Electronic B-C-D counter in 8421 code - resets previous counting decade via transistors having bases coupled to outputs of first flip=flop

摘要

The counting circuit has a tripping impulse lead. In the intermediate regions of the flip-flops transistors or similar components are installed. The transistors of the impulse lead are controlled from the count outputs of the flip-flops. Flip-flops of type A are not directly tripped from the impulse lead but rather indirectly through control of other transistors. Flip-flops of type B are directly tripped by the impulse lead. The flip-flops are tripped from the L-H flanks of positive impulses or by corresponding formulation from the H-L flanks of negative impulses. The resetting of a counting decade after the tenth counting impulse is effected through the first flip-flop of the next counting decade.