Patents
Patents for G04C 21 - Producing acoustic time signals by electrical means (1,026)
04/1977
04/05/1977US4015417 Alarm time setting notifying mechanism for a clock or the like
01/1977
01/25/1977US4004408 Mechanical improvement on an electric alarm clock
12/1976
12/28/1976US4000384 Unlocking mechanism
12/21/1976US3998045 Talking solid state timepiece
12/14/1976US3996734 Minute-interval alarming device for a clock or the like
09/1976
09/28/1976USRE28985 Alarm clock timer with manually operable reset mechanism
09/21/1976US3981139 Self contained battery operated clock fabricated on a single printed circuit board
08/1976
08/31/1976US3978296 Switching system for an electronic timepiece
08/31/1976US3977291 Attenuator network for musical instrument keying system
08/31/1976US3977177 Electric alarm watch
08/24/1976US3975896 Switching device for electronic timepiece
07/1976
07/27/1976US3971207 Packing means for a watch
07/13/1976US3968900 Timed medicant dispensing device
06/1976
06/29/1976US3967078 Time switch mechanism
06/01/1976US3961327 Audible alarm for a synchronous motor
05/1976
05/11/1976US3956597 Speaking time keeper
05/04/1976US3953965 Digital clock
04/1976
04/20/1976US3952177 Timer for multi-purpose use
04/06/1976US3949240 Switching circuit for power supply to electronic apparatus
03/1976
03/23/1976US3946314 Remote control programming system
03/16/1976US3943700 Large-sized clockwork with an electrically driven striking train
02/1976
02/10/1976US3938047 Control circuit for use with amplifier
01/1976
01/20/1976US3934120 Device for electroconductive connection and reading
01/06/1976US3931621 Variable amplitude timed alarm system
01/06/1976US3930360 Alarm clock timer
01/06/1976US3930358 Alarm clock timer
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