Speed alarm

Posted on Mar 23, 2013

Pulses from the distributor points are passed through a current limiting resistor, rectified, and clipped at 4 volts. Via Q1 and the diode pump, a dc voltage proportional to engine rpm is presented to RV1; the sharp transfer characteristic of a CMOS gate, assisted by feedback, is used to enable the oscillator formed by the remaining half of the 4011

Speed alarm
Click here to download the full size of the above Circuit.

At the pre-set speed, a nonignorable tone emits from the speaker, and disappears as soon as the speed drops by three or four mph.

Leave Comment

characters left:

New Circuits



Popular Circuits

USB Printer Chooser Switch
Low-Consumption Monostable Relay
Battery Indicator based on PIC18f452
MiniVol PGA2320 Volume Control
Electronic Coin Toss
August 2009
7 band audio graphic equalizer circuit
IR Remote Control Modulation Detector
diac controlled led flasher 3
USB audio DAC with PCM2704
I2C Interfacing Acceleration Sensing PCF8591
Automatic washing machine motor driver schematic