One day I smelled something burning and scrambled frantically, as I thought I had an electrical fire starting within the walls of my house. Turns out it was my wife's make up mirror sitting innocently on the edge of the bathtub. The sun hit the mirror just right and beamed a focused light onto a plastic container. The lid of the container was half-melted and smoking badly.

I hadn't thought of that angle. Maybe also the cage surrounding the plants results in an increased ambient temperature affecting the growth. Wind currents changed. So there's three variables to control and check: metallic substances, temperature, and airflow (with airborne entities).

Agreed, users would screw up the knob - that's why I said the knob maybe should be hidden. It's there only for "backwards compatibility". Going forward with new products and the new standard, we lose the knob, lower costs and all are happy. For machines running less than the set voltage an internal voltage regulator can adapt, since the voltage should be close. Best to use the standard voltage however and not transfer any extra electricity into heat.

One knob to set the voltage, probably between 15V and 20V. Maybe we hide the knob so it doesn't get adjusted accidentally. n amps of current max. 2.5mm or bigger jack size. There, specs all done. Build 100M of them and cut me my cheque.

They were able to crack a 1024-bit key in 104 hours using 80 slave workers. They also say the cracking app should scale linearly with the number of workers. So 800 slaves would mean on the order of 10 hours. That is pretty scary. Newer commercial apps should be using at least 2048-bit keys. I am not sure how that affects the results.