I am interested to know why MTH changed from the 8.7 volt system. Anyone know?

o gauger;

I think if you re-post your question on the DCS board, you will probably get quite a few responses. That's where most of the DCS experts hang out.

I am sure Barry has an idea why they changed.

Thanks folks, I have done just that.

Probably because they found cheaper ways to make the circuits and those elements required less voltage. Not to mention everything electronics is trying to go to less and less power consumption, which eventually means circuit voltages will go even lower. Things already work in the millivolt and microvolt range. How else would the battery life on an ipod touch be so long (ignoring the fact that today's microprocessors go into sleep mode, but that's besides the point).

Saves space also, and since MTH was prepairing to get into the HO model locomotive market, space saving was/is VERY important.

Te battery went from 8.4 volts to 2,4 volts when the PS2 board's processor went from 5 volts to 3 volts.

FYI, the processor in the TIU went to 3 volts in Rev. I models from 5 volts in previous models.

They kept at first the 9 volt design of the QSI PS1 loco. They probably had a big stash of 9 volt batteries laying around from PS1 production. The 9 volt type boards did not come apart and were not repairable as a practical matter. The lower voltage system is more state of the art and reliable, the higher voltage simply is not needed. 5 volt super capacitors are also made to preserve memory in such circuits so even the lower voltage system does not require a battery if the design were altered a bit. For some reason MTH retains the battery.

Dale H

The reason for the change from 9-volt to 3 volt is you get equal or more processing with less power in a smaller volume of less weight. The change is driven by the electronics industry.