This python script will detect modem events like DTMF Digits, Busy Tone, Silence etc from phone line using Raspberry Pi 3. Seems to do audio signal analysis to do this.
An open source device to connect a computer with an RS232 serial port to a telnet BBS. It does not use an analog phone line but internet through a wifi connection. Behaves like a Hayes dial-up modem, and it is designed and built for old computers. Plug it in, fire up a terminal emulator, and use the Hayes AT command set to tell it what to do. Can theoretically be used with any computer that has an RS-232 port.
Occasionally the designer sells them on eBay, but you can build your own.
A website that keeps track of BBSes that are still online in this day and age.
bbs computers networking modem dialup telnet bulletinboard
A software modem that pretends to be an analog dialup modem from the old days, only for communications it uses the IAX protocol to connect to an Asterisk VoIP switch rather than the PSTN.
vmdialer is a simple app that lets you operate a cellular modem (pre-paid or otherwise) from Virgin Mobile or Verizon on a Linux machine. The cell modem must be activated on a Windows machine before it'll function because the PROM has to be programmed with a special app, but once that's done you can use it with this app.
Note that the exact make and model is "Novatel Wireless MC760".
minimodem is a command-line utility which implements a virtual FSK (forward shift keying) modem. Hook it into an audio source and it will act just like a modem, sending and receiving data transmissions. Can also interpret recordings of transmissions and generate new ones from traffic you send it. Who needs a serial modem when you've got this?
FOSS terminal emulator software for linux that emulates Qmodem. telnet ssh bbs retrotech github Not only does telnet but it can be used with a modem, too! dialup text ansi telecom Does not have a native scripting language, but any utility which reads from stdin and writes to stdout can be used just like a script.
electronics retrocomputing How to build a 9600 bps modem for a c64 that is actually a wifi network interface. howto
howto rig up a computer at home to a cellphone with a cable and set it to automatically answer any incoming calls. Basically, the phone acts like a modem. It's supposed to be used for transferring data in emergencies (i.e., from a payphone). hacking Uses a piece of hamradio software called CallTTY, which implements tty and ttd (Telecommunications Devices for the Deaf) in software instead of hardware.