Agra GPS, the Edmonton-based maker of “bridge” kits that allow John Deere Autotrac to work in autosteer-ready tractors of any brand, has turned its attention to guidance receivers.

The roof-mounted CRG box is fully compatible with Deere’s GPS system.

It attaches to the same roof brackets and plugs into Greenstar monitors just like any Starfire 3000, 6000 or 7000 receiver.

See also: UK made kit converts any tractor to RTK autosteer for £3k

It works using industry-standard correction signals, either from a wi-fi connected base station or a mobile Ntrip network.

Opting for the former eliminates all ongoing costs, but means shelling out more dosh upfront.

The Emlid version offered by Agra GPS is priced at C$3,650 (£2,050).

This includes free Ntrip caster accounts for up to 10 CRG receivers.

This provides sub-2cm accuracy to across 10km, after which it will diminish by about 1cm for every further 10km the machine travels.

Alternatively, buyers can tap into a mobile Ntrip system.

For the most reliable service, the company suggests using an open-network SIM card that will pick up a signal from any nearby mast.

Cheap data

The data itself is cheap – £150 will get 20GB of cellular data, which should last the best part of a decade.

An Ntrip subscription in the UK typically costs £450-£800 a year.

The other option is to tether the system to the operator’s mobile phone via Bluetooth.

However, this relies on a decent network connection across all fields.

The CRG receiver costs C$5,650 (£3,175).

It is possible to get one complete with the Agra GPS bridge kit, so it can be set up on any autosteer-ready machine.

It will also work with Deere’s Operations Center for work documentation and the like.

However, it doesn’t unlock paid-for features in the John Deere monitor, such as Autotrac and section control.