Laser spirograph

I wanted to build a project that would increase my experence with non microcontroller chips. So I picked one I know pretty well (555) one I faile with in the past (h bridge) and a new one (not gate.)
The h bridge and I had words once or twice and I have some projects I want done that use motors. So I set up two 555 timers to provide pwm and fed that to the enable pins for the h bridge. The direction pins are tide via the not gate and have switches. Motors are driven by 9v, and the mirrors are mounted on the end of the shaft.

Which reminds me,  don't cut CDs in the laser cutter.

I wired it all up and fired it up and blamn... it worked. Some call me presumptuous,  some a genius,  you can call me hip.

AM modulation with transistors.

So I'm an engineering student and I'm taking a communication class. (Not public speaking) and we were learning AM modulation. What does a maker do? Makes one.

I based it on the NJM#1496D. Since I was wanting a general idea of how it workes, I used general values for the resistors, and a handful of npn transistors (likely 3906 but defiantly npn)

The fundamental way it works is this, a differential amplifier is driven by the carrier. This is switched by a transistor with the message signal driving it and they are limited by a current mirror. The actual circuit is a bit more complex and is capable of biasing and such but that's the basics.