You most certainly are. The unit does
not use batteries! Fret not, 'tis a common error. Further, should you have one, you could possibly make some money as it is a rare and, probably, valuable artifact. The origin is interesting; Many, many years ago there were attempts to combine classical physics with the up and coming particle theories. You no doubt recall the venerable Isaac Newton (Newt to his friends) and the 'black body' theories of the late twentieth century? Many scentists of the day attempted to solve the riddle of the apparently infinitely available energy postulated by the 'black body' system with that of dear old Isaac (you know, 'you can't get owt from nowt') It would appear that you may have come across one of the early versions of the experimental apparatus which was used during this era - it consisted of an oven, or stove, painted in matt black and looked something like a London cab mounted upon a system of short stubby legs. Be wary, though - some cheap imitations were produced in the far east (Margate, I think) which
did rely on batteries, the housing for which was cunningly disguised as a control knob.
My local charity shop recently had a Parroting warbler advertised but I missed it - was I unlucky?