I've been trawling the net for more QTQ-9 and NBN-3 RCA TK-11/31 pics and on YouTube found a film snippet of a QTQ-9 TK-31 in action with a zoomer lense, this was shown in a QTQ-9 40 years promo about 14 seconds into the clip:
http://www.youtube.com/watch?v=SgzHiKV6AtA
I've attached a still of it as well.