It would be very hard...I`m thinking use a hands free kit (the cheap one thats just a wire with an ear bud and a microphone) and wiring the "speaker out" and "mic in" lines to the phone line, but I think there will be some voltage conversion problems. So you will probably end up using transistors to step down the voltage either way. But then you would have to emulate picking up the phone "off the hook" and again that could be tricky. As for dialling, if your phone is anything like mine it makes a tone when you press a button when making a call. Hold the speaker up to the microphone of a fully working standard phone and dial the number out manually, if it works then it could be feasible, you just have to figure exactly how a phone works and emulate it (I know I knowâ¦ easier said than done). All in all it`s probably not worth the trouble, I got a mini plug-in (phone line) phone small enough to fit in an altoids tin from the 99p shop. I suggest you just shop around for similar.