Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

[SOLVED] Sound Detecting circuit

Status
Not open for further replies.

motoshan

Junior Member level 2
Joined
Jan 1, 2014
Messages
22
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
152
Hello all..
I would like to ask a question regarding a circuit that must produce some output upon detecting some sound signal.ill describe in detail...

  • consider there exist a system
  • the system must accept an input sound from mobile phone(just imagine as a "LONG BEEP" and "SHORT BEEP")
  • Now i want to switch-on RELAY1 for the "LONG BEEP" and Switch-on RELAY2 for "SHORT BEEP"
  • And Switch-off the Relays , if once again it receive the corresponding BEEPS
  • how can i implement this system


Please guide me in right path.Iam a computer science student and i hav a software + hardware project to implement.I knew that there is some clap-switch circuits, But these clap switches just switches according to the input pulses No comparison is there..
 

phobos1

Full Member level 2
Joined
Jan 18, 2010
Messages
135
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
Salem, Tamil Nadu, India
Activity points
2,112
u could try dtmf

hxxp://www.circuitsgallery.com/2012/07/dtmf-dual-tone-multi-frequency-decoder-circuit-schematic-using-m8870-ic.html
 

motoshan

Junior Member level 2
Joined
Jan 1, 2014
Messages
22
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
152
u could try dtmf

hxxp://www.circuitsgallery.com/2012/07/dtmf-dual-tone-multi-frequency-decoder-circuit-schematic-using-m8870-ic.html

Thanks for the Kick Start!!!!:razz:
 

motoshan

Junior Member level 2
Joined
Jan 1, 2014
Messages
22
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
152
After following DTMF technique. I had built a circuit successfully!! It uses a decode IC and a D flipflop. But my question is why should we use a D Ff here since we hav a high out put on corresponding BCD pins on the decoder IC.Can i connect the relay directly to any of these output pin?

When i press key 1 the decoder decodes it and the Q1 will bethe only pin in high state.so my question is is it safe to connect relay diretly to this pin?
 

heena17

Newbie level 3
Joined
Jan 26, 2014
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
24
When i press key 1 the decoder decodes it and the Q1 will bethe only pin in high state.so my question is is it safe to connect relay diretly to this pin?

Connect pin directly to relay ? You wanna burn your ICs and other components.
You need to output it to proper resistor to the base of switching transistor which can take relay load
Relay coil will have protection diode in parallel. Check for polarity as it will be connected reversed.

You can use relay driver ICs also but I have not yet tried any
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top