my ni-hm charger stop working.i have other with a little diference.about 200mah less than the other..

my ni-hm charger stop working http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2969. i have other with a little diference 24V with capacity < 1600mAh. have all the specifications like the first one but with this diferece 1800mAh vs 1600mAh. also the 1600mah battery was sopouse to charge two parallel 12 Volt 12 Amp Hour lead acid batteries.is posible to try this without damage?i believe my ni-mh charger was broke because i remember when go from my hands to the floor.when i try to charge the battery i hear a little noise from the charger.it stays red for hours.is easy to test and repair a charger.ok i know the price is around 40 bucks.some expert advise please.thanks for the attention.