A Decepticon detector isn't a device in the animated portion of the Generation One continuity family.

Ain't no such thing as a Decepticon detector. You know that, and I know that, but...

Fiction[]

Cartoon continuity[]

When the Autobots were searching for Decepticons after they were scattered post-Unicron, they turned their eyes to Carbombya. President Fakkadi insisted that he harbored no Decepticons, but Outback and Blaster arrived to search his air force nonetheless. When Blaster lamented the difficulty in finding their quarry, Outback produced a device he claimed was a "Decepticon detector." Blaster expressed disbelief, and Outback admitted he was making it up. But when they were actually on the airfield, Outback announced that he had it and waved it around. Spooked, Dirge and Ramjet suddenly took off.

But Outback grounded them anyway, and they even gave him the location of Chaar. Maybe he told them he had a "Decepticon information extractor" too. Five Faces of Darkness, Part 1