Please comment on my project >< thanks~

[zgnoh]

There is an input current from a CD or a microphone.
Then if the amplitude of the sound exceeds a certain level, it activates the switch opening circuit to open a switch.
The circuit diagram is here, pls click.

Is there any mistakes/flaws with the circuit?
moreover, is the "Voltage Follower" correctly used? I suppose a voltage follower = two "not gates" in conjunction. is it like that?

Thanks very much. I know this is just so simple as high-school level.

 

[zgnoh]

oh, sorry, if you don't see the diagram, open a new browser and paste the link there &gt;&lt;

 

[ante1]

Hi,

This is what I get:

Forbidden
You don't have permission to access /zipzipivan/Project.GIF on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.


--------------------------------------------------------------------------------

Apache/1.3.33 Server at www.hostima.net Port 80

 

[zgnoh]

I'm very sorry,,, can you open a new browser and paste the link to see it... I don't know why it is like this too&gt;&lt;

 

[zgnoh]

The link is okay now :'(,,, pls help me. thanks :-*

 

[ante1]

Hi,

I can

 

[MP1]

I am only guessing here, but it looks like you want to activate a relay with the amplitude of the sound.
Is this correct?

MP

 

[zgnoh]

Hi,

I can

 

[zgnoh]

I am only guessing here, but it looks like you want to activate a relay with the amplitude of the sound.
Is this correct?

MP

thanks, yes you're right. IF the amplitude of sound exceeds a certain level, it activates an electromagnetic relay.
I have several questions:
1) Is Voltage Follower = two "not gates" used in conjuction?
2) Do I have to amplify the amplitude of sound so that the voltage is large enough?
3) Is there any bugs/logic error in the circuit?
4) Any improvement or more convenient ways?

Thanks~

btw, if I want to make use of the frequency of sound instead of amplitude, how can I make it? thanks~!!!

 

[zgnoh]

this is what I mean filter circuit

Voltage Follower

 

[MP1]

The amplitude of sound is simply voltage. You can use a comparator to determine the threshold at which the base of a transistor has excitation and trigger a relay from that. This is, in my opinion, the simplest method.

MP