... Reading,Environment monitoring 433Mhz RF Module, 5Km Wireless Data Transceiver 8 Frequency Channels, Data Transmitter Meter Reading,Environment ... ISM frequency band, half duplex integrated receiving and transmitting.Modules could directly connect with monolithic processors, PC, RS485 devices ... (>200millisecond), the module will be in sleep status, modules can not receive or transmit any data when sleep ...