Timer


Posted on Aug 4, 2012

The timer can be used wherever time periods of up to seven minutes duration are needed. To turn on just touch the turn-on plate, and after the selected time has elapsed, an alarm will sound for a short period, then automatically turn off. The turn-on touch plate, labeled TP in the diagram, is made up of two metal strips about 1/16-inch apart. Bridging the gap with your finger activates the timer. For more time range, increase Rl and/or Cl. R2 and C2 determine the period of time that the alarm will sound


Timer
Click here to download the full size of the above Circuit.

Increasing either will extend the time. The tone of the alarm is determined by R3 and C3. Increasing either lowers the tone, decreasing them raises the tone.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Proteus
Waveform Capture and Control
SEM/STEM detectors and CRTs
usb controlled rgb led
Troubleshooting a Triac Motor Control Circuit
microcontroller Analog to Digital Converter and Negative Voltages
FM Transmitter Circuit Type Versatile
60W Linear amplifier
Car Battery Failure Detector
Arduino Running A DC Motor and High Current Lamp
Selfrunning Free Energy 5 KW Kapanadze 4
Ensemble II VHF RX rf



Top