I have been wondering which way the fans on my TS-930 should be
blowing. Should they take the ambient air from outside and blow
it on the heatsink, or should they be evacuating the inside air
in the vicinity of the heatsink and blowing it out? I have been
restoring the unit and both fans required replacement.

I've surfed a number of sites on the subject but can never get
a definitive answer.

Thanks in advance for any assistance...

de Irv, VE6BP