Abstract: A stylet 2 for stiffening a pliable infusion tube 38 comprising a wire 4 extending between a proximal and a distal end, a coiled spring 22 providing a flexible tip to the distal end of the stylet 2 for more easily feeding the stylet 2 through a convoluted infusion tube 38, a reduced diameter portion 26 of the coiled spring 22 telescoped over the distal end 20 of the wire 4 and bonded thereto, an enlarged end 32 of the coiled spring 22 for preventing the wire tip from exiting from the tube 38 through the tube wall or through openings 58, 60 in the tube 38, and a crimped coil 68 in the spring 22 for limiting the position of the distal end of the wire 4 in the spring 22, a connector 40 mounted on the tube proximal end, a bolus 50 mounted on the tube distal end, a connector 10 mounted on the proximal end of the wire 4, spring 22 being adapted to be seated in the bolus 50, wire 4 being longer than tube 38, whereby when proximal end connector 40 of the tube abuts the proximal end connector 10 of the wire 4, the bol

Abstract: This invention pertains to systems servicing coin operated telephones and, more specifically, to apparatus in such systems for preventing called party fraud in simulating coin deposit signals. During intermediate coin deposit periods, the network connection between the calling and called stations is split into calling and called portions and then these portions are extended and reconnected. A filter is inserted in the extended called station portion to attenuate fraudulent coin deposit signals originating from the called station. A coin tone detector connected to the extended calling station portion is still actuated by valid coin deposit signals from the calling station, but does not detect the attenuated fraudulent signals.