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jonat
Apprentece
5 Posts |
 Posted - Aug 17 2006 : 6:21:03 PM
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I would like to record my phone messages on my computer. What do I need to do to match the output from the phone to the microphone input on my PC?
On your telephone recorder page, I see that the telephone wires go directly into the audio recorder's mic jack. Does the PC audio port work at the same voltages as an audio recorder, or do I need to design a circuit to adapt it?
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Aug 18 2006 : 09:38:05 AM
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Most computers generally have a line in, so you can connect that directly to the circuit on this site.
If you have a voice capable modem, you might not even need the circuit as there are many programs that can do this purely in software.
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jonat
Apprentece
5 Posts |
Posted - Aug 19 2006 : 08:30:08 AM
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What would the circuit look like if you removed the remote control part?
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Aug 21 2006 : 09:47:30 AM
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The circuit would consist of only R1, R2, R3 and C1.
It's also a good idea to put an isolation transformer between the PC and phone line to protect the PC.
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jonat
Apprentece
5 Posts |
Posted - Aug 23 2006 : 05:15:53 AM
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| Thanks!!! What transformer would you recommend? I'm studying electronic engineering, so my experience with actual hardware is very limited. |
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Aug 23 2006 : 3:07:02 PM
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| Any 1:1 matching transformer will do the job if it has an impedance over about 15K. |
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jonat
Apprentece
5 Posts |
Posted - Oct 01 2006 : 5:41:28 PM
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I bought a Critchley 9004 telecoms line isolating transformer.
The image is from the Critchley PDF for the xformer.
Which circuit elements is part of the phone line / phone, and which do I need to add?
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jonat
Apprentece
5 Posts |
Posted - Oct 07 2006 : 11:16:27 AM
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I figured the circuit out. When testing only the 3 resistor / 1 cap circuit, a pure sine input (5V) gets pretty deformed. When connecting it to a phone line (though a 2.2uF cap and the xformer), a lot of noise is introduced, and the signal is severly attenuated. Is the attenuation necessary to get the values low enough for the recorder input? And what is causing the noise?
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Telephone Recorder for PC
