Kaman KD-5100 - Manual (Page 21)

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the cover plate for heat sinking. The calibration controls are located inside the unit and
the cover plate must be removed to access them. Removing the cover plate removes its
heat sinking function. Calibrating with the cover off and then reinstalling it will cause
enough of a thermal gradient to throw the calibration off.
12-1c1. Kaman’s solution is to use a cover plate with holes drilled in it for access to
the calibration controls. This plate is available as an accessory from Kaman. The
factory installed cover plate has a mica insulator epoxied to the inside with silicon
heat sink compound between the mica and the hybrid housing.
12-1c2. You may either obtain a calibration cover plate from Kaman or fabricate one
from 0.062” thick aluminum. Dimensions and location of the holes are shown in
Figure 12. Use a double thick layer of Sil-pad as an insulator. Although the heat sink
properties of the Sil-pad are not as good as the mica/heat sink compound, it is
adequate for calibration purposes. The hybrid is recessed in the case, this is why we
recommend two layers of Sil-pad, to ensure contact and thermal conductivity.
Figure 13 Calibration Cover Dimensions
(see page 11 for additional cover plate dimensions)