PCTTY is a Windows computer program that sends and receives baudot TTY phone calls through a data/fax/voice modem and also, with the aid of a SIP Tapi TSP, through IP Telephony.

The Source of the latest version of PCTTY has been released to the public as public domain. People interested in building PCTTY from source or working on it can go here. This includes the web interface of the recently released PCTTY bank where a number of PCTTY instances on a Windows machines are scheduled by a Perl script on a LINUX box.

PCTTY's web interface has been revamped and we are now offering a free service where anybody on the web can call any TTY on a landline in Australia and have a baudot TTY conversation with that TTY. Simply go to:

to try the service out. (Initially only one phone line will be operational but more will come online later). Feedback is appreciated.

PCTTY v1.84 also has DTMF tone capability for interaction with Interactive Voice Response (IVR) systems. Simply hold down the CONTROL key and strike a number key (or # and *) at the same time, and a DTMF tone will be issued from the PCTTY program.

PCTTY v1.84 now has big text support. Outgoing text is lowercase red and Incomming text is uppercase black. Text is now sizeable so that short of sight people can use PCTTY as well.

PCTTY v1.84 now capable of SIP 2.0 IP Telephony when the ComISDN TAPI TSP is installed and configured. Go here to find out more.

On Windows 98 and Windows ME a wave modem driver must be installed along with the regular modem driver. This wave modem driver is normally installed on modem installation time. On Windows 2K and XP an audio device needs to be installed with the modem at installation time. This audio device normally installs correctly for plug and play modems. See the FAQ for more help on this.

PCTTY v1.84 will run on Vista with the following provisos:

  1. Most voice modems don't have drivers for Vista. The only voice modem I have seen work on PCTTY and Vista is the Hiro 50113 USB External Data/Fax modem. I bought this from Amazon.
  2. Unless you have Vista SP 2 you need to apply this hotfix which is described here quite well. I have Vista SP 1 (x64) and I had to apply the (x64) version of this hotfix before I could run PCTTY successfully on Vista. (Please remember to apply the hotfix for your flavor of Vista (x86(32 bits) or x64(64 bits))
  3. Note: One person has reported that the above Microsoft Hotfix does not solve his problem. He has Vista Ultimate 32 SP2 bit OS. Please report your experiences with this hotfix via the "Report Bugs" link at the top of the webpage.

The PCTTY program is freeware.

PCTTY is perfect for the friend or family member of a deaf person who has a TTY machine. With this program they can communicate with their deaf friend or relative and save the cost of a TTY. With the "Echo On" feature the other side of the phone call can be relayed to the computer's speakers. This makes it easy for hearing people to understand what is happening on the other end of the phone, whether it is ringing or busy or if a person or tty answers the call.

The TTY was created in the early 60s by deaf physicist Robert Weitbrecht. A chapter in the book "Silence of the Spheres: The Deaf Experience in the History of Science" published by Bergin & Garvey deals with his great achievement.

Enjoy PCTTY and drop me a line about how it works.