994, 736. Coin testing. TATEISI DENKI KABUSHIKI KAISHA. Nov. 15, 1963 [Nov. 27, 1962(2); Nov. 28, 1962; March 22, 1963], No. 45129/63. Heading G1N. [Also in Divisions G4 and H2] During their passage down a shoot coins are connected as one electrode of a capacitor the capacity of which is measured to indicate the nature of the coin. Where, as in Fig. 1, a coin 2 in a shoot 1 slides over a ceramic base 4 with a back electrode 5 contact being made with the coin by an arm 9 and roller 10, the capacity depends on the area of the coin and the spacing of the coin face from the base by the coin rim. The coin may pass between two opposed insulator-electrode arrangements, such as 4, 5, so as to provide a third electrode and form two capacitors either in series or parallel. With such an arrangement the thickness of the coin is a factor affecting the capacity measured. The nature of the material of the coin may also be involved in the measurement if the capacitor is connected into the resonant circuit of an oscillator which is designed to discriminate between Q-factors above or below a given standard. If the circuit oscillates this may be taken to indicate a coin which gives a Q-factor higher than that to be expected and the coin can be rejected on this advice. A delay is introduced between detection and rejection to allow the coin time to reach a trap 6 which reflects to solenoid 13 to drop the coin into reject shoot 1<SP>11</SP>. Figs. 7 and 8 show arrangements alternative to the roller contact 8, 9, 10 of Fig. 1. In both illustrations the contact 53, or 64, is vibrated so that the coin progresses over the ceramic base in a series of steps.