[Elecraft] Yamaha CM500 bias batteries durability

[Jorge Diez - CX6VM]

hello,

how long a pair of AAA batteries will last in the bias of the CM500?  Will
be enough for a 48 hours operation in the contest?

I need to use the small black box with the 2 x AAA batteries to connect the
CM500 in the DXDoubler.

73,
Jorge
CX6VM/CW5W