Broadcast and alternate message time slot interchanger

It is common that communications such as telephone calls between calling and called lines be made by sharing a single communications path on a time division basis. Each call is assigned to a shared path for a short time interval, also called a time slot. It is known to interchange an input time slot to a different output time slot. Unfortunately, known time slot interchange arrangements insert an input sample in a single output time slot. The instant time slot interchanger extends an input sample onto a plurality of output time slots for broadcasting a sample through a plurality of locations. Also, the instant time slot interchanger may selectively insert an alternate message, e.g., an error message, in an output time slot.