Pair Gain refers to which of the following?

Pair Gain refers to which of the following?

• A. A device that duplicates lines for load sharing.
• B. An inter-exchange routing plan.
• C. The number of conversations you get minus the number of wire pairs used by the system.
• D. A method to compress dial tones.

Answer: (C)

Pair gain measures how much extra calling capacity multiplexing provides over the number of physical wire pairs. In other words, it’s the total conversations you can support minus the number of wire pairs used. Each two-wire pair can carry more than one conversation when a pair-gain device multiplexes signals, so you gain additional lines without laying more copper. For example, if you have 4 wire pairs but can support 8 conversations, the pair gain is 8 minus 4, which equals 4. This concept helps quantify how efficiently the system uses its physical wiring. The other options don’t describe this capacity gain: duplicating lines for load sharing is about redundancy, an inter-exchange routing plan is about routing decisions between exchanges, and compressing dial tones isn’t related to the extra conversations provided by multiplexing.

Pair gain measures how much extra calling capacity multiplexing provides over the number of physical wire pairs. In other words, it’s the total conversations you can support minus the number of wire pairs used. Each two-wire pair can carry more than one conversation when a pair-gain device multiplexes signals, so you gain additional lines without laying more copper.

For example, if you have 4 wire pairs but can support 8 conversations, the pair gain is 8 minus 4, which equals 4. This concept helps quantify how efficiently the system uses its physical wiring.

The other options don’t describe this capacity gain: duplicating lines for load sharing is about redundancy, an inter-exchange routing plan is about routing decisions between exchanges, and compressing dial tones isn’t related to the extra conversations provided by multiplexing.