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Most recent entry: 2014-07-23 00:00:00 -- Generated on 2014-07-31 08:48:24 by Rig3 0.4-440




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2014/07/23 Making a super cheap water/flood sensor
π 2014-07-23 00:00 in Linuxha
I wanted a water sensor for my water heater that would both alert me in the house, and as remotely when the sensor was tripped.

This is what it looks like:


I analysed how the DS10A worked, and due to sheer luck in its design, the wires going to the magnetic sensor turn out to be ground and signal, and the water sensor conducted enough current between them to allow triggering of the DS10A:


Wiring is totally trivial, you only need to use a 3rd wire connected to the plus from the 2 batteries, and it "just works". For extra credit, I wired a buzzer between signal and ground, and my water sensor passed enough current to allow the buzzer to run.

I used the Phantom YoYo High Sensitivity Water Sensor which was $10, but apparently you can get one that should work too from seedstudio for $3

The DS10A, I have a stack of, which you can sometimes find on ebay for cheap in bundles, and my house is already wired to receive those signals, so it was trivial to generate an Email and page from misterhouse when this sensor got triggered.

100_DS10A_Water_Sensor 102_DS10A_Water_Sensor 105_DS10A_Water_Sensor
2014/07/08 Simraceway/Sears Point Formula 3 - Stage 2
π 2014-07-08 00:00 in Cars
After doing stage 1 some months back, I went back to learn stage 2. I definitely got better with downshifting the 2nd day once I figured out that my foot was too wide and I was pushing brake and gas a the same time, preventing downshifts from happening. This was fixed by turning the brake pedal two turns towards me.





Here are some of notes of what I learned those 2 days:

  • faster upshift (barely get off throttle)
  • faster and harder transition from gas to brakes (same end pressure, faster transition)
  • Do not brake and gas, this prevent shifting
  • passing: When you are side to side but not quite for a turn, you must release the brake to win the corner since you cannot stop any more. If someone is trying to pass on the outside, you brake even more to leave them room to be side by side with you. The inside guy gets the apex no matter what, even if not wheel to wheel


  • And notes relative to actual turns:

  • carry speed into 2, do not brake so much and gas back up, just keep speed going up
  • lift before turning 3a, start turn and put a bit of gas more gradually (do not remove gas)
  • 4 brake early enough not to understeer
  • 5 flat out
  • 6 good brake on top but not so hard, light brake, coast, and early gas half way down
  • 7 brake 3rd cone, good brake pressure
  • 8 go faster and turn later so that I can connect 8a
  • 9a get on the brakes faster, be a bit faster turning the wheel from 9a to 9b, scandinavian flick
  • 10 flat out, shift before turn in 10 so that I'm not as sluggish in the turn
  • The 2nd day in the morning, I got a flat on one of my tires without knowing, which made the car very oversteery and before I knew it, I spun in the chicane and got to see why:


    This time we were running the full course and had slicks on the cars, so it was a good difference from level 1.
    We only had 4 people in our group, and one was close to a professional racer, so I didn't get too close to him. As a result our end times on the 2nd day were the following: our teacher Nico had a benchmark time of 1:38, our next best driver was at 1:41, I got down to 1:43, and the 2 other students with less experience were around 1:48.

    After driving, we compared our data acquisition to see what we were doing wrong or could improve:


    My last 2 sessions the 2nd day in the afternoon, my times were reasonably stable and in the down direction :)

    One before last session: 1:48, 1:48, 1:47, 1:48, 1:45, 1:48, 1:46, 1:46, 1:46, 1:46, 1:47, 1:46, 1:48

    Last session (with video offset): 1:45 ( 0:37), 1:45 ( 2:22), 1:46 ( 4:08), 1:45 ( 5:53), 1:45 ( 7:38), 1:44 ( 9:22), 1:48 (11:06), 1:44 (12:50), 1:44 (14:34), 1:44 (16:18), 1:44 (18:01), 1:43 (19:44), 1:44 (21:28), 1:44 (23:12),

    Here is a vid of my last session

    And for novelty purposes, a shaky video from google glass of an ealier session:

    On the way out, I got to watch Dorifto wednesday. That was quite fun to witness ;)





    2014/06/26 5 Miles of Thunderhill in an Elise with Golden Gate Lotus Club
    π 2014-06-26 00:00 in Cars
    Since my track car won't be available for another couple of months, when I heard that GGLC was going to get one of the first 5 mile track days at Thunderhill, I figured I'd look into renting and was told about Dietsch Werks.

