Abstract: A test system for performing pair gain tests within a co-axial cable termination unit of a combined telephony/video system is described. The combined telephony/video system provides a set of telephony channels and video channels to the co-axial cable termination unit over a single combined telephony/video transmission line. The co-axial cable termination unit includes interface circuitry in the form of modems, CODEC's, and the like, for interfacing the set of telephony channels provided on the combined telephony/video transmission line with a set of respective telephone lines connected into a subscriber location The interface circuitry also routes the video channel of the combined telephony/video transmission line onto a video-only co-axial cable also connected into the subscriber location.

Abstract: An electronic business set terminal (24) includes a signaling gate array (40) that performs reception and transmission of 8 kHz signaling messages while avoiding collisions that may result in message loss. The signaling gate array (40) includes a receiver section (50) that detects for activity on an 8 kHz signaling line (20). A start bit detector (62) identifies the beginning of a receive message that is collected by a data collector (64). A transmitter section (52) sends a transmit message when no activity is present on the 8 kHz signaling line (20) and there is no indication from the start bit detector (62) that a receive message is in the process of being received. A collision detector and avoidance unit (72) checks for activity on the 8 kHz signaling line (20) while the transmitter section (52) awaits for a zero crossing to occur on an 8 kHz clock signal used in sending the transmit message.