I still have, 3 old autos from "days of yore' " when Bluegill and Crappie fishing. What's been said, aobe, is true..............., "The auto feature is for line pick up only", more or less. But, I can also remember a time when I'd "over wind" mine, stripping off line and then hook a Bluegill or Crappie, about the size of my palm. "Whizzzzzzzzzzzzzz", went the levered spring, when I'd hit the release bar on the front of the reel and then some poor, little, Bluegill would have half his face forcibly strained through the tip guide of my fly rod!
You can still find near-new autos on Ebay for less than $25.00, freight included. However, what's scary, is there is an Italian reel manufacture, that is currently turning out an "all graphite aunto/manual reel" that has a nifty price tag of nearly $175.00!?! Someone, out there, probably knows the name, of the reel I'm talking about, but sorry it slips my feeble mind at the moment.
The only time I've seen an actual and logical use, for these old sewing machines, is when I've witnessed handicap fisherman using them, that do not have the physical ability to handle a conventional set up.
And, sorry to inform you, Jack M. but if you turn an old automatic, upside down and press the lever they won't shoot the line back out for you.................