|I had dial up for maybe 10 years before they offered dsl. |
I had to disable incoming calls with a number sequence before each time I used dial up. Incoming calls would dial in past the the modem if I didn't use that code.
Incoming calls do not get a busy signal unless you use that code. My line knew the difference between a data fax and voice call.
See ATT's web site for that number sequence or try *70 or 1170 maybe. I don't remember what that number was but it took me a long time to find it before. May not be published anymore.
My neighbor had dial up longer and he may have it written down on his modem still. I know that because I told him how to prevent this issue and wrote it on the modem.
1/3 of highway deaths are caused by drunks. The rest are by people who can't drive any better than a drunk.