Geeks making the world a bit better.

Entries from July 2009

Why I don’t develop for the iPhone/iPod Touch

The iPhone and iPod Touch are very interesting platforms for enabling technology. Touch, accelerometers, portability, radio, coolness; they’ve got it all.

But the rules of program distribution are so ridiculous that I can’t imagine playing by them. I want to give my apps away. And I want to do it without some faceless technician’s approval.

After you’ve done the work to develop your App they can reject it without giving any reason.

This recent post from Riverturn illustrates the problem though I’ve heard of many more cases like this.

Project Ideas for Wiimote Enabled Firefox

I’m thinking of things we can do with the nearly ready Wiimote (and Balance Board) capability in our Outfox extension. We can use the accelerometers, IR camera, buttons, and rumble. I’m going to list game/activity ideas so I can recruit some help.

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Crawl Space Humidity

I’ve been concerned about the humidity in my crawl space since we moved in. In fact, I wondered about it at our former house but never did anything about it. At the current house we’ve had some problems with water getting under the house in heavy rains but I think I’ve got that whipped.

I decided the first step was measuring the humidity under there so I bought a Honeywell TM005X Wireless Thermo-Hygrometer and put the remote unit under the house. I bought it back in January 2009 and boy was I shocked. The humidity seldom got below 75% even in the winter! As the summer came on and the humidity rose to above 90% I decided I had to do something. It is so humid down there that water condenses on the cold water pipes and drips on the floor.

Completing the plastic covering on the floor (about 20% was uncovered) did nothing. So I went looking for solutions. I found the SmartVent Crawl Space ventilator and after reading their convincing argument that you can’t dry under your house with wet air, I decided to purchase one of their vents. It cost me $315.

It arrived less than 1 week after I ordered it and I installed it the next weekend. I had never removed a crawl space vent before but it turned out to be a pretty easy job. Mine were installed with mortar which I broke out using a long chisel and a hammer. It took me approximately 1/2 hour to prepare the opening to receive the smart vent. The place I chose to install it had an electrical outlet nearby so I was set for power. I used clear caulk to seal around the opening.

I installed it on 20 June 2009. After 2 weeks my crawl space humidity is down to 77% from 92% on the day I installed it. I’ll make a table below to record occasional readings. It has been dry here since I installed it. That, no doubt, is part of the rapid improvement but since I’m not doing any sort of controlled experiment, I’m just going to report what I see.

The SmartVent appears to be well made and runs a clever algorithm. It has two muffin fans, a small circuit card, and a thermometer and humidistat positioned near the front grill. It uses these sensors with the fans off to sample the outside air. If the outside air temperature is above 42 degrees F, it runs one fan for about 15 minutes to pull crawl space air over the temperature and humidity sensor. It then compares the dew point of the outside air with the dew point of the crawl space air. If the dew point outside is lower both fans run to pull wetter crawl space air out so that it will be replaced (through leakage) by dryer outside air. If the outside air is wetter than the inside air, the unit waits.

My sporadic observation of its habits confirm that it is behaving as expected. I’ve seen it running continuously for the last few days while the outside dew point has been low but last week it ran much less because the outside air was very humid.

I’ll try to record some readings here so I can track how it does.

Crawl Space Outdoor
Date Temp (F) Humidity(%) Dew Point(F) Dew Point(F)
20 June 2009 68.5 92 66 72
4 July 2009 69.8 77 62 58
11 July 2009 69.8 81 64 64
19 July 2009 70.3 81 64 59

Note: On 14 July 2009 my Honeywell wireless hygrometer died and I replace it with an Oregon Scientific RMR500A. The calibration was clearly different. I calibrated the new one using the damp salt method.

I expect it to become gradually harder for the SmartVent to improve the situation under the house because as it lowers the dew point, there will be fewer times when the outside dew point is lower. But, I hope and expect it to be better than it was.

Big Words Interface Ideas

I’m thinking about the client-side interface to our Big Words project with the Center for Literacy and Disability Studies. Rebecca is making good progress on the server-side logic for the games, the instructive feedback machinery that is the essence of this approach. But we need a good looking user interface to keep kids coming back.

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