Radio-controlled alarm clock with digital and symbolic displays

摘要

The clock has conventional hands (11) rotating in front of a dial (12), and also a digital display (19) linked to a register (24) in which the set time is stored for comparison (25) with the content of a time-of-day register (26) corrected by signals from a radio receiver (21). A portion (15) of the display carries an alarm-bell symbol (17) which appears continuously in the alarm mode, flashes while th alarm circuit is in a SET mode, and is extinguished when the alarm is inoperative. The SET mode is established by simultaneous operation of two key switches (18,20) whose outputs are AND-gated (23) to a holding circuit (30).