Ah! Thank you! This one really had me going "hm hm". Strangely enough it does not have an indication scale for its settings, nor does it have a facility to 'lock' the aluminium slide on the silvered coax tube.
Will see if I can figure out what range it has.
That said, I don't think I am ever going to use it, but prove me wrong HI
Many thanks to all that replied