99.99% of the time, they're going to be large junk. Like a hubcap, a flattened can, a pipe, a chunk of caste-iron, etc... The odds of any of them being a cache, is going to be pretty slim.
Oddly, back in the 1960s and early 1970s, there were probably more caches found per capita of users, than there is today. Even though our modern sophisticated sensitive machines are deeper seeking than yester-year machine, yet more caches were found in those days, of the cheapo BFO and all-metal TR's. The reason is simple: by their very definition, they were insensitive to smaller objects (some could only get a coin to an inch or two) yet could get larger objects with ease. So a person hunting a ghost town or whatever, had the "perfect discriminator" for those pesky small objects (coin, tabs, etc...), yet could still get jar sized targets.
Sometimes, when working demolition sites, or relicky sites, I'll dig up the overload signals just to get them out of my way (check for things next to or underneath, that were masked), NOT because I'm anticipating anything good from the overload signal itself.
I'm sure that over the years, many md'rs have passed up a jar or box of coins that gave an over-load signal, because they figured they were going to pass "another hubcap"
Has anyone had any good finds on digging overload signals? I dig them at times just out of curiosity. Would like to hear your thoughts or stories on the subject.
Happy hunting to you all.