How does this circuit work ? Answered

I acutely got it from this link

http://www.youtube.com/watch?v=zWPwtay0dxM

check it please :)

Thank you

Pair of astable multivibrators. One runs at a lower fixed frequency, the other doesn't.

what is the Purpose and interest of these part (why do we have to use it in this circuit )?

- 555
- multivibrator
- polar capacitor
- non polar capacitor
my project will be tomorrow I need your help please

Read what I have written in my report . tell me if I'm wrong

Description:
• 555 used two times because we want to produce two different voice in the same time .
• Pair of astable multivibrators. One runs at a lower fixed frequency, the other doesn't.
• Variable resistor used to produce different frequency for each 555 and to control the voice .
• Resistor used to protect the capacitor from damage .
• Ceramic Capacitor (non polar capacitor) used in a circuit that has high frequency like police siren .
• Electric capacitor ( polar capacitor) used because it has a high capacitance to store the voltage and it has a small resistor .


Thank you so much :)

The variable resistors do different jobs in each circuit - find a site that shows all the possible conenctions for a 555 - particularly, and here's a clue "VFO"

The polar caps here are largely used because its a cheap way to get lots of capacitance. Likewise, non-polar caps are avaliable in smaller sizes.

Steve