Analogue line, modem and call-waiting-tone

Formerly we were bound to an exchange of the German Telekom by one legacy analogue line and had call-waiting-tone let enabled. When you called us, while we were currently talking with somebody else, the exchange told us by call-waiting-tones, that another one wanted to get connected to us.

Configuration of T-Online

A call-waiting-tone would jam a modem connection. There is a built in "number for disabling hold" in the Dial-up connection. But this function does not hang up between disabling hold and dialling as expected by the exchange of German Telekom. Therefore I had substituted the T-Online software from my provider in my start menu by batch files like these for Windows 95, which temporarily also terminated the Trans-Send Fax software using the Close program:
@echo off
start /wait /min Close "Trans-Send Fax"
start /wait /min ComOut COM1 ATL1DT#43# 7
start /wait Online
start /wait /min ComOut COM1 ATL1DT*43# 7
start /min TsFax\Receive
or for the Dial-up connection of Windows:
@echo off
start /wait /min Close "Trans-Send Fax"
start /wait /min ComOut COM1 ATL1DT#43# 7
start \\Dial-up connection\T-Online
start /wait /min WaitDlg  "connected to T-Online"
start /wait /min WaitTerm "connected to T-Online"
start /wait /min Sleep 10
start /wait /min ComOut COM1 ATL1DT*43# 7
start /min TsFax\Receive

Explanation

The Modem connected to COM1 given the command ATL1DT#43# dialled the number #43#and thus controlled the exchange, so that it should no more send call-waiting-tones. 7 seconds later ComOut hung up the line and terminated. The batch waited until then, launched T-Online and waited until it terminated. In order to allow call-waiting-tones after terminating T-Online, I had to dial the number *43#. /wait will not give the expected result in a Dial-up connection. Instead I used the programs WaitDlg for suspending the batch first until successfully being connected and then WaitTerm for suspending the batch until the ending of the Dial-up T-Online connection. Sleep waited 10 seconds for the DLLs to free the modem. 

Last update on this page: August 30th 2004