Hiking with Ruby

Today Emily and I hiked 7.7 miles with Ruby at Purisima Creek Redwoods Open Space Preserve. From Skyline Blvd at an elevation of 2,000ft down to Purisima Creek Rd at an elevation of 430ft, and back. You can see info about the hike on Strava. The “Flyby” viewer is cool—you can press the play button and see a replay.

Purisima Creek Redwoods OSP is in the Santa Cruz Mountains between San Mateo and the Pacific Ocean. There are redwood trees, creeks, ferns, lots of valleys, and a few views of the ocean. The trails we took were mostly shaded. It’s a nice place, though the trails do have quite a bit of elevation change.

This was the third hike we’ve done with Ruby. The other two were shorter, at Water Dog Lake Park in Belmont (hike 1, hike 2). Ruby can’t walk yet (come on, Ruby! get with the program!) so I’ve been carrying her on my chest in a Babybjörn. She weighs around 12 pounds and the Babybjörn adds another pound or two. We look like this:

Me and Ruby hiking

She seems pretty happy in there. It’s snug and padded and warm next to my chest. She mostly either sleeps or looks at all the green. We cover her head and arms with a blanket when we’re in the sun.

Today we both wore hiking packs and CamelBaks. I carried our three legged camping stools and we stopped twice to feed Ruby and eat. We did one diaper change… we probably should have done two. With our food water, stools, and baby supplies my pack was around 20 pounds and Emily’s was 10 or 15.

Toro didn’t join us today. Although he does enjoy spending time outdoors with us, the length and steepness of this hike would have been hard for him.

We had a good time and got a great workout.

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Great albums, volume 3

One cool thing about scrobbling all music played from my home and work computers is that I have a pretty good record of what music I’ve listened to the most. Here’s a list of some albums that I think are fantastic (continuing a trend from 2005 and 2008).

Adele, 19
Bill Withers, Greatest Hits
Céu, Vagarosa
Florence + the Machine, Lungs
Foster the People, Torches
Madonna, The Immaculate Collection
No Doubt, Tragic Kingdom
Paolo Nutini, These Streets
Ra Ra Riot, The Rhumb Line
Rodrigo y Gabriela, 11:11
The xx, xx

Also I think it’s funny to see a picture of Bach in here:
screenshot of Last.fm top artists

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Blue Apron

I’ve been doing a lot of cooking this week while Emily cares for our new daughter. Blue Apron meals, mostly. Seven of them (we got a little behind while in the hospital).

Blue Apron is a service that once a week sends you a box of ingredients and recipes for three different meals. I find that it takes around two hours on average to chop, cook, put dishes in the dishwasher, and clean the kitchen. Way more time than I’d choose to spend preparing food, but if this is appealing to you then you should totally try it. They do a good job. The food is usually pretty good and it’s an effective way to learn about new ingredients and cooking techniques.

I’ve done more cooking over the past week than at any other point in my life. I blanched things. Used an oven on more than one occasion. Ate goat cheese a few times. Bedlam.

Shiitake Mushroom & Cabbage Dumplings

Spicy Orange Chicken Wings

Broccolini & Goat Cheese Polenta

Fresh Beet Linguine

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Dear Government: Please Don’t Muck With Encryption

I was prompted to write this after hearing that the Obama Administration is meeting with the creators of a petition for strong encryption (edit: you can now read the EFF’s thoughts).

Over the past year officials of various governments have expressed a desire to limit encryption or require backdoors to allow government spying (FBI director James Comey, UK Prime Minister David Cameron, US President Barack Obama). This is misguided.

The road to hell is paved with good intentions.

Encrypted communication is hard enough as it is

Considering the number of severe vulnerabilities in SSL/TLS discovered over the past five years I’m surprised https is even still useful. Building encrypted communication software is difficult. Requiring it to be intentionally weakened in specific ways will lead to an increase in unintentional bugs and less secure software.

(This paragraph added eight hours after initial posting:) There’s an underlying question of how feasible it is to add a backdoor to a given encrypted system. When looking at low level encryption protocols it’s potentially impossible. For example, trying to add a backdoor to PGP would fundamentally change PGP. It would no longer be PGP. For a higher level encryption system where encrypted messages transit through an intermediary, perhaps the system could be changed so that messages transit through a government-controlled system, and perhaps the protocol could be changed such that the intermediary decrypts then re-encrypts the message. While these types of changes are feasible, they add complexity to the system. Complexity reduces reliability of the system as a whole and increases the cost of maintenance and initial development.

You can’t stop criminals from using encryption without backdoors

Encryption software without backdoors already exists. Requiring backdoors in a few countries won’t cause this software to stop existing. It won’t prevent cryptographers and software developers in other countries from developing stronger encryption products. Criminals in the US will continue to be able to use strong encryption software regardless of any law preventing it. Making strong encryption illegal reduces the security for those of us with good intentions while acting as only a weak deterrent for those with bad intentions.

