Abstract: The terminal auto-check signal source of telemeter system is an important part to improve the reliability and maintenance of the whole system. The signal source can output the telemeter signal、data transmission signal, and time-frequency signal, certainly the signal has the ability to get data through the PCI data bus and has the ability to accept the monitor of the main-control computer. The way how to realize the QPSK signal is discussed and give the result of simulation and real test.