Position: Index > Simple Circuit >

Simple audio alarm with transistor

2015-01-11 15:10  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.

The work of the circuit when press switch S1 will have the electric current flows through R1 go to pick the electric charge at C1 at a pin B of Q1 as a result, will have electricity pressure then until make Q1 work.

Simple audio alarm with transistor

When Q1 work Q2, as a result work with, be make have current flow through pin E come out the way pin C of , Q2 change R4 go to a loudspeaker. By C2 will charge when C2 charge with full speed ahead pin B of Q1 have low voltage poverty Q1 do not work. The Q2 stop work with make C2 disgorge load change R4, SP1 and R3 down ground poverty voltage at a pin B tall go up, as a result make Q1 begin the work again and make Q2 work, then born the sound at SP1. Which Q1 and Q2 work until quickly cause frequency at a loudspeaker. When we liberate switch S1 as a result cause C1 begin discharge. It make voltage at pin B of Q1 be down. It make the frequency has that quietly, then until switch off go to.


Reprinted Url Of This Article:
http://www.eleccircuit.com/simple-audio-alarm-with-transistor/