Rotary on-off dimmer switch to control AC variable output on HO Transformer

probably not.  since they are electronically controlled.  your best bet would be a wire wound rheostat NOT to be confused with a potentiometer.  or a wire wound adjustable resistor.  I have all this available in my online store, but since im not a forum sponsor, I don't think im allowed to post the links or names here .

Ireland posted:

I would be interested to know if the subject switch AKA the typical household wall mounted rotary dimmer switch will work to control the AC fixed output from the HO power Pak and hence power the trolley by turning the knob...

NO.

But, if you have several, you can plug the power pack(s) into the dimmer on the 120v output side of the dimmer control(connected to the 120 mains) for variable control.  Just set the pack to full throttle & adjust the train speed accordingly with the dimmer. A fan speed control works a little better. I have used the slide type dimmers & fan speed controls satisfactorily, some of the dial types work OK too(although for the fan controllers, the dial works backwards - full CCW is high, CW is low).

Robs idea would work as well.  how ever id lean more towards a fan controller than a dimmer ...  the newer LED and CFL rated dimmer may work ok....

Yes, generally the more it costs, the better it will work.

Rob, a bit of clarification if you don't mind.

Would the dimmer not simply be inserted inline between the power and the track, much the same way a protective fuse would be inserted.  Not certain if your reference to 120 volt was driving at that.

Thanks Rob and Ryan for the suggestions.

Ireland posted:

Would the dimmer not simply be inserted inline between the power and the track, much the same way a protective fuse would be inserted.

No. It would have to be on the 120v side. As if you were plugging in the pack to an outlet controlled by a dimmer.

It won't work on the secondary side for two reasons - 1)it needs AC, not DC... & 2)the triacs need 110-120.

Rob, thank you again