Read the information posted by "Clivetobin" and found most of it right on target.

As a retired owner of a Audio/Visual repair business, I worked on them all as a service facility for one of the largest school districts in the State.  Not only did I repair 16 MM projectors for the school systems, but the Big 3 as well.

The 100 thru 500 Bell & Howell series were pretty much athing of the past beyond the early 70's.  Where I disagree with Clivetobin would be the bum rap given the 1500 and 2500 Series.  With routine maintaince, they gave much less problems than the older models...and were much more efficient.  I rarely ran into wormgear problems.  I used lubricants recommended and provided by B&H.  I couldn't say that for the older models...but of course time and use will always take it's toll.  Having said that, there will always be a warm spot in my heart for the really old timers like the B&H 179.  Heavy, manual thread, seperate speaker, short lamp life...it was still a class act.  However compared to the 2500 Series, it was like a Ford Model T compared to a new Cadillac...but that's progress.  Sadly today...16 MM's are becoming a faded memory...like 78 RPM records.

In any event...it was fun while it lasted, and I was glad to be part of it.