Mini Police Alarm

Mini Police alarm actually is modified from siren circuits. Multivibrator circuits has been added as an input to siren circuits. Continuity from Siren Circuits that i've ever post. So this is schematic.

And this is photos of PCB that i've bought from top and bottom view.

Multivibraror is circuit which produce simultanously square wave purpose to generate vibration. This is usefull to vibrating siren sound. Fast vibration make siren sound like police alarm, and slow vibration make siren sound like Ambulance or Firefighter alarm.

So, this circuits able to modificated to many various alarm or sound. If you change value of C4 ( 0.05 uF) or 5 nano Farad with smaller value e.g 2.2 nano Farad, sound will be heard like bird sound.

I think this circuit is very cool to modified into many variation of sound alarm. As usual to try this circuit, i use 9 Volt Battery, Push Button Switch and Mini Speaker. As shown in this picture.

So you can watch this Video. Please leave your comment. 

Thank you for watching and visiting my blog.

Simple Siren Circuit

Continue from previous story,

Simple Led Flip Flop

I was buy some circuits PCB not only LED circuits but also Siren Circuits. Siren is like alarm which scream tone. In my country, siren often use in firefighter car otherwise launch time alarm for worker in the industrial factory . This is PCB that I was buy.

After open plastic package, I got this pieces of paper and PCB of course .

And It was i assemble like this

After that i use Push Button Switch according schematic paper. Push Button Switch use to start and stop siren buzzing. When position start ( Push Button Pushed ), The Siren sound is longer then higher tone. When position stop ( Push Button Release), The Siren sound is longer then lower tone until silent. This is it.

You can look this picture to overall wiring, I use 8 Ohm, 0.5 Watt mini speaker 2.5 Inch. On the schematic paper describe that circuits work at 6 Volt. But i prefer to use 9 Volt Battery.

And you can watch this Video. This circuits is simple to make and soldering.

Simple Water Level Alarm

In the bathrooms, sometimes i often open the tap water to fill the water tank and leave it to do other activities. But i often forgot to close tap water, After that, the water is spilled to much. Because water direct flow from electric pump, of course it also make a wasteful electricity. 

Not all water filling in the bathroom using automatic valves that will close when the water is full. One easy solution is install a water level alarm. The alarm will buzzing to people to tell that the tub is full. Water level alarm can be assembled with very easy. And then some of the main components that used are :

• 9v battery
• Piezo buzzer
• Transistor c 9014
• 470 ohm resistor

This is schematic of water level alarm that I was use, This is so simple and just need only 4 component electronics to make it work.

This is water level alarm that I was build. I soldering all component on PCB. I use two copper for water sensor. I got copper from piece of NYM cable. when both copper exposed to water, the alarm will sounding “ Tiiiiit……………”

this is a picture of the installation the circuit in the bathroom, both of copper can adjusted to level water which desired.

Why use batteries? This is the best way to avoid electrical line hazards. Of course safety is the main reason.  I use 9 Volt battery because a piezo buzzer that I used works on voltages from 6 to 9 volt. At a voltage 9 Volts, piezo buzzer may be ringing very loudly.

For more detail, please watch this video and don’t forget to leave your comment. Thank you for visiting my blog.

Beep Buzzer

One day, i visited my favourite shopping place in Surabaya my love city, Of course no other except 

"Genteng Market". I usually walk trough several alley and looking for unique something or some electronics part. That day i was looking for " Piezo Buzzer " to my favourite store. Sellers at the store ask to me,

Sellers  : What are you looking for ?

Me        : I was looking for " Piezo Buzzer" for around 9 Volt or 12 Volt.

Sellers  : There are two type, Buzzer with sound "Beeeeeep" or "Beep ... Beep .... Beep" ?

And then i was currious, I usually found Buzzer with sound "Beeeeeep" then i knew that evidently it has two type. Without much thought, i just said to sellers,

Me         : I will buy both of them, one for "Beeeeeep" and one for "Beep... Beep.... Beep".

Sellers   : Okay, the prize of one buzzer is Rp 7000. So total price is Rp 14000.

Me         : Okay, thanks.

This is photo of it with top view

And with bottom view

Both of photos is only Buzzer with sound " Beep ... Beep ... Beep " because i had forgotten to put another Buzzer.