I have a gti 1500 just got it so i'm having a learning curve.i am new at this hole thing.I was out at a old park goes back to early 1800.I had several indications of a coin down 4-6 inches dug down8" found nothing.if a coin is old how far down would it be.the ground is very dry at the site. would that make the depth range not accurate?I only have about 10 hour experiance but i have found some coins nothing old.if anyone can help i would appreciate it. thanks mham2