How do I connect the receiver from an old telephone handset to a 3.5 mm jack?
Thursday, October 29th, 2009 at
4:22 am
I want to be able to use it as a microphone for my laptop. I fiddled with the wires and for a while I was able to use it to record my voice on the computer, but very faintly and with a loud buzzing noise. I thought soldering the wires Viagra cheap in place would clear up the sound, but now I can’t get anything. How can I make this work? It’s a fairly old phone, I got it at the Salvation Army a few days ago.
a telephone receiver is the name for the "speaker" part of the handset. it uses a coil of wire and a PM. the coil is not shielded and is very susceptible to any magnetic field, which is the cause of the buzz. a dynamic mic has the same problem and they can’t be used near computers either.
a telephone transmitter is the name for the mic part of the handset, that is made of carbon granules that change bulk resistance when a voltage is applied. the telephone mic requires DC current to operate and the output will be quite strong, it should go to the computer line input and not the mic input. 6 volts should be adequate for the mic to work, and a cabon mic is not sensitive to magnetic fields. you will need to isolate the DC voltage from the output with a capacitor.