DeadHead@cup.portal.com (Bruce M Ong) (04/14/89)
I am looking for a chip that can take the telephone line input signal and filter it, demodulate it, and then output the analog signal as a pure voice signal in the receive mode, and in transmit mode, take an analog unmodulated voice signal, modulate it, and send it out to the telephone wire. INTEL's 82027 comes close but it's not exactly what I am looking for. Behind this telephone handling front end I plan to build a voice analysis/ synthesis system (answering machine). If you know where one can find something like that, I'd appreciate hearing from you. Thanks Bruce uucp: sun!portal!cup.portal.com!deadhead domain: deadhead@cup.portal.com
ddurbin@polyslo.CalPoly.EDU (Daniel A. Durbin) (04/15/89)
The Xecom XE1201/1203 MOSART should more than fit your requirements. The listed features of this device are: - small size: 2.25"x 1.0" x 0.5" -Full Bell 212A & 103 compatible - 8251A software compatible -DTMF or pulse dialing - Call Progress monitoring -DTMF reception and decoding - Software controlled audio interface for voice communication or acoustic coupling - FCC registered -Parity generation & checking - Synch byte generation/detection -Extensive inbuilt diagnostics - +/- 5VDC power only -Telephone-line diagnostics - Voice synthesis option (1203) -Synch/asynch operation. - Connects directly to phone line Xecom also has a development kit which includes a board to fit the IBM-PC slot. The device was featured as a Circuit Cellar Project in BYTE a couple of years ago. I have built an answering machine plug in card for the IBM PC and will be marketing them this summer. I didn't use the above chip however. I used a combination of a number of chips. For the speech circuit (the one that does the transmit and receive voice modulation), I used the National Semiconductor TP-5700 Telephone Speech Circuit which is available from Aero Electronics as well as numerous other distributors. I am putting an information package together on my Voice Mail Card and will be sending it out at the end of the month and I'll include a copy to you. By the way, my card was originally a senior project at Cal Poly. Daniel Durbin___________________________________________________ SysOp: Cygnus X-1 BBS | CIS: 73447,1744 (805) 541-8505 (data) | GEnie: D.DURBIN EL major at PolySlo | ddurbin@polyslo.CalPoly.EDU