Monday, June 05, 2017

dimmer

A few days after putting the bunk bed up for the boys, I installed some LED lights on it. Some time ago, the knob on Anders's dimmer switch fell off, and I couldn't find a replacement knob. I could have just replaced the dimmer innards, but I never did like the cheap dimmer switch, because almost all of the useful dimming range was in a few degrees of turning, making it hard to adjust the low end of the dimming. I've had it in the back of my mind to fix this by making my own dimming circuit, and finally got around to it.


Here is a prototype of the circuit. I wired a rotary encoder to an microcontroller, and futzed with it until I could use it to dim a single LED.


I then switched everything to a bit of strip board, using a smaller microcontroller, and adding a MOSFET that allowed me to switch the 12 volt power that the LEDs on the bed use.

Saturday, May 27, 2017

End hunger!

The mother of one of Anders's classmates arranged an afternoon of volunteering at the SF-Marin Food Bank.


Along with the other volunteers, we packed 38,500 pounds of corn.


May is the month of the Bar Association of San Francisco's annual "Raise the Bar" food drive, in which Keker, Van Nest & Peters participates. So Anders and I were decked out in KVP t-shirts.


Anders and his classmates were enthusiastic volunteers.





Wednesday, May 24, 2017

just venting

The ducting that runs from our dryer to the outdoor vent has always been a bit of a problem. It would fall off at times, and was in pretty poor shape generally. This is because whoever installed it used semi-rigid ducting, which is not ideal for a dryer vent. Here's what ours looked like as of yesterday (and it looked much like this nine years ago, when we moved in).


After the old ducting fell off the dryer and, due to the horrible condition it's in, I couldn't get it back on, I finally decided to replace it. Two trips (don't ask) to Lowes Home Improvement later, we have rigid ducting in place. Hopefully this will reduce the amount of trapped lint that I need to clean out every year.

Sunday, May 21, 2017

Friday, May 19, 2017

Portola library

The Portola branch of the San Francisco Public Library is currently featuring artwork from the San Francisco School, the Alta Vista School, and E.R. Taylor Elementary. The SFS contributions include art from the kindergartners in Soren's class (as well as from the second and sixth grade classes). Soren's class made art inspired by The Big Orange Splot.



Here's a bigger version of Soren's contribution.


And here is a bit more of an explanation of Soren's class's project.

Wednesday, May 17, 2017

Open sesame!

We have a keypad on the garage door trim that lets us get into the garage. It chews through batteries, so sometimes when I need to get to my car I find that the door won't open, and then I need to go back up and get the garage door remote. But now, so long as I have my phone, I can open the garage!


This is the magical circuit that lets me do that, neatly attached with velcro to the side of the opener. Inside the box, the parts are attached to plastic standoffs that I've glued to the inside of the box with a glue gun. I've also used the glue gun here and there for strain relief and to seal cuts I made in the sides of the box to let wires in and out.


This is the part on the right. The knotted cord is from a 5v charger (I chopped off the micro-USB plug). The other three wires are 5v (red), ground (black) and signal (yellow). The bit in the middle is a bluetooth low energy (BLE) development board, which I've attached to a bit of strip board with a socket so that I can easily take the BLE board out for reprogramming if necessary. I programmed the board with a lightly modified version of some code someone else developed. I used the mobile phone app that this other guy wrote as is, other than changing the "secret key." All communications between phone and the BLE board are encrypted.


I tested the BLE board with an LED on a tiny breadboard standing in for the garage door opener.



The final piece of puzzle is taking the signal from the board and using it to open/close the garage door, which is accomplished with this relay. The output of the relay is wired to the back of the opener, along with the wires for the hardwired button in the garage, and the wires for the wireless receiver for the keypad on the outside of the garage. The entire project is encased in a plastic box that I bought on Amazon.

Sunday, May 14, 2017

Happy Mother's Day!

Anders made morning tea for Sigrid, and then joined her for a cuddle. Soren felt left out, so joined (along with his red zinger tea).


We went over to Peggy's house for lunch and afternoon fun. Here Sigrid is with a tshirt Patrick got for her.



The cousins played some ping pong. Soren's serve could use some work.

Saturday, May 13, 2017

farewell, and hello again

Anders, Soren and I went to Golden Gate Park for Patty Corwin's retirement party. During her tenure in the San Francisco School kitchen, nearly 1 million lunches were served!


Linda Louie, who used to be North Class teacher and who retired after Anders's kindergarten year, was there, so I managed to snap a pic of Linda with Anders.

Friday, May 12, 2017

A Tale of Two Guinea Fowl

Soren's guinea fowl (made this year) on the left. Anders's guinea fowl, from three years ago, on the right.

scientist

The third-grade had a unit on teaching, where they each taught something to the rest of the class. Anders taught about how octopuses managed to camouflage themselves. Today, the third-graders were to come to school in costumes loosely related to their topics, and then they each presented a fun fact on their topic to the second graders. Anders dressed up as a scientist—as a biology PhD, in particular.

Sunday, May 07, 2017

Camping with third graders

We went camping at Memorial County Park with Anders's class this weekend. Our coldest class camping trip yet!




For dinner on Friday, we picked up some kimbab, lettuce, cooked rice and marinated bulgogi at Kukje Market on our way to the campsite, and opened up a bottle of our rehearsal dinner wine, to mark the day of our tenth anniversary, which we celebrated the weekend before.

Wednesday, May 03, 2017

sprouts

Mesclun, soybean, carrots.

Sunday, April 30, 2017

happy birthday!

Anders had a joint birthday party with Noah again this year, this time at Linda Mar beach in Pacifica.




The weather report had us worried a bit, but the day turned out beautiful!






Friday, April 28, 2017

lemons

When we moved into our house in 2008, we planted lime and lemon trees in big pots. The lime tree did fine, but the lemon tree has never been a happy camper. We finally gave up and started over with a new lemon tree. The sad news is that it can take several years for a lemon tree to grow large enough to bear significant fruit, but hopefully this time things will turn out better!

10th Anniversary Celebration

We got away for a couple of nights to celebrate our 10th anniversary at Timber Cove Resort. Sigrid secretly called ahead and arranged for a chilled bottle of bubbly and a cheese plate.


Timber Cove is north of Jenner on Highway 1. Very scenic. Also very windy.



The rooms are cute, equipped with a gas stove for heat, and a record player (!) for entertainment.


Our room had an ocean view.


It was a great spot.




The grounds just behind the resort are beautiful.





There were tons of raptors riding the thermal lifts.



Just to the north of us we could see a small waterfall, but when we tried to hike closer, we found that it's on private property.


On the south side of the resort, you can see Timber Cove itself.


The neighboring property to the south is a campground with a boat landing. The campground has a single vacation cottage (the brown shack) that must have a fantastic view.


This waterfall is fed by Timber Cove Creek, and runs to the ocean along the edge of the boat landing.



Out behind the store at Stewart's Point.


Hiking to the Pygmy Forest in Salt Point State Park.


Kruse Rhododendron State Natural Preserve.


Stump Beach Cove.




Old school gas pump.


Yoga army men.


Posing with a warning sign for the gas stove.

Ten years is just the start!