Wilkerson Instrument Company”s DR9031 wireless transceiver provides analog inputs and outputs and discrete inputs and outputs for point-to-point data acquisition and control. The DR9031 wireless transceiver provides bidirectional analog and contact closure data transmission to a companion DR9031 where the data is recovered. The analog data is recovered as two 4-20mA outputs, and the switch data is provided by optically isolated NPN transistors outputs. The analog inputs available are dual-channel DC voltage or currents, single-channel RTD, or strain gauge bridge inputs. The bridge version provides 10VDC precision excitation for up to four 330 ohm bridges. For the single-channel inputs, the two 4-20mA outputs are both proportional to the single input. The DR9031 has a choice of three radio frequencies — two in the 915MHz ISM band and one in the 2.4GHz band. All use spread spectrum frequency hopping technology. Each RF module has a choice of seven Hop sequences. This allows up to 21 systems to operate in the same locale without interfering with each other. With proper antennas and installation, the 915MHz units can function reliably over a 20-mile range.