To display the full tree choose the 'Reset Logical Zoom'
item from the 'ETC' menu of the 'ARB_NT' window.
NOTES
To display subtrees (logical zoom) activate the 'LOGICAL
ZOOM MODE' by clicking on the <Zoom> button of the 'ARB_NT'
window or pressing the 'F5' key on the keyboard. In the latter
case, the cursor has to be placed within the tree display area.