Ever since I switched to broadband internet a few years ago, I have not used modems, nor dialup internet. Over the years, I have collected some modem tips and hints that assist in maintaining the best connectivity possible, and optimal operation.
Note: To the change the settings below in Windows, do the following: Start / Settings / Control Panel / Modem / Properties / Connection / Advanced In Extra Settings, add the string indicated below in each section.
Maintain Modem connection even if line quality is bad
Normally, if the line quality is bad, the the modem will disconnect the line. This can be a problem with areas that suffer from poor telephone exchanges, cabling problems, ...etc. To get the modem to maintain the connection despite the above conditions, change the modem settings to add the following setting:
Fast dialing in tone
If you can use tone dialling, the amount of time it takes to dial can be changed using the S11 register. It gives the duration (in 100hundreds of a second) to send each tone while dialling. The default is usually 95 (almost a second.) How fast you can dial depends on the phone company's switching equipment which handles your line. The minimum duration is 50, almost twice as fast, and that speed often works. If it doesn't work, use a higher number.
Modem to report correct speed
Many modems only report the speed of the serial line and not the speed over the telephone line as default. This can be confusing if you set the speed to a high one (e.g. 115200), and will not let you track the real speed that the telephone line is allowing you.You must configure these modems to report the true line speed (add to modem init or dial string). For many modems this command is "W2". If you want to add it to the dial-string (typical "ATD"), the new dial string would be "ATW2D".