[GreenKeys] Teletype Highspeed (>100 wpm) Equipment Question

[Nick England]

I spent 5-6 years in grad school programming/maintaining a Varian 620 minicomputer with high speed tape. I think Tally punch and Oki reader maybe. Photo of our system in use by another grad student at
http://www.virhistory.com/ncsu/varian620-01.JPG

It got a lot if use and I can't recall ever doing much more than cleaning. Maybe a quick alignment so the hole sensors would sample coincident with the center of the sprocket hole. 

It was quite reliable but after I created hardware interface/controller & software to some 9-track mag tape machines, it didn't get used too much. 

Nick