Brisbane police involved in G20 duties will use secure digital communications while their Gold Coast counterparts make do with analog.

Queensland’s police union says its members are at risk from eavesdropping criminals until the analog radio system is completely upgraded.

The state government has pledged more than $500 million over 10 years to change police radio to a more secure digital signal across Queensland.

Police in Brisbane have already made the switch and officers involved in G20 duties will use the digital signal during the leaders summit in November.

But a spokesman for Police Minister Jack Dempsey told AAP the wider introduction for southeast Queensland would not happen until 2015.

Until that time, the Queensland Police Union says officers using the analog signal could be intercepted by scanners, meaning criminals could potentially track police movements.

President Ian Leavers said the signal could also be intercepted by anyone with a smartphone.

“Therefore, it puts everyone at risk and the information is public information,” he told reporters in Brisbane on Tuesday.

“(Information) needs to go, when it’s very highly sensitive, directly to police.”

Mr Leavers said he was also concerned about resourcing shortfalls, which included a lack of protective body armour and Tasers for officers after the terrorist group Islamic State released a propaganda video mentioning Australian authorities.

He said a more secure system would allow officers to share information about suspects within seconds.

“We just need the equipment to do the job. Police simply are being left out in the cold and they are expendable, that is the way police feel,” Me Leavers said.

Premier Campbell Newman was not able to say when the digital technology would be available on the Gold Coast and parts of Logan, south of Brisbane.

“This government inherited a situation where the police had a communications network that essentially the criminals could listen in to,” he said.

Police Commissioner Ian Stewart said the state government had made a “huge investment” in the new system and its benefits were not restricted to security.

“The digital network allows us to through its ability to link up what they call ‘talk groups’,” he said.

“It means that we can have officers raiding a place or doing a job in Cairns, with someone in Coolangatta listening in to that job, if they’re given access.”

The analog signal would not be dropped completely, Mr Stewart said.

“Analog has served us very, very well for many years. It’s a great backup tool.”