I have always run (many years) my Elecrafts at 15.6v .

There are a couple 15 V zener diodes across the supply line to provide protection (BZW50-15). They are specified to conduct less than 1 mA at 16.6 V, so 15.6 should be safe. However, Elecraft specifies 15.0 max.

73,

Scott K9MA

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Scott  K9MA

k9ma@...