Abstract: The stability of the T/R module, which is the core component of active phased array radar, is crucially important. Due to the working characteristic of radar systems, where the transmit and receive signals share the same frequency band, TD serves as the fundamental operating mode for the T/R module to ensure loop stability. Transmit-receive switching time is a critical parameter of the T/R module. Merely conducting rough measurements to meet the specified requirements is insufficient. How to efficiently adjust timing sequences without compromising the operational stability of the T/R module remains a lack of effective guidelines. This paper explores a general measurement method for transmit-receive switching time, aiming to identify the minimum transmit-receive timing sequence and measure the minimal transmit-receive switching time. Based on this foundation, appropriate adjustments to timing sequence will not compromise the stability of the T/R module. At the same time, the self-excited problem which is observed during operation is discussed and the solutions are presented. This shows that the timing sequence has great influence on the transient loop isolation, and even the overall stability of the T/R module.