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Chapter 2
Theory of Operation
General
The resistive element, in these dry Termaline Loads, is individually selected for its accuracy, and enclosed in a heat
sink housing. The housing is specially contoured inside to
provide the load with its unusually low reflection characteristics throughout its entire frequency range. The housings
for the 25, 50, 100, and 150 Watt models are deeply slotted
and painted black with a lusterless finish to improve their
heat dissipation. Models 8173 and 8431 are fabricated with
sheet metal fins to more efficiently meet their higher heat
dissipation requirements.
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