My first pack was an oiled canvas job, attached to a run of the mill aluminum frame. It was very simple, just a main pack compartment and a pocket on the top flap, with some D-rings around the edges so you could strap extra gear on. The hipbelt was 2" webbing, no padding.
I never did weigh it, but it couldn't have been more than 4 lbs total including the frame, so it was certainly lighter and simpler than most folks' first pack, at least as long as it was dry. It didn't carry half bad, either. FWIW, I've never seen the point of the mainstream bells 'n whistles internal frame packs, probably because the first one I used was so minimalist and ultimately functional.