Need some help I am new to this machine have run Whites all my 35 yrs of detecting. I am wonder how to set a threshold on this machine it tells me in the manual but can't seem to do it. I am used to the slight hum when I detect with my Whites. They say this is a top of the line for this machine but I am ready to toss it in the brook in my back yard. I would really appreciate some help from you pro's here on this site thanks.