Most stock TS-940S' require 30 to 50 mS to switch back from TX to
RX. This can be reduced to less than 20 mS by cutting the center
lead of Transistor Q68 on the Control Unit PCB.
After the modification, a slight "click" will be heard in the speaker
during switching. However, this is no big deal to the AMTOR nut
because of the improved switching time.