|H O M E >> C I R C U I T L A B|
ASHOK K. DOCTOR
A flashing beacon has many uses. It can be employed as a distress signal on highways or as a direction pointer for parking lots, hospitals, hotels, etc. Here we present a flashing beacon that uses well-known regulator IC LM317T. As LM317T regulator can deliver more than 1 amp. A small 12V, 10W bulb with a high-quality reflector can serve as a good visible blinker.
A 12-15V, 1A DC supply is connected to the input pin of the IC. A 12V, 10W bulb and a combination of resistors and capacitors are connected between the output pin and ADJ pin of the IC as shown in the figure. The IC is provided with an aluminium heat-sink to dissipate the heat generated while delivering full current. Since the IC has an inbuilt switch-on current limiter, it extends the bulb life.
For the shown values of resistors and capacitors, the bulb flashes at approximately 4 cycles per second. The number of flashes depends on the charge-discharge time of the capacitors. Different values of resistors and capacitors can be used to increase or decrease the number of flashes.
Electronics for You
LINUX for You
Facts for You
Electronics Annual Guide
Linux & Open Source
Science & Technology
|© Copyright 2012 EFY Enterprises Pvt. Ltd. All rights reserved.
Reproduction in whole or in part in any form or medium without written permission is prohibited. Usage of the content from the web site is subjectT etor ms and Conditions