Gregory Craig Roberts, 44, pleaded guilty in Bendigo Magistrates Court yesterday to charges of possessing and using amphetamines, drug-driving, and failing to make a log book entry.

Prosecutor Leading Senior Constable Mark Snell told the court that on October 10 last year, Roberts, of Bethania in Queensland, was driving north along the Northern Highway at Heathcote.

Police pulled the vehicle over for a routine inspection, the court was told.

However, they soon shifted their focus because of the driver's appearance and demeanour.

The vehicle was being searched under the Road Safety Act, but this changed to a search under the Drugs, Poisons and Controlled Substances Act.

Senior Constable Snell said the driver soon admitted to police that he had earlier used amphetamines while at Somerton, north of Melbourne.

"The defendant then produced a small plastic press-seal bag containing a yellow substance, which had been hidden in the roof lining," Senior Constable Somerton said.

Nearly half a gram of amphetamines was found.

A drug test later found the presence of methylamphetamine in Roberts' system.

Magistrate Terry Wilson convicted Roberts on all counts, and fined him $800.

No order was made against his licence.