Hey guys -
Sorry for the delay on replying to the thread... I'm having a really, really bad stretch of luck here, and my mind has been in overload for the past few days (let's just say that it may be difficult for me to get out and hunt for a while, seeing as it takes a vehicle to do so...)
Anyway, so, here's some of my thoughts - and I apologize if I'm repeating myself here... and bear with me - some of this info may be kinda jumbled up, but it's really the only way I can get it all down - stream of consciousness, yknow...
As far as hunting in trash, and determining whether to dig something or not - here's how I approach an "iffy" (or as I like to say, "funky") signal: Is it mostly a repeatable signal? if not, then, Does it hit solid in even one direction repeatedly? and, if not, then Does it pinpoint anything like a coin would? If any of these three apply, I dig the sucker... and then sometimes, I dig it just to learn what that particular sound is - to build up my "audio Rolodex", as it were... the gist here is that with the 66 you have to get "good" information from a "bad" signal - in other words, they are all good, until you determine they're not.
My experience has shown me that:
1. Objects (i.e. coins) will have a "range of depth" - in other words, if I lift the coil while pinpointing a signal which I believe to be deep and still hear a solid signal, say, 6" off the ground, I'm gonna guess that it could be something larger than a coin; if the object has a very "shallow" pinpoint signal, meaning it disappears after lifting the coil a couple of inches, then I feel pretty secure that the object is smaller than a coin (can slaw, pencil eraser, grommet, foil, etc. etc.)... the pinpointing of the 66 is one of it's best features - I can usually tell the depth of a coin by just the pinpoint signal alone...
2. Signals on the 66 usually have a "shape" to them... even though the 66 only has one "tone", there are countless variations on that tone, and they all mean something different. [Keep in mind these descriptions all depend on the depth of the object - deeper objects are harder to classify using the "shape" method.] Bottlecaps, for example, to me usually have sortof a "square" signal - a solid signal with hard edges. - kiondof a "bap bap" sound (I believe this has more to do with their mass than anything, but I may be wrong.) A shallow coin, however, will have a more "round" shape - still a solid signal, but with softer edges - more of a "waah waah" sound. Deeper objects will sound similar to surface objects, but they will be much "softer" - they will often be scratchy and seem like they're trying to discriminate, but it's just the coil trying to hang on to the signal... with that said, it comes back to the first criteria - repeatability and pinpointing. (And gut feeling.)
But to summarize all this, it really all comes down to knowing what it's trying to tell you (and it's going to try and tell you a lot), and the only way to figure that out is to listen to the signal, remember what that signal sounds like, dig it, and learn.