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The original fsu board was tied down only on the edges by that black
plastic which was clipped by some small fins of the aluminium radiator .It
did have a thermal paste .i also used a paste .
The +12 i took from a main +12 and used a 2.5 amps fuse .
The transistor i think disipates about 50w to 80w of heat at low speeds
that makes the heatsink to small to dissipate that heat and the airflow of
the blower at that speed is too little.Its true the transistor is made for
250 degrees but lets be true they dont make like they used.

The heatsink of the unit needs to be where air can circulate past it. The
fan is a good idea. I am not sure how the transistor is fastened to the
heat sink. It needs to make good mechanical contact with it.

When you use the thermal paste just use the smallest ammount you can. The
paste is not really that conductive of heat. It is just beter than air.
You want the transistor to make good mechanical contact with the metal of
the heat sink. There are very small inperfections in the metal that has air
voids in it. The object is to just fill the air voids. Too much paste is
worse than none at all.





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