I'm rather new at this, but I've purchased an RC car and me and a friend are trying to remote control it via arduino. THE ARDUINO ISNT CONNECTED IN THIS IMAGE, but it connects through the resistors into the base pins of the transistors.
I destroyed the board that came with the car, so I've recreated something similiar on this breadboard. It consists of 2 H-bridges made up of NTE2504 transistors. The arduino pins connect to the BASE of the transistors via 2 680 OHM resistors per pin The whole thing is powered by a 6v lithium battery. The steering uses a regular motor. When the steering motor is powered, it doesnt seem to have enough power to turn all the way, but when the battery is connected directly to the steering motor, it will turn completely. Is it possible the transistors arent fully saturated? did I do the math wrong? I calculated that a 2 500 OHM resistors would allow 20MAH through each pin., so 10MAH per transistor.
I checked the battery, its at 7 volts and plenty of current.
These are high gain transistors (800-1600 HFE) so I assumed that would be plenty. The motors pull 700-800MAH each, so 10MAHx800= at least 1600 should be plenty Is there some kind of voltage drop going on? I'm lost.
TL;DR THE CAR WORKS, but the voltage seems to drop through the circuit.