First off, are there any good tutorials to making a charger cracker anywhere? I can't find any... and second, what are the laws about N2O in PA? Is it over the counter? I live in Jersey where you can't possess it unless you're a f-ing certified medical doctor...
You can't charge a cracker. Once the nitrous is used to have to replace it unless you have a nitrous tank.
By charger, I think he meant the little canister. The cracker is the thing that 'cracks' it open. Sorry, OP, I don't know how to make one.