Simple telephone test circuit

Posted on Feb 20, 2013

I have used this type of circuits for quick testing of telephone equipment. This is a quick hack that does not exactly resemble the characteristics of the real telephone network, but is enough for this kind if applications. If you want better simulation, change the resistor to 600 ohm and increase the power supply voltage. And by the way you can also feed signals to telephone if you connect the circuit output wires to small amplifier output.

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