Dan-Pa. said:
...whatever happened to the tab, gold ring and nickle that sounded different ?
Dan, my post and link (that Dave linked) was about an earlier court case. The link I'd given in my post, was from 1981-ish. I do not know of any Tek vs Whites legal issues later in 1989 to '90.
As for your question of "tab, gold ring, and nickel" sounding different: There is no "smoke and mirrors" here. ANY TID machine of
any brand can do this. You can easily find a tab, a gold ring, and a nickel that .... when waved in front of a tone-ID machine, will each give a DIFFERENT sound . Since they hit at different places on the TID scale.
But that will do you nearly no good at all in field conditions. Ie.: you're not going to dig gold rings till your arms fall off, while effortlessly leaving junk and tabs and nickels behind. In other words, you will STILL dig a lot of junk. And you will STILL miss some gold rings, when electing to pass or dig various TID's.
The only thing that 3 objects at a table demonstration prove, is that *just* those 3 objects read at *just* those 3 sounds. It doesn't mean that all junk (tabs) therefore read/sound exactly like that. And that all gold rings (gold) read/sound exactly like that, etc....