  The excess noise factor and the aging characteristics of 16 Hamamatsu R11283
photopentodes have been tested. These fine-mesh phototubes are to be paired
with pure CsI scintillation crystals considered for use in the endcap
calorimeter of the Belle II detector. The average excess noise factor was found
to be $1.9 \pm 0.1 \pm 0.4$. The electronic noise of a custom preamplifier
produced by the University of Montreal was found as a consequence of this
measurement and was $1730 \pm 33$ electrons, in agreement with previous values.
On average, the gain$\times$quantum efficiency was reduced to $93\pm3$ % of the
initial value after passing 7 C through the anode. This corresponds to 70 years
of standard Belle II operation.
