My F70, now two years old
Clad Penny 57 to 67 depending on depth -- a lot of the newer pennies sound off at 57
Copper Penny 68-71 sound off like dimes
Clad Dime 67-68
Nickles 28-33 depending on depth
Sliver Dime 69-71
Clad Quarter 81-83
Silver Quarter 87-90
Clad Half 87-90
Silver Half 87-90 @ 8" I found two of these both at *'8 each two weeks apart and they read a steady 87, like a rusty steel bottle cap. So, I have never found any walking halves before or since
Clad Dollar 99 solid -- I have yet to find a silver dollar. This Clad was only 1" under -- almost did not dig it cause this is the same reading I get for large chunks of trash
Old rusty bottle cap buried 1-4" -- 87
Shiny new bottle cap on surface -- 87
Aluminum soda can or beer can buried 6" or more -- 10-11" even -- reads like a silver dime. Who is burying aluminum beer cans? Under age people out on the park after hours !!!!
Aluminum tabs 26
Aluminum slaw 24-31
Even with TAB disc out I get hits on them -- I avoid most bottle caps by a fast swing rate -- in fact the Fisher F70 likes a fast movement and read really well as opposed to a slow easy swing rate. In fact, you can actually move slow enough that it will not read a target. Try it, take a coin and move it slowly about 3" from the face of your coil. Now try to move the coin as fast as you can and you will see. The Fisher return signal and readout is fast, really fast and it like it faster. In this fast swing method most bottle caps get phased out but if one reads and you slow down to concentrate on the signal it will start reading like a strong Quarter -- A real Quarter, on the other hand will read -- sound off loud and clear at both fast and moderate swing speeds. Still, when it sends a signal to your ears it is up to you to dig or not. This has been my experience with my particular F70 with the DD 11" coil and the smaller Nel Sharp shooter.
The readings I have just listed are consistent on my F70. -- On the depth meter I have found that anything within 3" of the coil will read a 3" depth -- no one in a park with grass is running their coil flat on the ground. So, if I am swinging 2" over the dirt and get a 3" reading then the target is somewhere from the bottom of my coil to the target up to 3" into the dirt. If I get a reading of 3" and the target is not there then it is most like a Pipe, drainage, or otherwise maybe up to 12" or more down. So, if your F70 says 3" it means within that range or it is something much deeper. If, however, it reads 10" within the desired target ID range then you had better dig it. When the F70 is reading beyond the 3" range it is spot on in depth. But again, if you dig to the depth it reads and find nothing it is most likely something much much deeper, like an old car body -- ha, ha. Now I know why relic hunters carry shovels.
I have more than paid for all of my equipment (couple of times over) these last two years. I have turned up some 40 rings of value -- four of which are gold, and another 30+ rings of little or no value, like kids rings. In case any tax guys are listening in -- this does not take into account the miles driven, the gas and other incidentals like my occasion cigar -- Keeps the mosquitoes away -- and the Star Bucks coffee to wake up for the morning hunt. I figure all totaled it is about even. But I enjoy those cool mornings as the sun comes up and I see the geese flying over and the pit bull racing across the ball field, straight for me -- great hobby and I love it. Peace and I hope this little blurb helps or increases the knowledge of any newbe out there -- I was you once, wet behind the ears cause my headphones made me sweat so -- now get out there and work, work, work, and stop digging such big holes, leave the shovel at home, with the F70-75 you should be able to pinpoint your target within an 1" or 2 and with a pin pointer you are done, if you are digging those hug holes like we see some are doing on You Tube then you have the wrong machine, period. Peace Dan