    As a result, I ended up renting a track prepared lotus from them (lightened, a few extra HPs over stock, and upgraded brakes). I did however select street tires over slicks since I figured I didn't need to learn slicks when I was already learning a new car and a new track.

    I ended up flying early that morning just around IFR weather and got to Willows airport where Rob picked me up.



    By 09:00, we started our first session, one of 7 30mn sessions :)



    there were other bug cars :)
    there were other bug cars :)

    It took me a little bit to get used to the lotus and learn that it was tail happy under braking. As a result, I had to brake and be back on gas before turning for stability in some places.
    Learning thunderhill west also took a bit of time, but I worked my way down from 4:10 to 3:44 by the end of the day, so I'm happy enough with that :)

    Here is my last session of the day (just to 20:22):

    Thanks to GGLC for setting up the event and Rob and Jenni for getting me the car all prepped.

    100_20140626_Thunderhill_5mile_Elise_GGLC 101_20140626_Thunderhill_5mile_Elise_GGLC 102_20140626_Thunderhill_5mile_Elise_GGLC 103_20140626_Thunderhill_5mile_Elise_GGLC 104_20140626_Thunderhill_5mile_Elise_GGLC 105_20140626_Thunderhill_5mile_Elise_GGLC
    2014/06/23 Another Visit of Midway Aircraft Carrier in San Diego
    π 2014-06-23 00:00 in Flying
    I had spent over 3 hours in 2012 and didn't get to finish the top last time, so I went back with Arturo and we spent another 3-4H to do the top. Clearly doing the whole thing carefully takes a whole day from open to close.

    This time though we started with the top deck which usually is a 1H line and we saw right away, and then we worked through the flight deck:



    Captain's view
    Captain's view







    From there we saw the captain's quarters and surroundings, ops and comm rooms:








    From there, we went to the flight deck and dispatch rooms:









    landing signals
    landing signals














    There was a lot more to see in the aircraft carrier, but we had done a good amount for the day (and this mostly completed my prior visit where I had seen all the bottom floors in details).

    2014/06/21 Diving San Diego: Kelp, Ruby and Yukon wrecks
    π 2014-06-21 00:00 in Diving
    Arturo, Regis, and Bill invited me to their diving trip in San Diego, and having forgotten how cold it was last time, I foolishly accepted :)

    I brought a semi dry 7mm wetsuit, a full hood, and as a backup a 2nd shortie with hood that was 5.5mm (or a total of 12.5mm of neoprene). That was a wise decision, the semi-dry 7mm wasn't much warmer than a 7mm, and after my first dive, I was very cold, so I put the 2nd wetsuit on top.
    This turned out to be barely enough, and I was still cold on most of the dives, but it turns out the temperature got as low as 13C (55F). It was sad when I saw my computer say 16C (60F) and that felt warm, but the 2 wet suits, tight hood, and 28lbs of lead just weren't comfortable or fun.

    All that said, we had above average vis (which means somewhat poor instead of very poor ;) ), and no current, so we got lucky with the conditions actually being as good as they could have been for there (except the temps).

    On the first day, we did a couple of kelp dives first, and the Yukon and Ruby in the afternoon. On the second morning, double dive of the Yukon on nitrox, and finished up with the Ruby again, where I took a crap on the toilet :)

    Unfortunately most of my pictures are crap because my real camera lens kept fogging up. I used my gopro as a backup, and the nicer pictures are from Arturo.





    there we so many lobsters, it wasn't even funny:








    Some pictures from the wrecks:






    2014/06/20 A long weekend in San Diego with Arturo
    π 2014-06-20 00:00 in Trips
    Arturo invited me to join a few of his friends to go diving in San Diego, and we took some extra time to visit San Diego a bit, which I had started some years back, but didn't get to finish.

