Very well - at least one detector finds a coin by "electrostatic"-method and those 20cm are improvable.
However now I know that coins in air test will get more complicated as battery-sparks sensitivity tests.
But I don't know this is better if the new DC 2008 doesn't detect (any?) electrostatical-charges.
If you attach the Mineoro to some small parabolic satellite dish which is grounded with the box you may get better directional results.
I can imagine the pinpointing is complicated because of the broad and low frequency spectrum. So it works more like a:
"The nearer the signal-source, the stronger the waves."
However to construct and improve such devices it is very important those find metal - even with low sensitivity and very close - under "hobby-room conditions" and not only under "undisturbed far out in the fields or woods" ones.
btw. sparzed signals also can be the fault of a wrong designed end-stage. If the "give a blink or beep level" is too high you just will hear or see some "peak values". This is a question of threshold, filtering and making small changes of signal-power very good distinctable.
Thats's why some broadband analogue output could be better than just some on/off LEDs.
btw. the new ultrabright LEDs still work with a 1kOhm resistor using 9V (normally those work with 4.5 Volts and a pre-resistor of about 50-100Ohm) starting with 220 Ohm so it's possible to use them as very sensitive and from dark to bright going "analogue" signal-lamps.
OK, I really have now all information and will start with the "creative experiments". Yesterday I built already the accu-pack (8 x 1.2 or 1.5 Magnum) that has a 9V battery connector so the power is on!
First I will keep the circuits very simple but still trying to get maximum gain so almost everybody here can reproduce the effects. The more complex part will be a good "directional antenna" 'cause I guess just a small alu-tube won't receive much energy. Perhaps I'll find something between 90cm sat.dish and litte alutube.
I'm outta here but soon back and will inform you about the first tests including schematics and additonal stuff!