An example of one of these is the clock field in the State Format
Specification menu. When you select the clock field in this menu it will
pop-up and show you all five clocks (J, K, L, M,andN). When you select
one of the five clocks, another pop-up appears showing you the available
choices of clock specifications.
Figure 3 - 1. State Clock Pop-up Menu
Figure 3 - 2. State Clock Pop-up with K Pop-up
HP 16510B Using the Front-Panel Interface
Front-Panel Reference 3-5