Electronic – Connecting landline to soundcard

computerstelephone

I'd like to connect my landline tellephone to my computer's soudcard, and I was about to do this when somebody warned me that the voltages are all wrong and that I will blow my soundcard.

To what voltages must I change the line, and how do I do that?

Also, the telephone line has two wires. How to I split them into input & output for my soundcards's ports?

Best Answer

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You can get a transformer from an damaged modem, like that:

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Reminder: In my country (Brazil) it is forbidden to record a phone conversation without the consent of another person on the phone.