Timer circuit


Posted on Dec 16, 2012

After one cycle of operation, SCR 1 will be on, and a low value of voltage is applied to the UJT emitter circuit, interrupting the tuning function. When pushbutton SI is pushed, or a positive going pulse is applied at point A, SCR 2 will turn on, and SCR 1 will be turned off by commutating capacitor CC. With SCR 1 off, the supply voltage will be applied to RE and the circuit will begin timing again.


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

After a period of time determined byihe setting of RE, the UJT will fire and turn SCR 1 on and commutate SCR 2 off. The time delay is determined by the charge time of the capacitor.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

CodeLock AVR
Arduino Mega 512 kB SRAM expansion shield
Mini FM Transmitter
Mini Operated Voice Relay Schematic
Load Cell Amp
Kawasaki KLR650 1995 Electrical
6 Channel Auto Reverse Sequential Disco Running Lightss
Mini USB-DMX interface
Convert Digital Mains Timer To Low Voltage
High Precision Digital Pulse Meter Circuit



Top