Dan, the answer depends on how you define electronics. I did buy some MTH locos in the 90's that did not have sound, other than horn, but used a non-mechanical reverse unit. About 17 years ago I upgraded them to PS2.
The electronic e-units were far superior to the mechanical E-units, and I recall back in the 80s converting a few old Lionel locos to them.
QSI made a variety of such units.