The tell-tale widgit supplied by Tracker led the Surrey officers to an isolated property while they were patrolling the M25.
They discovered the JCB and other stolen property as well as a hydroponics drug factory.
Tracker, which recently launched a battery-powered stolen-vehicle recovery (SVR) device, said its figures showed 68% of all plant recovered was done so within 24 hours of the kit being activated.
Users could hide transmitters on large mowers, trucks, trailers, dumpers and excavators. Unlike other tracking systems the device worked even if the missing kit was taken abroad, said Adrian Davenport, regional police liaison manager at Tracker.
"Around £50m to £70m worth of machinery is stolen every year, of which just five% is ever recovered. Fitting a tracking device can significantly increase the chances of stolen equipment being located by police and returned."