relays are for mechanical On/Off control of high power using microcontroller.
transistors are for analog variable power control using microcontroller
“If you are switching DC motors, solenoids, or other high-current DC devices which create motion, it’s better to use a switching transistor than a relay.”
“The ideal way to control a motor is with an H-bridge, which is an array of transistors that lets you control not only speed but also direction.”
DC Motor
Got a private lesson from dear Jeff on the power supply box and discussing how the transistor works in a circuit (as well as what the larger more physical form of a transistor looks like). We got my junk shelf motor running as well as the strong push/pull mechanism whose name I forget.
I have the motor hooked up to the Arduino reading from the potentiometer for speed. This is the DC motor I found on the junk shelf. I notice that the potentiometer successfully slows down the motor as I turn it, but only if I send high voltage (cranking the potentiometer) first. If I go from LOW to Low-ish, it won’t turn; I have to get it spinning at top speed first. Why?
DC Motor with H-Bridge
How to get this on the board? Do I need to solder on the double sided header pins first?