Need voice operated switch (VOX) circuits.

[pico]

Hello world,
I need some voice operated switch circuits.
Any body can help please.....

 

[flatulent]

op amp type

In general, you tap off a sample of the signal. Then you rectify it (try a half wave op amp rectifier circuit.) Then you go through an circuit to produce an average so that short sounds do not trigger it. This can be a series R and shunt C or it can be an op amp integrator with a resistor across the capacitor. Then you go to a comparator with a threshold that can be set (trip amplitude).

 

[VSWR]

A search on Google gave the following results:

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http://www.qsl.net/dl4mea/vox4b.htm

 

[JaBa]

Using A pic

I'm trying VOX for mobile phone and a BT-adaptor.Thanks to GaAs FET for showing the good link. I've got an idea. A PIC with comparator may be
used for the voice detecting and act as a switch.

 

[212853]

JaBa if you do come right, please let us know were this circuit can be viewed. I want to do basically the same, my PIC circuit work, but the voice circuit is a bit troublesome.

 

[elcielo]

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