HP 3330B Software Manual page 8

The left and right cursor keys can be used to move the cursor.
Backspace deletes the character to the left of the cursor.
Delete key deletes the character above the cursor.
Insert toggles the entry mode from insert to replace.
Home moves the cursor to the start of the title.
End move the cursor to the last character in the title
Enter closes the Enter Title screen and display the title on the screen.
F2
Pressing F2 allows the user to store the current sweep in one of the reference
memories. The following screen appears:
The up / down arrow keys are used to select the memory. Pressing enter transfer
the sweep to the memory and closes the Save Reference screen.