GB/T 7621-1987
Active1200 bits per second duplex modem standardized for use in the general switched telephone network and on point-to-point 2-wire leased telephonecircuits
在电话自动交换网和点对点二线租用电话型电路上使用的标准化的1200比特/秒双工调制解调器
Application Summary AI generated
This standard specifies the technical requirements and test methods for a 1200 bits per second duplex modem designed for data transmission over the public switched telephone network and dedicated 2-wire leased lines. It is applied in telecommunications equipment manufacturing and network deployment to ensure interoperability between modems used for low-speed data communication, such as remote terminal access or early dial-up internet services. The standard defines modulation, interface, and performance parameters for reliable full-duplex operation in both switched and leased telephone circuit environments.
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