He was talking about our trainer boxes, though. The trainer incorporated a power supply (+5v, +/-12v, 1-15v variable, plus 6.3 VAC I think), a signal generator (sine, square, and triangle), breadboard, and eight debounced toggle switches and LED indicators. It was a nice little kit for the electronics student, and as a bonus, of course we had to put them together ourselves. If it didn't work, we were supposed to figure out why and fix it, as he pointed out.
Today was a very busy day. I had to do some shopping, then took care of some business; once that was done I bought string for the trimmer (since I could not find the string I have). I used up several feet of string getting the damned weeds whacked around the bunker, including knocking back the raspberry canes that were encroaching on the front porch. When that was done, I got out the tractor and cut the grass. Then I hauled out the pusher to finish the job, only the pusher refused to run right. First it refused to stay running--ordinarily I press the primer three times, pull the cord, and it starts right up, so that was weird. Once I managed to get it to run continuously it would surge and choke, running very unevenly. Clearly it was some kind of fuel problem, or maybe the air filter was clogged.
Mrs. Fungus got home from work as I was coming in to get tools to figure out WTF was wrong with the damned lawn mower.
The air filter looked okay, though I knocked a lot of grass dust out of it; I could still see light through it. The fuel supply was fine. Spark plug was good. There was a thin twig stuck in the throttle linkage, but that wasn't the source of the trouble, either; I restarted the thing after checking each of those and got exactly the same performance.
Finally I decided I'd have to try pulling the carb and cleaning it. That was a bit of an adventure, of course, but all told it took about fifteen minutes for me to get it off the mower. Dug out the carb cleaner I bought way back in June of 2011 to clean the dirt bike's carb; I dipped everything I could in that stuff and then blew out all the passages with compressed air. Reassembled it, got the mower back together, gassed it up...it ran like a dream, and I was able to finish cutting the grass without incident. Which is good, because the carb is entirely non-adjustable, and if that hadn't fixed the problem I would not have known how to proceed. In fact, the only moving parts in the carb are the float valve, the float itself, and the throttle butterfly; otherwise it's just a bunch of precision holes and metering tubes.
Once that was done, Mrs. Fungus said she wanted Popeye's chicken, so I hied myself off for that. Having had only a PBJ all day, I was starving, and ate too much, but it was so good I couldn't help myself.
Now it's nearly time for bed, and because it's so nice and cool outside I do believe I'm going to sleep pretty well tonight.