Back-up-beeper


Posted on Feb 22, 2013

Put the car in reverse and the circuit provides a loud, audible beep at the rate of about one per second (1Hz). Half of U1, a 556 dual oscillator/timer, is used as a slow-pulse oscillator with a rate of about 1Hz. Components R2, R1, and C1 form the long time constant. You can calculate on time by t~.7 (R1 + R2) C1 or 1.15 seconds. The off time is shorter than the on time, at . 77 second. Enabling pin 4 (reset) is held high to keep the oscillator freerunning when voltage is applied to pin 14.


Back-up-beeper
Click here to download the full size of the above Circuit.

The output at pin 5 is coupled to pin 10 of U1 enabling oscillator 2. Oscillator 2 of U1 produces an audio output of about 1 kHz, as determined by C2, R3, and R4. Pin 10 (reset) of oscillator 2 is connected to the pin 5 output of oscillator 1. Sn when pin 5 becomes positive, the oscillator beeps a short pulsed tone of 1 kHz.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

AM Radio
MOSFET Headphone amplifier
3w fm transmitter
radio circuit diagram
16 step sequencer schematic
89 S10 Starter wiring Snafu
Vu meter stereo circuit
Henry Radio 5K Classic Blower Modifications
Receiver schematic design using MC3335PSSB
A hi-fi amp around 01



Top