it is difficult to see because the waves are distorsionated about the inductance of the motor,but more or less i saw a different of voltage between the output and the wire parallel of 0.4V,with a power resistor of 0.5ohm,so tyhe current is about 0.8A,no load
so maybe when i use the gearbox this current will be higher,and my AO only can have 1A at its output,so i am sure that i am going to have a higher current, then this is why the AO is getting hot, i think
is there a way to don´t have this problem?