    Arturo and I took an early flight on friday morning to enjoy most of the day in San Diego:

    this is where we did our our diving trips from
    this is where we did our our diving trips from

    downtown
    downtown

    Balboa Park where Artruo and I spent quite a bit of time when we weren't diiving
    Balboa Park where Artruo and I spent quite a bit of time when we weren't diiving

    After landing we went to pick up Arturo's compact car :)


    From the airport, we went directly to Cabrillo national monument to see the beach/tide pools before the tide rose too much. It was a nice hike by the coast:










    Arturo was not much of a photo model, so I had to find other people :)



    After the coast, we went to see the Cabrillo monument and went to get some picturs from San Diego and the military base:






    how about that, it was a perfect fit :)
    how about that, it was a perfect fit :)


    On the way back down, we went to check out the cemetary on the side of road back down:



    From there, we went to the science museum in Balboa Park and went to see a couple of Imax movies:



    Next, we went to the museum of man, which closed later and wasn't bad:







    The next day, we met with Bill, Regis and Kyoko for diving, which is on its own page.

    After diving on our second day, we had a bit of extra time in the afternoon, so we went back to Balboa Park to see the botanical and Japanese gardens:












    Next, we went to San Diego Old Town, starting with Whaley House and then shops in old town:



















    The next day, Arturo and I started the day by going to the Midway Aircraft Carrier, which allowed me to see more of the top of the carrier and the command center which I hadn't been able to see last time when I concentrated on the bottom decks.

    After that, we went back to Balboa Park and went to the natural history museum:





    After it closed at 17:00, we had enough time to enjoy some yummy deserts before heading for the airport to fly home:



    2014/05/26 Visiting Japan Day 22: Zojo-ji and Tokyo Tower
    π 2014-05-26 00:00 in Japan2014, Trips

    And finally we got to our last day in Japan. Jennifer thought she would enjoy the amenities of our hotel :)


    I chose to go back to Tokyo Tower since I had gone in 1997, and figured I would see Zojo-ji, a big quiet temple just next to it, wihch happened to also be featured in X-Men's The Wolverine, much of which happens in Japan. It's a great temple, both in size and appearance:










    Next, I went to Tokyo tower, just because. It's not a first attraction (obviously, the Tokyo Skytree has stole the thunder), but if you're by Zojo-ji, why not? :)








    Odaiba
    Odaiba







    At the base of Tokyo Tower, there is a small aquarium. It's nothing to write home about, but I figured I'd check it out anyway. It actually had some interesting fish I hadn't seen before, as well as weird nosed turtles :)







    nice snapping turtle
    nice snapping turtle

    After this, I went back to our room and we walked to the Google Office for lunch with friends and a quick tour.

    And after that it was time for a bus back to Narita to fly home. A few shots from that bus:




    More pages: July 2014 June 2014 May 2014 April 2014 March 2014 February 2014 January 2014 December 2013 November 2013 October 2013 September 2013 August 2013 July 2013 June 2013 May 2013 April 2013 March 2013 February 2013 January 2013 December 2012 October 2012 September 2012 August 2012 July 2012 June 2012 May 2012 April 2012 March 2012 February 2012 January 2012 December 2011 November 2011 October 2011 September 2011 August 2011 July 2011 June 2011 May 2011 April 2011 March 2011 February 2011 January 2011 December 2010 November 2010 October 2010 September 2010 August 2010 July 2010 June 2010 May 2010 April 2010 March 2010 February 2010 January 2010 December 2009 November 2009 October 2009 September 2009 August 2009 July 2009 June 2009 May 2009 April 2009 March 2009 February 2009 January 2009 December 2008 November 2008 October 2008 September 2008 August 2008 July 2008 June 2008 May 2008 April 2008 March 2008 February 2008 January 2008 December 2007 November 2007 October 2007 September 2007 August 2007 July 2007 June 2007 May 2007 April 2007 March 2007 February 2007 January 2007 December 2006 November 2006 October 2006 September 2006 August 2006 July 2006 June 2006 May 2006 April 2006 March 2006 February 2006 January 2006 December 2005 November 2005 October 2005 September 2005 August 2005 July 2005 June 2005 May 2005 April 2005 March 2005 February 2005 January 2005 December 2004 November 2004 October 2004 September 2004 August 2004 July 2004 June 2004 May 2004 April 2004 March 2004 February 2004 January 2004 October 2003 August 2003 July 2003 May 2003 April 2003 March 2003 January 2003 November 2002 October 2002 July 2002 May 2002 April 2002 March 2002 February 2002 November 2001 October 2001 September 2001 August 2001 July 2001 June 2001 May 2001 April 2001 March 2001 February 2001 December 2000 November 2000 October 2000 September 2000 August 2000 July 2000 June 2000 April 1999 March 1999 September 1997 July 1996 September 1993 July 1991 December 1988 December 1985 January 1980