Sounds right. Makes me want to dig out the manual/instructions for the battery minder that I use on the motor cycles.

I took a look at what I use. I have the Hobbico 12 volt wall wart that puts out 12 volts 600ma. I use that most of the time giving my fieldbox a good overnight charge and that lasts a long time.

I have used my Schumacher Battery companion that I keep my motorcycle battery charged but it puts out 12 volts at 1.5 A. http://store.schumachermart.com/sem-1562a.html But the good thing about the Battery Companion is that it will switch to "float mode".

Both have worked well for me. The negative reviews are usually when somebody tries to bring back to life a battery that is shot.