Studio Technologies Model 46 2-Wire to 4-Wire interface is making the comms connection for Observe Outside Broadcast, a premier remote broadcast and TV company that covers sports and entertainment events in Ireland. The Observe fleet of OB vans consists of the flagship HD1 high/standard definition truck, capable of fielding 25 cameras; the HD2 high/standard definition truck, offering eight camera capabilities and the SS3 standard definition truck, which supports 22 cameras. The trucks cover sports events that include RBS 6 Nations Rugby and international soccer games. Studio Technologies Model 46 units were chosen to interface efficiently between the existing 4-wire, 96-port RTS Telex matrix systems found in each truck and the remote 2-wire beltpacks carried by crew members. The Model 46 is designed to be the reliable connection between 2-wire full-duplex party-line intercom circuits and 4-wire audio circuits associated with matrix intercom systems. It provides two independent, full-featured, 2-channel interfaces. Each interface contains two hybrid circuits, which include an automatic nulling capability. The analog circuitry, under software control, provides excellent audio quality and high return-loss. The Model 46 is capable of supplying DC power, allowing direct operation of such devices as user beltpacks. It is also compatible with party-line circuits that include already include powering.