Press this submenu key to open the HPF Loss dialog box and the Units menu. Use the Up/Down arrow keys or the rotary knob to scroll to the desired dB value for the High Pass Filter, and then press Enter. You may also use the numeric keypad to enter a value and then press either the dB submenu key or the Enter key. The step increments and range for HPF Loss are listed in the dialog box. Refer to Spurious Emissions, Custom, or to Spurious Emissions Setup for Easy Measurement mode.