Post by thread:Looking for information

Hello all, I am working on a PIC based telephone project which will intercept and screen all incoming calls, without the phone ringing and conditionally, based the screening criteria, either issue a voice message or ring the phone and connect the phone to the incoming line. Can anyone point me to information on how to carry out the actual connect functions to the handset. This is the only part of the project I haven't figured out. Thanks in advance. 73, Dan Welch spam_OUTw6dfwTakeThisOuTqsl.net

At 06:15 AM 11/4/98 -0800, you wrote: >Hello all, >ÊÊ I am working on a PIC based telephone project which will >intercept and screen all incoming calls, without the phone ringing and >conditionally, based the screening criteria, >either issue a voice message or ring the phone and connect the phone to the >incoming line. > >Can anyone point me to information on how to carry out the >actual connect functions to the handset.Ê This is the only >part of the project I haven't figured out. > >Thanks in advance. > > >73, >Dan Welch >.....w6dfwKILLspam@spam@qsl.net > I've been looking into this as well. My theory is that most of the automated calling services these days have about one second of silence after you pick up the phone, but before you are connected to the salesperson. I think it should be possible to key off this delay to hang up on automated sales calls. The problem is getting the pic chip to answer the phone and to hang up at the appropriate time (or to actually ring you if it is not a sales call). In asking around about this, everybody I heard from said the best book on the subject was one that used to be sold by (believe it or not) Radio Shack. I remember that book and now regret not having bought one, but it is no longer in print. If you can find someone with a copy, I'd like to have one too! Best of luck with your project. John, W2FS

John Hansen wrote: {Quote hidden}> > At 06:15 AM 11/4/98 -0800, you wrote: > >Hello all, > > I am working on a PIC based telephone project which will > >intercept and screen all incoming calls, without the phone ringing and > >conditionally, based the screening criteria, > >either issue a voice message or ring the phone and connect the phone to the > >incoming line. > > > >Can anyone point me to information on how to carry out the > >actual connect functions to the handset. This is the only > >part of the project I haven't figured out. > > > >Thanks in advance. > > > > > >73, > >Dan Welch > >w6dfwKILLspamqsl.net > > > > I've been looking into this as well. My theory is that most of the automated > calling services these days have about one second of silence after you pick up > the phone, but before you are connected to the salesperson. I think it should > be possible to key off this delay to hang up on automated sales calls. The > problem is getting the pic chip to answer the phone and to hang up at the > appropriate time (or to actually ring you if it is not a sales call). In > asking around about this, everybody I heard from said the best book on the > subject was one that used to be sold by (believe it or not) Radio Shack. I > remember that book and now regret not having bought one, but it is no > longer in > print. If you can find someone with a copy, I'd like to have one too! > > Best of luck with your project. > > John, W2FS That book was great! It was written by some folks at Bell Labs, and covered things pretty well - My copy has disappeared (apparently forever), I'll HELP someone re-publish the darn thing (or buy multiple copies!) if it can be re-published - If I'm lucky, my copy may eventually re-surface, but don't hold your breath. Good book. Mark, .....mwillisKILLspam.....nwlink.com

At 12:23 AM 11/6/98 +0000, you wrote: >John Hansen <hansenspam_OUTAIT.FREDONIA.EDU> wrote: >> In asking around about this, everybody I heard from said the best book >> on the subject was one that used to be sold by (believe it or not) >> Radio Shack. > >Surely you aren't referring to _Understanding Telephone Electronics_? >I was underwhelmed. > Honestly, I don't know the name of the book. I've just had too many people recommend it to me. John Hansen

At 12:23 AM 11/6/98 +0000, you wrote: >John Hansen <@spam@hansenKILLspamAIT.FREDONIA.EDU> wrote: >> In asking around about this, everybody I heard from said the best book >> on the subject was one that used to be sold by (believe it or not) >> Radio Shack. > >Surely you aren't referring to _Understanding Telephone Electronics_? >I was underwhelmed. > Honestly, I don't know the name of the book. I've just had too many people recommend it to me. John Hansen