Simple Telephone Timer Circuit PCB


Posted on Feb 4, 2014

Telephones are reaching its death point all over the world. however there is more than 350 million mobile phone users in india, but there are tremendous number of telephone users are there also. Well, this telephone timer is designed to help saving by controlling unnecessary time taken during pone calls. This simple timer circuit is better in its


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

accuracy because it is manually put on by the user when the call connects at the other end. The piezo buzzer provided in the circuit makes a beep along with an LED flash during every passing minute. The time will not so accurate, but there is not more than 2-3 seconds variation. you have to put ON the timer at the moment when call starts. Then it will do the job of alerting during each minute to suppress your conversation and save money.




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