I work on the railway and came across this in a hedge bottom. Apparently it's some sort of GPS device for combine harvesters etc? Called a John Deere Starfire 3000. Looked on ebay and they seem to be worth a fair bit. It's in near perfect condition except a little rust on the screws underneath..
 
	Any idea how I can find out if it works other than plugging it into a combine harvester which unfortunately I don't own..
 
	Thanks, 
 
	Sam.