Apparatus and method for CNG detection with call waiting

A method for detecting call waiting and facsimile CNG signals on a busy telephone line while connected to a functioning computer modem so that if the signals are received the line will be switched to a second call and a connected facsimile machine whereby a data transmission can be received, the method comprising the steps of:

• (a) monitoring a busy telephone line for a call waiting signal;
• (b) upon detecting a call waiting signal on said line, generating a first “hook flash” on the telephone line to cause the line to be switched to a second call;
• (c) monitoring the second call on the telephone line for a facsimile CNG signal;
• and
• (d) upon detecting a CNG signal on said telephone line, applying a bias voltage on the computer modem to maintain it in an active state, generating a plurality of ring signals to activate a facsimile machine to receive said data transmission, connecting the facsimile machine to the telephone line when the facsimile machine answers in response to said ring signal, and generating a second “hook flash” upon the completion of the data transmission to switch the telephone line to the first call and attempt to reconnect the active computer modem.

A telephony device for detecting CNG function signals on a busy telephone line after a call waiting sequence and switching the line to a connected facsimile machine, the device comprising:

• (a) a routing device having at least one telephone line input and one or more outlet ports connected to telephony devices including a facsimile machine;
• and
• (b) said routing device includes:
• (1) a call waiting detector for receiving an incoming call waiting signal on the telephone line while busy with a first call, and switching means for generating a “hook flash” so as to activate a call waiting sequence and switch the telephone line to a second call when a call waiting signal is detected;
• and
• (2) a facsimile CNG signal detector for monitoring said telephone line when the second call is connected and triggering said switching means to connect the facsimile machine to the telephone line when a CNG signal is received.