Stan’s Obligatory Blog

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2/7/2014

More electronics hacking

Filed under: — stan @ 7:06 pm

I recently found out I had some stupendous number of ‘reward points’ on my credit card. I had a look at what I could get with them, and I got this. It’s a little weather station, complete with an outside temperature sensor. So I set it up, and it works well. The only downside turned out to be that the outside sensor eats batteries. A pair of good AA batteries would only last about two weeks in it, which seems pretty pathetic for something that you’re supposed to be able to just set up and leave, like a clock. So I started thinking about what I could do about that. Since I’ve done things like this before, I figured I could rig something up.

One possibility might be to just put more or bigger batteries in it, so that there’s just more power behind it, and they wouldn’t have to be changed as often. But then I remembered that I’d found the remains of a little solar-powered flashing warning light after the wind storm in 2011, and it had two AA-sized batteries and a little solar panel to recharge them. So I thought I might be able to rig something up to have those batteries run the outside sensor, and set up the solar panel to recharge them every day.

The instructions for the weather station unit say specifically not to use rechargeable batteries in it. I think that’s probably because it’s a relatively high-current use, and rechargeables just don’t hold as much as regular batteries. But I did some tests, and I found that the unit could run just fine on a pair of NiMH rechargeable batteries. It just wouldn’t last very long. So it was time to rig up a charger.

I had to make some little wooden fake batteries to go in the battery compartment of the sensor, since it seemed that it would not run if I just hooked wires up to the battery compartment contacts. It seems to want some physical pressure on the contacts to work. So I made some fake batteries and I just ran wires out of it to an external battery pack.

Once that was working, I got the little solar panel and a diode and hooked the whole thing up with alligator clips, and I set it up on the window sill. I got it to work there, and even inside the window, I got a good 3.6V off the solar panel. So it charged the batteries whenever the sun was shining. I left it running like that for about a week. After that, I moved it all outside and set it up there with the batteries and and wires inside a cardboard box, and the solar panel on top. It ran fine for a week, so then I made it slightly more permanent. I put the sensor back on its bracket under the garage roof overhang, and mounted the external battery pack underneath it. I ran a wire across to the south side of the overhang on the garage roof, and I put the solar panel there. And what do you know? It works.

It’s been running on the NiMH rechargeables and solar panel for over a month now, and it’s worked flawlessly. On the other hand, I noticed something else annoying. I’d thought that the indoor unit was just a passive receiver for the signal from the outside sensor, but apparently they must talk back and forth. And because of this, the inside unit eats a pair of batteries about every 2-3 weeks, too. This is annoying, both because of the expense of the batteries, and also the fact that both units need to be powered off and reset to change the batteries, even if only one is being changed. It’s a Pain in the Ass, and it also will cost on the order of $20 a year for batteries alone for just the inside unit. So I went looking and found a little 3V plug-in power supply for $7.99 online. I don’t know what it’s supposed to power, but that doesn’t matter. I just clipped off the plug at the end of the wire, soldered some wires onto the contacts inside the battery compartment, and hooked it all together. And it works.

So now I’m set. The inside unit runs off regular house current, and the outside unit is running on batteries, but they are getting recharged by the sun every day. And it was a fun little project.

2/6/2014

A vertical kilometer attempt

Filed under: — stan @ 7:18 pm

I went downtown this evening for some more fun and frolic on the Aon building staircase. My friend Morgan was going to try for a vertical kilometer this evening. That’s five times up the practice course from 4 to 55. I did this here last year in my preparations for the vertical mile climb. I knew I was going to get there a bit late, so I said I’d pace her for the final ascents.

As it turned out, she got there a little late, and only had two laps in by the time I got there at 6:00. So we headed up at a slow, but steady pace. We ended up doing that twice, and then she decided that she’d had enough at four laps. There probably wasn’t enough time for a fifth anyway, but if she gets there closer to 5:00 to start, the vertical kilometer is in reach.

2/4/2014

Still feeling my way up the stairs

Filed under: — stan @ 9:34 pm

It’s Tuesday, and time for yet another assault on the Aon building staircase. My back has been worse this weekend, but still nowhere near the levels of pain I was having back in January, so I thought I’d make the attempt.

I got there relatively early, and I started up the stairs at my ‘moderate pace’ of 4 1/2 floors per minute. This time, I was able to maintain that pretty much all the way up. And today was the first time since last year that I did the 51-story climb in under 11 minutes. And it didn’t hurt my back, so I guess that’s all right.

I went up a second time, just taking it easy. I turned it up a little bit for the last few floors, since I saw that I had a chance to get to the top in under 13 minutes. After that, I went up a third time, just because I didn’t feel bad. Nathan was there, so we walked up together, talking and just taking it easy.

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