Cam switches were developed in the late 1960s as a way of achieving further minimization. The switches leaf contacts are soldered directly to the PCB and custom cams engage the appropriate switches.
Also developed at the same time were the miniature pushbutton switches. Both the pushbutton and cam switches were used extensively for the first time in the 7000 series instruments.
This prototype board from 1967 was used to evaluate both pushbutton and cam switch performance.