No matter what you use, be it a TM 808,a Pulse Star, or any other large coiled, deep seeking metal detector,you are going to have to dig that deep. If your target is real deep,you might need a backhoe to do the job. Are you ready for that?
If you do not know how to field dowse or are not sure of your dowsing skill, here is how to avoid digging lots of empty holes for missed targets. I call it: Walking the string.
For this example, I am going to refer to the TM 808.
Buy or find four empty 5 gallon white plastic buckets. Many times you will see them lying empty on the sides of roads. A smaller bucket will do, but they need to be plastic.
The size of the area you want to search, determines the amount of string you will need. As an example for a 500 X 500 foot area buy 1000 feet of string from you nearest hardware store. A 1000 foot roll of string will cover many areas of interest and then some.
Go to the suspected treasure area.
Fill number one and number two buckets full of dirt to make them heavy and place them side by side on the ground.
Tie the end of your string to one bucket.
Unrolling the string as you go along,walk to and place buckets three and four 500 feet away from buckets one and two. Fill them full of dirt and place them side by side on the ground..
With your TM 808 turned on to scan, walk back to buckets one and two by following and unrolling the string as you go along.
Upon reaching buckets one and two, go around them and untie the string.
Follow the string back to buckets three and four, scanning and pulling the string as you go along.
Following the string you pull as you go back and forth over the area shows where you have scanned.
Each time you return to the buckets,move them sideways in the direction you want to go to cover the remaining target area.
No matter the size of your target area,you can cover every inch of it without scanning the same area twice,which can waste hours of time in a very large area..
Which is better, wasting time digging empty holes or spending time scanning every inch of an area and possibly finding your treasure? Of course, you may just find junk or nothing at all.