Bistable flip-flop practical circuit a

The bistable flip-flop circuit has the function of memory pulse signal. It has two stable states: the transistor VTi is turned off and
VTz is turned on; or VTi is turned on and VT2 is turned off. Triggered by sufficient external signals, the two states can transform into each other
(often called flipping). Bistable flip-flops can be used as memory elements , counting elements, contactless transfer switches and frequency dividing elements . The practical circuit of a
bistable flip-flop is shown in the figure