Backdoors would be used inappropriately

Regardless of whatever strict requirements are placed upon usage of backdoors, they will be abused. Maybe a hacker will break into a government computer and steal a secret decryption key. Maybe a disgruntled government worker will spy on his boss. The exact scenario is immaterial. Time is infinite, abuse is inevitable.

Therefore it’s not helpful to have a conversation about whether a backdoor will or will not be abused. It is only helpful make the best prediction about how much abuse will happen and decide if this amount is tolerable.

Massive data breaches happen quite frequently. I’ll concede that US intelligence agencies have a decent track record so far (though the Chelsea Manning and Edward Snowden leaks are two titanic counterexamples). I’m not optimistic.

Privacy is a requirement for free speech

The Guardian article mentioned above sums it up well, “the right to privacy runs right in parallel to our right for free expression. If you can’t say something to a friend or family member without the fear the government, your neighbour or your boss will overhear, your free expression is deeply curtailed.”

This argument pertains less to backdoors, where presumably a warrant would be required, and more to banning encryption outright, as David Cameron desired.

Encryption for everyone

Encryption, by the way, is pretty important. Without https and without encrypted Wi-Fi anyone within a few hundred feet of your laptop would be able to see everything you’re doing. Every website you open. The contents of every email you send. How much money is in your bank account. People could capture your login credentials and wire transfer all your money to their own account. Trade stock in your brokerage account. Turn off automatic bill pay for your electricity or mortgage. Buy things with your Amazon account.

Personally I place a high value on my privacy and a low value on the potential of intercepting terrorist communication via a backdoor. The dubious benefits of backdoors do not justify the costs.

Tangentially related blog posts from me:
Violating the Fourth Amendment
Should the NSA be allowed to scan our personal email?

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17 years and 100,000 miles with an Acura Integra

I’ve had the same car for 17 years. It’s a “Vogue Silver Metallic” 1998 Acura Integra LS, 2 door automatic, and a week ago it crossed the 100,000 mile mark.

17 years and 100,000 miles

Overall

I’ve been happy with it. It’s solid, well-made, and has had few problems. Although Acura is Honda’s luxury brand, this car is basic. Not sure what I mean? Here’s an incomplete list of features this car lacks:

  • Automatic on/off for headlights and parking lights
  • Keyless entry (I think it was optional. I added an aftermarket system)
  • Adjustable rate for the intermittent windshield wiper speed
  • Electric seat adjustments (was possibly optional… I don’t remember)
  • No interior dome light
  • Steering wheel stereo controls
  • Outside temperature display
  • Variable valve timing (whether for increased fuel efficiency or increased performance)

Granted it is from ’98 and we’ve come a long way since then.

I still like it. It’s comfortable for me. It’s pretty low to the ground so visibility over other cars isn’t great, but I’m ok with that. The cost of ownership has been fairly low. No chronic problems or mechanical disasters. I get 29 mpg with pure highway driving. Maybe around 25 mpg for city driving.

Biggest problems

Poor automatic transmission

Shifts are rough and slow. The car loses power a bit then mildly lurches forward when moving up through gears while accelerating. It’s been like this as long as I can remember. I don’t know if this is specific to my car or to all Integras. You can partially mitigate the jerkiness by increasingly lifting your foot off the gas pedal as you approach the point where the transmission shifts, then pressing the pedal in as the shift finishes. I think I do this unconsciously now.

Trunk latch

This is a common problem on third generation Integra hatchbacks. There’s a small lever attached to the hatch. You slide it sideways to trigger a solenoid on the car body that releases the lock, then lift to open. Mine stopped working maybe in 2004. Now I must insert the key and turn clockwise with one hand and lift with the other.

A search for “integra trunk actuator” turns up lots of results (a few: hatch lock stuck, G3 Rear Hatch Opening Problem 98+, hatch opener not working, How to Fix an Acura Integra Hatch Actuator, Fixed My Broken Trunk Latch). Some people suggest replacing part 74840-ST7-A01. I tried it but it didn’t fix the problem for me. I think I might have an additional problem where power isn’t reaching my trunk. Possibly due to a blown fuse.

