"Adding a rotary tuning encoder:

The encoder is wired to the three pads to the right of the display viewed from the top of the board and to the left of U9 from the bottom, where the pads are labeled. Any mechanical or optical encoder with Quadrature outputs can be used. There are many to choose from. A suitable panel mount encoder would be Mouser part # 652-PEC11R-4220F-S12. This encoder also has a push switch built in which the builder might elect to wire to the Fn switch. "

73,

Marty KD2JQG