Abstract: An analyte recognition system uses an array (16) of ion-selective electrode (ISE) sensors, each sensitive to a different ion in a downstream flow path (32) therethrough to a coupling (30) which provides a ground or bias electrode. Another flow path (34) is upstream through an ISE sensor (26) which provides a reference electrode and the coupling. The coupling has a flow path, provided by a sidearm, to an outlet (40) going to a drain (35) for both the upstream and downstream flow paths. The upstream flow path reference electrode is a conduit for a reference fluid, and measurements from the other electrodes are made with respect to the reference electrode. Contamination and permanent poisoning of certain of the electrodes in the downstream path may occur if reversal of the flow were to take place, or if the reference fluid flowing in the upstream path were to flow into the downstream path.

Abstract: This invention relates to testing a coin by catching the coin, while it is moving, between a varying radius cam and a pin on a low inertia carrier. The carrier axle is in a fixed relationship to the cam. The coin's momentum plus weight turn the carrier until an end travel point is reached and momentum causes the coin to depart the carrier and go into an accept outlet. Additionally, magnetic fields passing through the coin's path provide further forces on the coin which help pull magnetic coins off the carrier into the reject outlet prior to the end travel point being reached. Undersize or underweight coins leave the carrier early and divert to reject. Oversize coins complete full travel, but cannot pass through to the accept outlet, and move back to reject outlet. Also, stringing of acceptable coins for retrieval is defeated by a trip in the accept outlet. Blockage of the reject outlet is defeated by a lever to stop rotation of the carrier in conjunction with a pin on the carrier to block spillover coins.