Mine Detector
 

Is there anyone out there who knows anything about mine detectors? I have recently purchased a complete one, but know very little about this type of equipment. Below are details from the unit itself and the outer box.
The outer box lid is marked:Detector Mine No4A Kits No1.
Stamped on the side of the box: FSA 1944
The detector itself has the following on a brass plate:Detectors.Mine.No4A ZA24238,Serial No 26153
Stencilled just above the brass plate it reads:Detector Mine No4A YA27932 WLH/5/50 Inside the box there is a 0-20" ruler with NoZA24871 stencilled on it.
There is also a test coil manufactured by GEC with ZA24870 stencilled on it.
Any advice will be greatfully received
Thanks
Keith