Stuart II problem

[VUJO]

I have built Stuart II detector,but I can onley detect metal objects and Aluminium.Could anyone tell me what to do

[WM6]

?

Vujo do you want to detect wood and plastic object too?
Its name is metal detector, what is wrong with yor detecting? Probably nothing, all is ok.

[VUJO]

I have made some mistake I should wrote FERUM,not metal.