@gunrunnerjohn posted:If the FET shorts, you can get a lot of power, normally PV for PS/2 is around 20-22 volts. However, the 8 ohm load across it would drag it down a bunch, so I really doubt it had 72 watts, but more like half that. Still enough for a real smoke and flame show.
I've seen a similar thing when the smoke regulator shorts on Lionel TMCC or early Legacy, it dumps 18 VAC into the 8 ohm resistor. 40 watts on a 2W resistor is impressive for 20-30 seconds and then nothing. If it's a diesel with a plastic shell, it totally destroys the shell near the smoke unit. Steam just stinks up the inside of the shell, I fixed one for a club member, and years later you can still smell the burnt fiberglass smell.
All this talk of flames reminds me when I was a kid and stuck a screw driver down the throat of a Lionel turbine ….flames and smoke than poof………I was was disciplined not to do that again. But it was cool to see….
