Silver Ring lying on cartboard detected from 15-20cm! over some sort of transformercoil I attached to the gate. Hum vanishes if ring is near.
So far no shielding and built on a plastic surface - no problem!
FET 2N5485 drain to antenna in (see schematic) and source to +9V via 150 Ohm resistor. Everything else like before.
Antenna- and fine-tuning-experiments will follow soon.
Thx for ya help Morgan and as you see already it also won't take very long to perfectionate the whole thing.
