Short-Haul Modem–C Async (SHM–C Async)

4 mi. (6.4 km) maximum

4-wire full-duplex

115,2000 bps at 4000 feet (1219.2 m); 57,600 bps at 1 mile (1.6 km); 9,600 bps at 4 miles (6.4 km)

115 VAC, 60 Hz ± wallmount, 9 VDC, 500 mA, 4.5 W maximum

1.5"H x 5.2"W x 5.2"D (3.8 x 13.2 x 13.2 cm)