Which one of the three would be best on dry beach sand?
All with standard coil.
1. Old Tesoro Diablo-2 Gold Demon (20 khz). Gnd Adj, Sensitivity, Threshold. No discrimination capability
2. Old Tesoro Silver Sabre Umax (10 khz).
3. Old Fisher 1235X (5.7 khz).
4. New Fisher F22 (7.5 khz).