[kolleykibber]

Good times. I built a wardialler out of one of those science fair 150 in one kits and an Atari st using an rs232 data line to bounce a relay. found plenty, but the fun ended when the 400 quid bill came in. Endless paper rounds.

[jaystraw]

i've backspaced over trying to be nice but i don't think you a) could've made the dtmf tones, b) matched the impedance, c) modulated the serial signal even if you made a connection

please prove me wrong

[Gracana]

They’re describing pulse dialing, not tone dialing. Totally doable using a toggleable serial port pin and some basic electronics.