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

Xor-gate-up-down-counter
Detector And Controller
Car and Motorcycle Battery Tester
12KV High Voltage Generator
basic power amplifier ic lm12 circuit
supercapacitor usb light
prop clock
Design Parallel Port Interface Project PCB
Model 300 Receiver
PIC16F630 14 Pin FLASH Based 8 Bit CMOS Microcontrollers
Using ADC 0808-ADC 0809 circuit chip consisting
Anti-jamming circuit



Top