RE: Charging a lawn tractor battery for the field box
+1!
I have two of the Schummacher 1.5A 6/12V battery maintainers from Wally World. Perfect for keeping the flight box battery topped off during the flying season. During the winter, my ATV (aircraft transportation vehicle) gets very little road time, so I keep it on float charge, ditto for the garden tractor/mower battery.
At 20 bucks, these are a good investment!
While these units are rated at 1.5A charge rate, I've found that when hooked to a 7Ahr gel cell field box battery after a day at the flying field, they actually only hit about .5A, so no problem with the charge rate for our field box batteries[8D]
Pete