This is a photo of my BEST and ONLY charger that I now need.
for Ryobi, Ozito, Carbac repacked batteries up to 18V.
The 3rd terminal of the batteries must have a 10K thermistor connected to a battery negative case.
This AUD5 charger now charge my Ryobi (14.4V), Ozito (18V), Carbac (18V) batteries as they all have almost identical dimensions - sorry Max 18V.
With most people going Li-Ions, this excellent charger for Ni-CAD/NiMH can be very cheap to buy.
Silicon Chip also designed a DIY charger using the same temperature sensing principles.
Before I found this charger, I just used a mains timer with my lab. constant current power supply to charge those NIMH batteries
Before I bought the GMC drill I phoned GMC and asked if the charger is automatic, ie: goes into trickle charge when fully charged and was told definitely YES, but I doubt that it was. One day if I think about it I may do some tests on the chargers, I still have both. These days, for my two B & D drill batteries I use a count-down timer to be on the safe side.
Nothing but heaven itself is better than a friend who is really a friend. - Plautus