I like my Sears 16.8 volt drill kit with two batteries but my charger
has gone south. It works fine when the batteries are only slightly
discharged but if they get too low, it won't work. The cost is

I opened it up and there is a small circuit board with 6 or 7
components on it, and none are marked. One device gets hot and the
charging light goes out so I suspect this device has partially failed.
I can cool it and it charges the batteries longer but I'd like to
replace the circuit with something else. Any ideas?