@Fatman- What a great find, fun, colorful, and part of our hobby's great history! Hard to beat that. Oh yea, as far as "tipping you over the edge" - well, my friend, always glad to help . OK, going back to our series of posts on my TRENEX HO engine, I have finally figured it out. Yes, as per the box that Fatman kindly posted, this is a BATTERY locomotive. I took the engine apart and found the battery compartment, not really all that hard once you know where it is, UNDER the grey plastic roof. What I was calling a "switch" in the center of the roof is actually a "latch" which when slid forward, locks the roof in place. By chance I slid it backward and lo and behold, the roof came free revealing the battery compartment. It takes a lot of power...Two (2) R-6 1/6V cylindrical batteries and a single 6F-22 9 volt battery. I also opened the locomotive body to reveal the motor and a very complex (to me) circuit board. By following the wires, it does appear that it was possible to run this off of catenary by using pantographs. There is a metal contact that is wired to the motor under the plastic pantograph mounting. What I find is that this is a reasonably sophisticated locomotive much more complex than I imagined at first.
Here is the cab raised off of the frame to reveal the motor. Note the rather complex circuit board and the blue/yellow twisted pair go to the base of the pantograph. Another smart design feature is that the motor, quite heavy, sits directly over the driving axle providing extra weight for traction. Smart design.
Here is the roof removed showing the battery compartment. The two 1.6 Volt batteries sit in the middle and the 9 volt sits in the left end. The metallic "button" appears to be a contact that would allow the pantograph to provide power to the motor.
Well folks, that's it for me today. Best wishes to everyone.
Don