Voice scrambler 2011-01-13

ElectroMaster · Jan 12, 2011

ElectroMaster submitted a new article:

Voice Scrambler - With this circuit you can modify how your voice sounds by changing the pitch of your voice. This ci

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...

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cr0sh · Jul 21, 2010

Hmm - if you added digital pots for Tune 1 and 2, connected them to a microcontroller with a pseudo-random number generator, and synced the changes with the other end somehow (maybe via a signal mixed into the audio?)...it might be pretty damn secure.

doc b. · Jul 24, 2010

Sounds neat, theoretically.
Would the circuitry required be more complex than the scrambler circuit shown?
Would it be as easy/difficult to acquire a schematic of the circuitry used in "secure" U.S. military fone lines, or available telefone-signal, scrambler-descramblers?

khaled essa · Oct 15, 2010

thanks for all

dougy83 · Sep 20, 2012

Are there some junction dots missing perhaps? There's no feedback path.

Voice scrambler 2011-01-13

ElectroMaster

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cr0sh

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doc b.

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khaled essa

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dougy83

Well-Known Member

Voice scrambler 2011-01-13

ElectroMaster

Administrator

cr0sh

Member

doc b.

New Member

khaled essa

New Member

dougy83

Well-Known Member

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