Abstract: A coin detecting device suitable for use in conjunction with a coin acceptor of a type employed in a gaming or vending machine comprises an inclined channel-shaped track which is formed from an insulating material and along which a coin may roll. Three flat metal plates are located on one side wall of the track, the plates being spaced apart in the direction of movement of the coin down the track and being separated from the coin by the (insulating material) wall of the track. The plates are spaced apart by a distance such that the coin will initially overlap first and second ones of the plates to form a first pair of series capacitors and, thereafter, will overlap the second and third plates to form a second pair of series capacitors. Voltage pulses are applied to the second (intermediate) plate and a detector circuit is connected in circuit with the first and third plates.