"Farm GPS theft" actually covers two very different crimes, and it's worth being clear which is which — because the protection is completely different, and so is the question of whether an RF engineer can help. One is thieves stealing the GPS kit itself. The other is jammers used to steal whole machines. Here's the honest version of both.
Problem one: stealing the GPS kit itself
This is the big one, and it's everywhere in the farming press. Thieves break into cabs and physically rip out the GPS receivers, domes and screens — units worth well over £10,000 each — to sell on, often abroad. It's portable, high-value and in demand, which is why organised gangs hit several farms in a night and come back for the replacements weeks later. Insurance claims for it have run into the millions.
Be straight about this: an RF engineer can't help much with kit theft. That's a physical-security and forensic-marking problem, and the people to listen to are your rural insurer and the rural crime teams. The standard advice holds — remove and lock away units where you safely can, activate PIN protection, record serial numbers, and forensically mark the kit so it's harder to resell. If your worry is the GPS gear being stolen off the tractor, that's the route, and it isn't something detection equipment solves.
Problem two: jammers used to steal the whole machine
This is the one that is an RF problem. A GPS jammer that plugs into a 12V socket costs around £30 and floods the satellite band so any tracker fitted to the machine goes blind. Switch it on, and a tractor, telehandler, quad or loader can be driven or trailered away with no live trace for the tracker to follow. It's the same technique used to steal cars and plant — and farm machinery is squarely on the list. If you rely on a tracker to protect a high-value machine, a jammer is the thing designed to defeat it.
How to tell which you're dealing with
The distinction is usually obvious once you know to look for it. Kit theft leaves physical evidence — a smashed cab, cut wires, a missing receiver. Jamming leaves the machine intact but the tracking goes dark: an asset that simply vanishes from the system, or several machines losing signal at once in the same yard. If the kit's still there but the tracker stopped reporting, think jamming. If the kit's gone, that's the other problem.
Two problems, two answers
Worried about the GPS units being stolen off machines? That's physical security and marking — talk to your insurer and rural crime team. Worried about a jammer blinding the tracker so a whole machine disappears? That's the RF side, and it can be detected, located and proven.
See GPS jammer detection →What detection actually does for a farm
On the jamming side, detection gives a farm the same things it gives a plant yard or a fleet. It tells you the moment GPS is being jammed in the yard, rather than after a machine's already gone. It lets an engineer locate an active jammer — a device on a vehicle that shouldn't be there. And it produces independent, documented proof that jamming occurred, which matters for an insurance claim. None of that recovers a stolen GPS receiver, but all of it bears directly on the machines a jammer is used to take.
Detection only — and lawful
One thing worth stating plainly: using or supplying a jammer is a criminal offence in the UK. Everything here is the defensive opposite — detecting, locating and documenting jamming, never producing it. If a jammer turns up on your land, it's evidence; leave it be and get it documented properly.
Where this leaves you
For most farms the sensible picture is layered: physical security and marking to deal with kit theft, and detection to deal with the jamming that's used to take whole machines. If it's the second you're worried about — trackers going dark, machines disappearing despite being fitted — that's the part worth an RF investigation.