To change a numeric parameter like the receive frequency, select this value from the 'SETTINGS' or 'SETUP' menu. The upper display line describes the parameter, the lower line shows it's value:
To set a new value, press 
. This clears all figures from the value display and shows '>' at the first column to signal the editing mode. Using the number keys, you enter the new value. The digits fill the entry field from right to left, like with a pocket calculator. The 
key may be used to delete the last digit.
To accept the edited value, press . This checks the entered value against it's limits and executes the parameter change. Pressing 
twice (the first key press clears the display) leaves the editing mode without changing anything.
If you entered an invalid value or a value out of range, a message indicating this appears in the lower line of the display. Press or in this case, the leads you back to the parameter you edited and shows the actual (unchanged) value of this parameter.