Great write up Kurrajong,
Found it very interesting how you touched on the human factors and peoples own personal belief sets with detecting. Its a mental game of chess where your opponent in the GOLD!
For example the fact that some people believe that the SDC can only find small gold. This belief is logically not valid. The real reason that the SDC seems to only find small gold is because no other detector in the last 30 years has been able to see it in the ground. People have been walking over the nuglets for 30+ years. The larger nuggets have mostly been pulled out of the ground, again an ADLI detector would have found the Hand of Faith.
So on the surface is would be easy to form a belief that the SDC is finding all these tiny pieces of gold and cant find a larger piece. That's because 30 years of detecting has depleted larger pieces.
When I first bought my SDC I had used it for about 8 full days in a month. Found nothing but rubbish. Was only about one or two trips away from selling it because all the "golds gone" that was my belief.
Then one day I found my first ever nugget. From that day forward my belief set changed to this thing really can find gold so slow down and scan the ground carefully and listen, or even better not listen too intensely and wait for that change in threshold. For the record I run mine on max settings. But have a "belief" that if I don't I will miss deeper or smaller pieces of gold. (I'm smart enough to realise this is most probably not true, but the brain is difficult to win an argument with)!
Some quirks I ve found is that if you do get a faint threshold change and rescan a few times, the sdc will balance it out and the signal disappears. Now I move the coil away from the target and have a few sweeps in a different spot then come back to the suspected target, if its there its something, if its gone, ground noise.
I learnt this when my 19yo was claiming he had a signal then he would say "no false alarm I m not sure now" He had headphones on so I could not tell. I did give advise earlier that if the signal is repeatable its something so stop and dig. I said give me a listen and then figured out what was happening. He then started finding small pieces that I did not hear on ground I have been over before several times, although the ground was very damp. Again a belief of mine is that it performs better in damp ground.
If it plays up badly, turn it on and off for a full reset.
Kind of use mine like a broom, sweeping forward and back trying to wear out the skid plate and slow.
Thanks for sharing your take on the wonderful SDC!
Cheers
RS