I'd be interested in how you upgrade the rectifier for this upgrade. I'm assuming you remove the on-board one and go with a chassis mounted one. What about the capacity of the driver FET? Do you consider a heatsink on that as well?
Originally Posted by GGG:
Fred, Which MTH model? If your willing to take a risk, I will back it. I was contemplating doing that upgrade with just a PS-2 board. I would replace the rectifier and the motor diode with the larger higher rated and heatsink to the frame similar to 1 Scale.
The board can handle the lights and 2 smoke units. I think the 2 extra motors can be handled too with an upgrade on the rectifier. Experimental, but yes saves you a lot of cash. The veranda turbine or propane as an example are good fits with all 4 motors in the same chassis. You can e-mail me if your game. G
It's MTH 20-2124-1, the Premier Proto 1 gas turbine with three segments. I had been thinking of just using a CC, removing the two motors in the turbine segment and pulling the whole thing with the front segment. No sound. Unlike a lot of folks, I don't have a huge layout or a ton of rolling stock.
Your proposal does sound interesting!
Fred
That would be an option, either TMCC or PS-2.
Yes to both John, This would be similar to the #1 gauge boards MTH has. Though they don't heatsink the Motor FET, just increase the size of the flashback diode. G
That's pretty easy to do, just pick up one of the 15A stud mounted bridge rectifiers. Interesting thought, I might do that instead of a slave kit for an A-B-A with four motors.
I would only do this with a unit that has 4 in the same chassis. I am not sure how the tethers would handle it. I remember MTH tech talking about that at one point. G
One way to find out! 
The tether is designed to handle motor currents, but I don't know about the diesel tethers, might have to improvise.
Yes but not with one load close and the other 2 cars away. Most steam just 10" away. Would be interested to know though. Can't do it on a customers engine. G
I agree, I'd never test this on someone else's engine, at least not unless they thoroughly understood that is was "experimental".
I happen to have an A-B-A set of F-3's that are PS/1 that I'm planning on upgrading. Maybe they'll be the first to receive the test.
Couple ways to skin the cat. Feed the top board motor lead pins but not AC pins. Feed the 9VDC signal. Feed the bottom board (it is full rectified anyway) but still remove the AC to top board.
As I stated this is motor sounds only You could feed track voltage AC to the top board. And use separate horn/bell button. So it is doable based on trying to keep the PS-1 specific sounds while running TMCC for control. G
GGG- have you made progress on this? Almost dying to know. Have a triumvirate of PS-1 AS-616's that I want to operate in the TMCC environment while keeping the PS-1 Baldwin prime mover sound.
No, backed up on repairs, train show and honey do list. G
Yeah, the honey-do list can be a killer.
