David W. Body 🇺🇸 🇺🇦

More fun with the Metro Arduino board, which is supposedly playing back an infrared signal recorded from a remote control. This circuit sends pulse width modulated output from the Metro (yellow) to the base of a transistor, which pulls the anode of an IR LED low (blue). It's definitely transmitting something, since I can receive it with a Flipper Zero, but I couldn't get it to control my TV.

Edit: the blue trace is actually something else. See below.

#electronics #arduino #oscilloscope

Later, on an walk through the woods, I realized that sine and cosine are their own fourth derivatives. This is not exactly news to mathematicians, but all of a sudden it was like OF COURSE they are! (3/n)

#math #learning #trigonometry

Most of the math I know beyond "business calculus" is math I picked up in grad school (economics) or taught myself later. I'm constantly reminded there are gaps in my knowledge. For example, trigonometry doesn't come up much in economics or statistics. (1/n)

#math #learning #trigonometry

Curious Marc runs Microsoft Basic on an Altair 8800. As Marc says, "[Bill Gates] really had to be a visionary to perceive that this was going to be the future of computing."

https://www.youtube.com/watch?v=TxU_3dEJ2nM

#retro_computing #vintage_computing

#introduction

I'm a professional #software developer developing mostly custom database-backed web apps (#rubyonrails, #django, etc).

Currently applying #machine_learning to video data from zoos & aquariums. I also do some #data_analysis & #data_visualization using #rstats, #python, #julialang.

Lifelong learner currently working my way through a textbook on advanced linear algebra.

Other interests #climate, #economics, #fitness, #math, #open_source, #politics, #probability, #running.