First you need to get a telnet Communication Toolbox tool to connect to the server.
The best is free, called TGE TCP Tool, and is available on my web site...
Place TGE TCP Tool in the extensions folder on your Macintosh, and run MacAPRS. You must now configure the program to use the new tool correctly.
Choose Settings/Communications/TNC via TCP. Enter the following information into the appropriate fields in the dialog box:
To connect to the server, select Settings/Open TCP via TCP
The stations will flood in. If you want to disable the sound temporarily, press the Caps Lock key.