Making Old Telephones Great Again (MOTGA)

[user113]

So I finally got the tone generator working, and come to find out it doesn't use the same frequencies as Ma Bell. It sounds like some fucking VoIP office system tones, which shouldn't have come as a surprise since that's what the chip was made for. It's disappointing just the same. This is the realness right here:

https://pbxbook.com/other/dtmftone.html

(Scroll down for the progress tones.)