Cordless modem

• http://www.halfbakery.com/idea/Cordless_20Phone_20Jack
• You can add a phone jack to your cordless phone. I had a cheapo Vtech cordless
• I disconected the speaker and microphone.
• I connected the negative leads from the speaker and microphone together to the green lead from a phone plug.
• I then connected the positive lead of the speaker to a 10k resistor and the other end of the resistor to the red wire of the phone plug. I did the same with the mic.
• I then connected a third 10K resistor between he red and green wires of th phone jack.
• I can connect to the internet with this on my laptop, but only at 9600 or 12000bps, and slightly unreliabally.
• The battery does run down, but you can get 5 volts from the USB or keyboard ports and connect it to the contacts used for charging (the base set's charging voltage isn't regulated). But I don't think it could work with a regular phone. Regular phones take power from the lines. 48ish volts when off hook. 10ish when talking, and about 90 volts when ringing. There is full battery voltage applied to the microphone, but I don't think this is enough for a phone. You can talk between two phones connected together to a 9 volt battery.I don't recomend connecting a battery across the "cordless modem adapter", becaus you may fry it! You could get away with just resistors, or you may try a coupling capacitor (caps only pass the ac part of the signall, not the dc). I would try a moden transfrmer. connect one side to your mess of 0K resistors and cordless modem and the other side to your phone and a 9 olt battery. I didn't need a 9 volt battery for my modem, because the modem is not powered by the line, it's powered by the laptop. You could try to find some circuit module that fakes a phone line like form one of those pone extenders that plug into the AC lines and are sold next to satellite receivers.