if the device was not transmitting, for example if it was not connected to the battery, or the battery was flat.

The cross-examination of Carter will continue on the second day of the hearing.