OTTAWA - Momin Khawaja personally outlined the workings of an electronic detonation device to the British-based leader of a terrorist bomb plot, the Ottawa software designer's trial has heard.

In a conversation recorded by the U.K. security service MI-5, Khawaja can be heard describing a transmitter, receiver and associated equipment to Omar Khyam during a visit to England in February 2004.

The discussion, played in court Thursday, touched on a variety of issues including the range of the device and its voltage requirements.

"All you need to do is this -- if you have detonator wires hooked up -- and that will send a charge down the line to whatever you're sending it to," Khawaja explained at one point.

The key allegation among seven terrorism-related charges faced by Khawaja is that he built a remote-controlled detonator for use in fertilizer-based bombs to be set off at a London nightclub, a shopping centre southeast of the city and electrical and gas distribution facilities.

The plot was discovered by British police and security forces before any damage could be done. Five men, including Khyam, were convicted by a British court last year and sentenced to life in prison for their roles in planning the attacks.

Khawaja, though named as a co-conspirator, was not tried with the others in London. Instead, he became the first person ever charged under Canada's Anti-Terrorism Act following his arrest by the RCMP in March 2004.

He has pleaded not guilty to all charges and is being tried without a jury by Justice Douglas Rutherford in Ontario Superior Court.

The technical discussions recorded by MI-5 on Feb. 20, 2004 weren't the only conversations bugged by the security service during Khawaja's three-day visit to Britain.

On another occasion Khawaja was heard assuring Khyam that it would be easy to pass his knowledge of electronics on to others.

"I can teach you the theory of it, cover all the facts and all these other bits," he said. "Then in the summer I'll set up a course together, someone can deliver it to the grunts of course."

In still other conversations, Khawaja reminisced about attending a training camp in northern Pakistan the previous year. He also showed his Canadian firearms licence to Shujah Mahood, Khyam's brother, and regaled him with stories of his target shooting exploits.

On another occasion, Khawaja endured a lecture from Khyam on clandestine tactics, including the need to maintain security and to follow the orders of cell leaders without question.

Khyam also counselled Khawaja to stay focused on the task at hand and not be distracted by irrelevant concerns. "Never mix things together, that's how you get caught."

The tapes played Thursday also reinforced a point made earlier in the trial -- that Khyam was in contact with Mohammed Siddiqui Khan, the leader of a separate plot that culminated in the July 2005 London transit bombings in which 52 bus and subway passengers died.

MI-5 recorded a discussion between Khyam and Khan in which the two discussed a range of issues, including travel to Pakistan and fraud schemes to finance terrorist activities.

Khawaja was not present for those discussions, however, and there has been no evidence that he and Khan ever had direct dealings -- only that they had a friendship with Khyam in common.

The recordings presented Thursday were the product of electronic bugs planted in Khyam's car and residence by British security officers. They also shot video and still photos of Khawaja arriving at London's Heathrow airport and being greeted by Khyam and his brother. The surveillance of all three men continued throughout Khawaja's visit.

At one point investigators tailed them to an Internet cafe where Khawaja showed his two friends web-based pictures of a device -- dubbed the Hi-Fi Digimonster -- that he had put together in the basement of his parents' home in the Ottawa suburb of Orleans.

It's that device, say federal prosecutors, that was intended for use as a bomb detonator but was seized instead by the RCMP in a raid on the family home in March 2004.

The Mounties also seized computers, firearms, ammunition, $10,000 in cash and books on Islamic ideology and terror tactics.