Another question:
Is it VERY common to get really good signals that turn out to be trash ?
All the trash I dug had good signals as I was trying to be somewhat picky instead of just digging everything
One TDI was a deep 38 and I thought YES !!!!
.....but it turned out to be a short piece of thick wire at about 7-8 inches
So the answer is yes and no.
Yes, you're going to dig signals that turn out to be trash. That's a given. The simple answer is that some trash signals cannot be differentiated between good signals.
The no part of this is on how MUCH trash you have to dig. This comes down to a few things. The quality of the machine you're using, the experience you have with the machine, and your own personal ability to 'learn' what the sounds and display are showing you actually mean in terms of what is in the earth.
I'm now in my 3rd year of using the AT Max, and my trash count is less than ever. It's not uncommon for me to come home with more good stuff in the pouch than trash. Some folks would call this "Cherry picking a site," but that's grossly inaccurate. It's not "Cherry picking" if you know it's trash! Cherry picking is choosing the best of the "good signals" (such as grabbing only quarters out of all the change signals, or looking only for strong silver signals, and leaving other 'iffy' signals in the ground). I don't cherry pick. If it's iffy, it comes out. But what is iffy has gone WAY down over the years.
I couldn't do this with my machine 2 years ago. I couldn't do it a year ago. I'll probably be even better next year...
What it comes down to is the nuances that the sounds make that distinguish trash from treasure. IF... (and this is a big IF) you are able to make out tiny little differences in the way wire sounds vs treasure, or foil vs rings, or garbage vs coins, you'll be more successful at weeding out trash.
To keep myself honest, most of what ends up in my pouch is me predicting what it's going to be and then checking periodically during the hunt. I usually dig up the first 10 or so items no matter what they are (unless it is obviously trash), just to ensure my skills are sharp. I'll call it out in my head before it comes out.
Things like, 'Squished pencil topper (ferrul)', can slaw, aluminum fence wire, gum wrapper... all get named before I pull them out. I'm always trying to hone in on exactly what the items is. Then, after digging enough of them correctly, you can start to figure out what makes a signal 'off' from the normal ones. Sometimes, its not even quantifiable in terms of describing the signal sound.
"It just didn't sound right, so I dug it." is a common theme for me. Also common is, "I don't know what that is."
Bottom line is,
"when it doubt, it comes out."
And, as I said, 2 years ago, a LOT came out. I put 400-500 hours on my machine every year. That's part of what keeps my ears sharp. And every year, I have two "dips" in my ability to find things. When I switch from cuffed earphones to earbuds in the summer, and then back again in the fall. Both those events cause me to have to re-learn a little bit, and my trash finds go up.
Bottom line here, is that you CAN get more out of your machine. I've got over 1000 hours on mine, and I'm still squeeking out more and more good finds vs. trash. And when you can avoid digging something, you automatically save time for more swinging for good stuff.
To be clear, I'm not out here trying to win a competition. I just am trying to be the best MD'er I can be with my machine. I don't want to waste my own effort digging up trash. That's lame. LOL
Skippy