Introduced: circa 1962
OK, here it is, the absolute worst locomotive I've ever owned. Although to be fair, these old Lone Star "Treble-O-Lectric" locomotives were some of the first N-scale offerings ever and were initially marketed as nothing more than toys. Beginning in the mid to late 1950s, Lone Star (a British company) began building a line of N gauge push toys, and by the early 1960s they had begun motorizing them. Arnold picked up on their popularity and began work on their own line of similarly sized models and N scale was born (or more accurately, OOO scale - it would be some years before it came to be known as N scale).
Believe it or not, this thing actually employs a rubber band drive! And how about those bizarre claw couplers? Yikes! Truly horrible and obviously only useful as a collector piece. Still, an important piece of N-scale history. The entire Lone Star line (along with Arnold) get a big writeup in the 2/64 issue of Model Railroader, the first piece in that magazine discussing the new "OOO" scale trains. The first MR advertisement for Lone Star trains appears in the 11/64 issue and lists UP, New Haven and C&O versions of the F7.
Usually when you get one of these, if the motor works at all it still won't move because the ancient rubber bands are shot. If you have one with a working motor and want to actually get it to run, try swapping in some orthodontic rubber bands. They're small, tough and very elastic. Removing the shell is very simple, requiring the removal of two small screws (twist each truck to reveal them).
I'm not sure when these models were ultimately discontinued, but I think it's probably safe to say that they didn't last much past 1970.
Here's the New Haven version -
Here's one of the early "push toys" -
Here's an advertisement from the September, 1963 issue of Railroad Model Craftsman -
Here's a complete trainset -