Digitally Adjustable Dancing Lights ,Auto Fan Speed Controller ,555 Timer PWM Audio Amplifier & Freeze Alarm



Digitally Adjustable Dancing Lights
You may have gone over a few sorts of flexible moving lights (gleaming LEDs). A large portion of them utilize presets (variable resistors) to alter the rate of exchanging. Being a mechanical segment, the preset effortlessly destroys with utilize furthermore presents clamor in the circuit. The circuit introduced here chooses distinctive estimations of resistors to control the recurrence of an astable multivibrator utilizing clock IC 555. 


  

Auto Fan Speed Controller
Utilizing this circuit you can control the speed of 12V DC fans utilized as a part of autos. The circuit is worked around clock 555, which is wired as an astable multivibrator. The yield of the multivibrator is bolstered to IRF 540 MOSFET. The fan is associated between the positive terminal of the battery and deplete (D) of MOSFET T1. Capacitor C1 is associated in parallel to the fan to balance out its speed. Free-wheeling diode D1 shields the engine from back emf. A breaker is incorporated for security. 

  



Freeze Alarm
On the off chance that you feel undermined or require crisis help, essentially actuate this caution. It will get the consideration of others for prompt offer assistance. The caution will sound for three minutes and after that stop. Particularly valuable for ladies voyaging alone, it is sufficiently little to stash or convey in a purse.
Here is an extremely basic and in addition exceptionally helpful venture against pack grabbing caution, utilized as a part of sack on the other hand bag keeping in mind the end goal to keep from grabbing. The sound delivered by against sack grabbing alert resemble police horn to get consideration of individuals when somebody endeavor to grab your pack or bag. Circuit Description of hostile to sack grabbing alert The heart of this whole circuit hostile to sack grabbing alert is operational intensifier IC CA3140 (IC1), arranged as a comparator. The two data sources (rearranging and non – rearranging) is given to stick no 3 and 2 of operational speaker individually and yield is gotten from stick no 6. Here IC2 (clock IC NE555) is utilized as monostable multivibrator. The planning part of against pack grabbing caution is R5, VR1, and capacitor C2 with the given esteem in this circuit chart lets the season of clock is around 1 minute. For sound area, IC3 is utilized as alert tone generator with an inbuilt oscillator. At long last the yield is acquired from stick no 3 of IC3 and intensified by transistor T1 with a specific end goal to get want level and in conclusion nourished to amplifier for yield.