I'm stuck at page 69 - MotorTest4wd.ino.
The sketch is uploading and the 4 motors are running.
Motors 1 and 2 are running about 1/2 speed that of motors 3 and 4.
At the motor's 1-2 pins, I measure 2 volts and 4,1 at motos 3 and 4.
I didn't change the frequencies given in the sketch.
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