Slept in then met up with Melinda and Sunil and Torkel from her lab for post-lab-meeting brunch. Zazie is very tasty: ham and gruyere cheese, fried, covered with more cheese, and a fried egg. I stopped at sfDisplay on my way home to buy a display case for my coins and one for Melinda's apartment. These cases have ordinary picture hangers, rather than the permamounting anchors the others I bought had, but that'll be more fitting: coins are light and I'm a bit reluctant to poke 1/4" holes in the wall in SF. Back home, I've spent the last 5 hours pretending to be an electrical engineer. I did finally manage to make a sine wave, and pretty nice one at that (pictures forthcoming) and, passing it through two transformers, got 100v p-p from my 5vdc source. The purpose of this work has been to make a driver for EL wire, but I read today that EL wire wears out more quickly at higher frequencies, so I'm going to try to cut the frequency back (the sine wave is at 48kHz). My first attempt at a 1kHz circuit hasn't been so great: I get just edge spikes instead of pretty sine waves out of the transformer primary load. I expect part of the issue is that I'd sort of like a 10uF non-polarized capacitor for this task but such a thing is rare (caps that big are electrolytic and polarized). So, tomorrow I'll go back to the 48kHz circuit, be a good scientist and reproduce my results, and then instead reduce the frequency gradually, finding suitable parts as I do. I'll also just see what happens when I feed a 48kHz signal into the EL wire. Maybe it'll be okay with 48kHz if it's at a lower voltage level. Or it'll melt through my table. It'll be exciting to try.
Rest of the right: dinner, reading about glass over dinner, then glass w/ Melinda in an hour. Tomorrow: photograph glass (from tonight, two nights ago, and last week), more electronics, enough glass work to finish off the oxygen tank, and exchange the oxygen tank at Madco.