Position: Index > Electrical Circuit >

Star Trek Doorbell

2014-11-29 11:37  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.


Star Trek Doorbell
In the Star Trek ?Next Generation? TV series, the doorbell outside the private quarters of a crew member makes a particular ?beep-boop? sound. The 3v battery powered circuit below tries to simulate this sound. The circuit uses one 74HCT74 dual D flip/flop IC, wired as two one-shot circuits. Both are designed to produce a pulse about one half second long. The first pulse turns on a 555 timer to form the beep sound. Source: discovercircuits