Search This Blog

Thursday, April 23, 2015

Door Guard Knob Alarm circuit.

Door Guard Knob Alarm circuit.
This is Door Guard Knob Alarm circuit with touch system. When thief caught on the door handle, makes it sound an alarm once. Use the the detector capacitance within the body.This project is a small and economical. Ideal for travelers or those who want security.
How does it works
The circuit working as Figure 1 a 9V battery there are the regulator to reduce voltage down to 5V . Which consist of a transistor-Q1,R1 and ZD1 serves as provide to some circuit. In circuit include the frequency generator of three set. Firstly set have L1,C2,C3 and Q2, the signal is coupling with C4, then them are bypass a negative range go out with D1 so have only a positive signal range to bias Q3.

No comments:

Post a Comment

Best Product On Amazon Must Buy

Best Electronics Soldering Iron Kit - https://amzn.to/3gIulii

Best Desoldering Pump Soldering Iron - https://amzn.to/3egN4Qp

Best Screw Driver Set For Repairing - https://amzn.to/2OsA0ND

Best Cord less Screw Driver Set - https://amzn.to/3eqvtWw

Best & Cheap Digital Multimeter - https://amzn.to/467dOOb

Best Fold Scope Microscope Basic Kit - https://amzn.to/393WI6o

Best & Smallest 60x Microscope - https://amzn.to/477r5HQ

Microware-20x-to-1000x-8 Led-usb -   https://amzn.to/2W8DGs0

Best Magnifying-Soldering-Stand - https://amzn.to/2ZVcZrM

Supper LED TV Backlight tester - https://amzn.to/3gLyXEo

Mini Hand Drill and 20pcs Drill Bits - https://amzn.to/3fiEWAc

Popular Posts