Calvin vs bike

Prepping for a long ride

2nd week of September, my work will move from Dexter to Ann Arbor. This takes me from a 12-15 mile trip to a 25 mile one way trip to work.

I've moved back to my hybrid/foul weather/winter bike - it's upright and until I feel confident on the roads there, I'd prefer an upright stance. I've moved my best lighting system to it, gotten fresh batteries, and I just ordered a pair of Schwalbe Marathon Plus tires. They're kind of expensive but they supposedly are nearly bulletproof and wear for many thousands of miles.

Book finished: The Blind Watchmaker

The Blind Watchmaker by Richard Dawkins


Good grief this book was tedious. For my own reading I would have given it two stars, but I boosted it to 3 because it is, I guess, an important collection of facts and relevant arguments.
If you expect to be arguing with creationists about evolution, this is an excellent resource. For me, he's preaching to the choir, and I don't argue with creationists because I don't like to waste my time.
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[Dragonfly DIY] Laptop mainboard - ALMOST right

My last post was about a laptop mainboard that I dropped in, and that it only had one thing different - a different connector for the feature buttons.

Well, then I noticed that the touchpad buttons didn't work. And it didn't think there was a battery plugged in. And the LEDs up front (power, battery, wifi) weren't lighting.

I opened it up again, and found that there were no switches installed on the mainboard for the mouse. I surmise that it was for a slightly different model that had buttons in the touchpad (there is also a populated connector on this mainboard in the right place, which is probably for that purpose). So I got the hot air out and removed the switches, and moved them. I also desoldered the LEDs from the old board and moved them (no mean feat - they are 0603 LEDs). I plugged in enough to power up, and no luck. The LEDs didn't light, and the mouse buttons still didn't work.

I compared the boards and determined that the mouse button switch leads go through a couple of 0603 100 ohm resistors. One was still on the board, so I moved that one. The other one was probably lost when I swept the switch off with the hot air, so I put in a 330 ohm resistor which I have on hand. This worked.

The LEDs, probably a similar story because I noticed that it had LEDs already in place elsewhere on the board and those were working. I just drilled three holes in the top of the laptop to let the LEDs shine through and covered it with tape.

The battery - that was another story. Turns out the battery connector was about 3mm shorter on this board than the other one. I did manage to remove the connector from the old one and get it on the new one. This took over an hour. Lead-free solder is a pain in the ass when desoldering large connectors with through hole physical stakes. On the old board, I ripped the via rivets out while desoldering, so I was super careful on the new board. I tried hot air on the old board first but it was just not working and I decided if I was going to have to use other means on the new board, best to practice on the old one first.

Anyway, that's all working now, the LEDs are shining through the lovely bodged holes drilled in the case, the battery is charging, and the mouse buttons work.

I would NOT have been successful at this stuff without the microscope that I bought last week. The parts are just too small for my eyes. I think they're probably too small for anyone's eyes when you consider you need to examine the solder after your work is done. Maybe you could do it with a 10X loupe but I'm happy to have the microscope.

My tweets

  • Thu, 21:27: I should know more than one 3D modelling program (currently I just use OpenSCAD) so I guess I'll learn Fusion 360 - all the cool kids are.
  • Thu, 22:17: I bought a copy of Simplify3D and have been playing with it. I don't think it's actually printing better than Slic3r. Am I wrong?

[Dragonfly DIY] Laptop repair

Just a quick heads-up - we had a laptop die in our household a few months ago, and didn't have time to mess with the repair so we just bought a new one. Last week I started messing about with the repair and spent several hours looking for a crack in the circuit board or a bad connection to a component (would only power up if pressure was applied to the board).

After a couple of hours of this, just out of curiosity I checked ebay to see what a new mainboard would cost. Turns out, $30. Well to heck with fixing the old mainboard then. I'd already wasted more time than that.

2 days later, the mainboard arrived. It was new in box, slipped right in with one exception - it had a 0.5mm pitch connector instead of the 1.0mm pitch connector in one place but it was just for the options keys. I ordered new connectors off eBay, it'll be a few weeks (China) for $3 for 5 of them.

Moral of the story, check the prices for all the options before spending much time on a repair. I just assumed mainboard replacement would be uneconomical since the last time I tried to buy a laptop mainboard they wanted more than the cost of a replacement laptop. These days if the laptop is more than 2 or 3 years old, likely there are repair depots liquidating excess inventory for a song.