A dual-mode alarm apparatus for a ski having a generally flat narrow upper surface mounted with a ski binding for receiving a skier's ski boot, the dual-mode alarm apparatus comprising:
- a. a unitary housing having an aerodynamic exterior configuration;
- b. said housing retaining an auditory alarm means, a visual alarm means, a power means, a power switch, a tether switch and a motion sensor, all electrically connected with electronic alarm circuitry contained within said housing;
- c. said auditory alarm means being able to produce an audible alarm which can be heard from outside of said housing;
- d. said visual alarm means being able to produce a visible alarm which can be seen from outside of said housing;
- e. said power switch being switchable from outside of said housing by a key means, such that said alarm circuitry is electrically energized when said power switch is switched to an on position, and said alarm circuitry is electrically de-energized when said power switch is switched to an off position;
- f. said tether switch having a tether aperture accessible from outside of said housing for accommodating a tether means, such that the insertion of the tether means causes said tether switch to be in a closed status and the removal of the tether means causes said tether switch to be in an open status;
- g. means for mounting said housing onto said generally flat narrow upper surface of said ski at a location adjacent to said ski binding;
- h. means for linking said tether means with said skier's ski boot such that the separation of said skier's ski boot from said ski binding will cause said tether means to be removed from said tether aperture of said tether switch;
- i. said alarm circuitry including a visual alarm driver for operating said visual alarm means such that when said power switch is switched to said on position, said visual alarm means will produce said visible alarm;
- j. said alarm circuitry further including an initialization circuit and a flip-flop array for setting said alarm apparatus in one of two operating modes including a tether detect mode and a motion detect mode, such that when said tether switch is in said closed status, switching said power switch to said on position will set said alarm apparatus in the tether detect mode, and when said tether switch is in said open status, switching said power switch to said on position will set said alarm apparatus in the motion detect mode;
- k. said alarm circuitry further including a logic gate array connected to said flip-flop array and said tether switch and being operable in both said two operating modes;
- l. said alarm circuitry further including an auditory alarm driver connected to said logic gate array for operating said auditory alarm means, such that said auditory alarm driver will cause said auditory alarm means to produce said audible alarm upon receiving a desired logic output from said logic gate array;
- m. said logic gate array including logic gate means which will produce said desired logic output, when said alarm apparatus is in said tether detect mode and the status of said tether switch is changed from said closed status to said open status;
- n. said alarm circuitry further including a counter means interconnected between said motion sensor and said flip-flop array for causing said flip-flop array to produce a desired flip-flop output which in turn will cause said logic gate array to produce said desired logic output, when said alarm apparatus is in said motion detect mode and said motion sensor detects movement of said ski;
- o. said flip-flop array will not produce said desired flip-flop output as said motion sensor detects movement of said ski, when said alarm apparatus is in said tether detect mode;
- and
- p. said logic gate array will not produce said desired logic output as said tether means is removed from said tether aperture of said tether switch, when said alarm apparatus is in said motion detect mode;
- q. whereby when said skier is going to use said ski for skiing, said skier can first insert said tether means into said tether aperture of said tether switch and then turn said power switch to said on position to set said alarm apparatus in said tether detect mode, so that said audible alarm will be produced upon the separation of said ski binding and said skier's ski boot for assisting said skier to locate said ski, and when said skier is going to leave said ski unattended, said skier can first remove said tether means from said tether aperture of said tether switch and then turn said power switch to said on position to set said alarm apparatus in said motion detect mode, so that said audible alarm will be produced upon the unwanted movement of said ski for alerting said skier to guard said ski.