It's a Model 866 Scott
Made in Hamilton, Canada. I remember that factory, it was not too far from my granma's house and we'd pass by on the city bus when I used to go stay with her.The Hamilton plant made most of Hoovers export products to the UK including the spinwashers. Probably had something to do with UK duties and excise being cheaper if they came in from Canada than the US at the time. I haven't got a Hoover blender though, yet!!
It's missing the filter cover inside as well..so using a towel for now. The guy I bought it from at the flea market says he gets Constellations in from time to time.
Google airider, there's a UK company marketing a new floating vac which looks interesting except for the price.
John..that's not a timer it's the on/off switch on the right, on the left is the pulse button which can be used for all 10 speeds. I have a 70's Avacado Waring somewhere round here with a timer though