Hi Duane,
<< Icom IC-756ProII...An internal heatsink, - why put the single largest and
most variable heat generating source's heatsink inside the radio? >>
The entire heavy, die-cast light-alloy chassis of the IC-756 family of
radios (the IC-756, 756Pro and now the 756Pro II) serves as heat dissipator.
Heat-generating components such as the PA output and driver transistors, and
voltage regulators, are thermally coupled to the chassis. A small, quiet fan
provides supplementary cooling as needed (the fan is thermostatically
controlled.) I, for one, cannot hear the fan unless I place my ear against
the vent slots on top of the cabinet. In normal SSB operation at 80 to 100W
PEP output, the radio cabinet gets just warm to the touch.
This construction and packaging technique has a redoubtable (and
fascinating) pedigree.
http://www.qsl.net/ab4oj/icom/fam/fam.html
Best 73,
Adam, VA7OJ/AB4OJ
North Vancouver, BC, Canada
http://www.qsl.net/ab4oj/
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