But, you probably already knew this.

As for why have a locking gas cap that doesn’t lock, well, it’s very presence my deter some people from attempting to siphon gas (“Drat! It has a locking gas cap. We’ll try another vehicle.”).

Plus, with the retainer, it’s less likely to be lost than a non-retainered cap, which makes it much better than a rag (Can you say “Rolling Molatov Cocktail”?).

Dave

My dad did a bus conversion when I was a kid (late 80′s). I don’t remember many details but it was originally a 64 passenger school bus and had been painted dark blue before we got it.

I’d half planned to make the beacon into an “Is it safe?” indicator for the toilet at work. (Too many blokes all in the one office…)

I’d thought to use one of those battery powered LED dome lights as the doner case, the sort when you push the dome in to turn it on/off. Then I’d have my circuit “spin” inside the dome for 3 minutes, with each additional trigger adding another 30 seconds or so until enough time had passed for “fume dispersal” after which the circuit enters sleep mode.

I never quite managed to build it though as our baby came along and life changed dramatically.

RE: the bus blog. You could always ask people if they read both blogs? I’ll bet there’s a lot of lurkers!

If I do come up with a use, I’ll probably want it brighter. It’s not easy to Charlieplex with transistor drive, is it? I’d probably end up having to use some driver IC — and then it’s not really your slick, minimally driven beacon any more.

Ooooh — maybe a rotating beacon inside the bus to indicate some kind of emergency condition or power-down, like something from “Out of Gas”.

As to the detail in my writeups, it’s a matter of taking photos as I go, and the photos jog my memory. Things like specific voltages and currents I’ll often record directly into the blog instead of writing down on paper; but the rest is just out of my head.

I’m glad you enjoy it! I wish I had a good way to know how many of my electronics readers are subscribing to (or becoming regular visitors of) the bus site.

The camera flash idea wasn’t originally mine, there’s an instructable. But I made the blog post because I was so fed up trying to find any info about renovating NiCad packs that you didn’t have to pay for sight unseen. It is a nice use though because as you say the voltage is reasonable high but the current nicely limited. Wouldn’t want to put my tongue on it though…

Love your site by the way. I’m always amazed at the detail you put into your write-ups. Do you use a voice recorder like a TV pathologist? Or do you just have a great memory.

I remember seeing your lighthouse circuit before and I just watched the video again. That’s really nice! I need to find someplace to use that so I have an excuse to build one.

Also love your camera flash method for NiCad rejuvenation! I have a number of NiCad packs that could use dendrite removal, and the camera flash is a really clever way to charge up the high voltage yet limited current for safe removal. Very nice!