[Elecraft] Battery power problems.

[Stuart Rohre]

The problem could well be the age of your battery and its aging rise in 
internal impedance.  If it will not charge to 13 plus volts of a fully 
charged battery, it indicates excessive internal resistance/ age.

The fact everything cleared up on an AC to DC supply supports the battery as 
a problem battery.
If the battery is 3 years old, expect problems.   Most security companies 
and others relying on gel cells change them out in 2-3 years, even if they 
have not been heavily used.

Stuart
K5KVH