I noticed the last shipment of PS32 boards had an addition. Apparently, MTH finally figured out that the FET's might need a little cooling help! 
The heatsink is an added feature that just appeared this shipment.
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Nice! How easy/difficult would this be to retrofit to previous boards?
Chris
LVHR
I suspect making the heatsink with the exact right dimensions would be the only tricky part. Of course, soldering to the tabs of the FET's without killing them with heat is somewhat tricky as well, I always had issues trying to solder the heatsinks back onto the older 5V PS/2 boards. Interestingly enough, the 3V PS/2 boards never sported heatsinks on the motor driver FET, not sure why this one was added.
Sorry John, that was limited run. MTH converted some of the ones made for #1 scale and soldered the rectifier on the board to sell excess stock. G
George, these were on all the PS32 boards I recently got. Are you saying these were for #1 scale and just "repurposed" to fill our orders?
There was a large batch of 3/2 boards intended for G-gauge using the remotely mounted bridge rectifier. They were modified to move the rectifier to the board for use in O gauge and Tinplate, however the rectifier on some boards was set too deep into the PCB so the heat sink has to modified to properly fit when mounted to a chassis. (No, I didn't do this, but I know who did).
The heatsink in question is on the motor drive FET, not the rectifier, so I' guess I'm confused.
The G gauge 3/2 boards have a heat sink on the FETs and a remotely mounted rectifier (so it can be attached to a BF heatsink in the loco). The boards were modified to mount the rectifier on the PCB for use in O and Tinplate. The modified heat sink I was talking about is the bracket that attaches to the rectifier. It may not fit correctly because the rectifier is set too deep in the PCB.
OK, so the heatsink on the FET was standard for the G-gauge, that makes sense. You switched gears on the headsink, threw me off, I get it now.
It's interesting as I recently used one of these and I had to make a custom heatsink because the standard PS32 heatsink didn't line up correctly, I didn't realize why, now I do.
I know who did it too? Look at the legs and you will see why there is an issue. PS-32 are not normally set all the way down to the step in the leg. They have insulator. G
Just my luck to get the defective boards. 
