What we have here is 4 inches of 26 ga. wire.  Antenna is tapped on the ground side every every 6 turns.  The detector is tapped every 10 turns on the high side.  The rotary switch you see selects the detector.  Currently, I have a dbl 1n34A in position 1, a single 1n34A in pos. 2, a BAT 46 in pos. 3 and a galena crystal in pos. 4.  Position one works great for strong stations... Position 2 is the usual operating position.  The BAT 46 is experimental... works okay, and the Galena  is used for  kicks and giggles.. A 100K resistor and a .01 cap are across the crystal ear piece..