Voice Scrambler

Advertisements

With this circuit you can modify how your voice sounds by changing the pitch of your voice. This circuit can be connected to a phone and with a duplicate circuit on the end of the phone line, you can have a scrambled voice communication. The way the circuit works is as follows: If we cut the circuit in half at the T2 transformer and include the LM324 on the left side, you will see that the LM324 portion of the circuit is a tone oscillator which shifts the frequency of all input signals to a new higher frequency. When the voice and the tone oscillator mix frequencies the voice is not recognized. The voice signal is then inputted to the second stage which again shifts the voice signal again. I recommend that the first stage be tuned to a frequency that is 100hz lower then the second stage.

400Watt power inverter Variable power supply Wireless alarm systems
Power Supply   Switching Power Supply   DC to DC Converter   Inverter
Battery charger   Led flasher   Motor speed controller   LM317   IC 741
RF radiofrequency   Electronic control   Digital Circuit   Alarm home system
DC to DC converter step up voltage   Mini project   Temperature control
FM receiver   Dual power supply   Fluorescent lamp   Pic microcontroller
Led display   RF amplifier   FM transmitter   LM324   LM723   TL494
2N3055   LM338   SG3525   Li-ion battery charger   Pulse generator