Running LED Circuits

I think variation of blinking LED is art, Running LED circuits that i mean is a set of LED which blinking alternately. So that LED look like running with circular motion. As usual i rarely make PCB from blank PCB. But i often bought circuit PCB like this. Because it lower cost than make from blank PCB.

As usual, i got schematic paper like this

Main component of this circuit is IC timer 555 and CD 4017. I use Green LED, Blue LED and Red LED purpose to look like colorful. Total 20 of LED used. VR 20 K is potensiometer or trimpot that used to adjust speed of LED blink.

Top and bottom view of PCB

After Build

So, you can watch this video, please leave your comment, 

thank you for watching and visiting my Blog

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.