Assorted smaller problems

  • Rear window washer fluid sprayer stopped working years ago.
  • Trunk light doesn’t work (and was fairly ineffective when it did).
  • Radiator cracked and needed to be replaced maybe around 60,000 miles.
  • Antenna stopped going up and down around 96,000 miles.
  • The rubber bits on the outside are deteriorating. Gaskets around the sunroof, windows, between body panels, etc.
  • The paint on the top of the arms that hold the side mirrors has gotten bubbly and chipped off.
  • The engine is fairly weak—basic 1.8 liter Honda inline 4. Either 137 hp or 140 hp, depending on who you ask.
  • The suspension is basic—the ride has certainly never been posh.
  • The heater is slower and doesn’t get as hot as Emily’s 2003 Toyota Corolla. The air conditioning is usually good enough, but is certainly not overpowering.
  • After having disassembled and reassembled various pieces of the interior over the years to replace the stereo or speakers, I’ve noticed that the paneling tends to be made of a harder, more brittle plastic than Emily’s 2003 Toyota Corolla. The plastic feels more likely to break when pried. Whereas the Corolla plastic feels more rubbery and resilient.
  • Not a lot of sound dampening. Ambient road noise tends to be louder than most newer cars.
  • Update 2015-10-14: The little green circle around the “D4” indicator in the instrument cluster stopped working around 100,600 miles.
  • Update 2016-1: The green indicator light on the cruise control master on/off switch stopped working around 101,000 miles.
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Quotes, expressions, and mantras

Here’s a collection of quotes, expressions, and mantras that I appreciate. They’re things I respect. Or agree with. Or would make me a better person if I followed more closely.

We need to be the change we wish to see in the world.
Not actually Mahatma Gandhi

The softest pillow is a clear conscience.
–N. R. Narayana Murthy, also maybe Tejomayananda, also maybe an old French or Russian proverb.

A society grows great when old men plant trees whose shade they know they shall never sit in.
–Greek proverb

The best minds of my generation are thinking about how to make people click ads. That sucks.
–Jeff Hammerbacher, “This Tech Bubble Is Different”

In anything at all, perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away, when a body has been stripped down to its nakedness.
–Antoine de Saint-Exupery

We who cut mere stones must always be envisioning cathedrals.
–Quarry worker’s creed

To command the wheel of an open car with a girl on the seat beside you was to be established in a condition that only a fool would hasten to end.
–Tobias Wolff, The Night In Question

It is the way of spiritual growth
A man must go forward from where he stands
He can not jump to the absolute
–Bela Fleck and the Flecktones, Sojourn of Arjuna

You could be better than you are.
–Bing Crosby, “Would You Like to Swing on a Star”

Choose your battles.
–no one in particular

Work hard, play hard.
–no one in particular

If you’re not being productive, stop what you’re doing and do something else. If you’re being productive, keep doing what you’re doing.
–me

When making a decision, avoid regrets. If you think you’ll regret something then don’t do it. If you think you’ll regret not doing something, then do it.
–me

Don’t half-ass it. Don’t cut corners.
–me

Don’t put your tools away until you’re done with the job. Also: Always put your tools away when you’re done with the job.
–me

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The Golden Records

In 1977 NASA launched the Voyager 1 and Voyager 2 space probes to study the outer solar system. Voyager 1 flew by Jupiter, Saturn, and Saturn’s largest moon, Titan. Voyager 2 flew by Jupiter, Saturn, Uranus, and Neptune. After 37 years the probes continue to send data back to Earth as they hurtle out of the solar system.

Each probe contains a gold-plated copper record encoded with images and audio from our planet. It’s fascinating to see the list of sounds that people thought were important enough to use as an interplanetary greeting. It’s like a greatest hits album for our entire planet: birds, the ocean, Chuck Berry, Mozart, a tractor.

The easiest way to listen is probably YouTube. There’s also goldenrecord.org and another option, but I find the YouTube playlist navigation to be easier. There are also official NASA playlists on SoundCloud, but they only include Greetings to the Universe and Sounds of Earth.

More information here and here.

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Let’s learn about furnaces!

When we moved in to our new place our furnace wasn’t quite working. We didn’t notice it at first. It would turn on for a few minutes and sounded normal, but then it would turn off before reaching the temperature set on the thermostat. This is known as “short-cycling.”

Our furnace

Our furnace is a Gibson GL1RA 045N-08A. It’s a basic single-stage, non-condensing, natural gas, forced air furnace. The control board dictates the run sequence, which is something like this:

  1. Thermostat indicates that the heater should run.
  2. Draft inducer blower begins running to move air past the burners, through the heat exchanger, and out the exhaust flue.
  3. 30 seconds later the hot surface ignitor starts.
  4. 30 seconds to a minute later the gas valve opens and the burners ignite. The hot surface ignitor is depowered. Exhaust gases flow through the heat exchanger and out the exhaust pipe. The “burners,” by the way, are just pieces of metal that guide the gas and flame into the heat exchanger
  5. A short time later the main furnace blower turns on and begins moving air past the heat exchanger and into the house.

Due to the inherent danger of fire and explosive gas, modern furnaces include many safety sensors. If something is amiss the furnace errs on the side of caution and shuts itself off.

If the draft inducer blower isn’t able to move enough air (maybe a bird built a nest in the exhaust flue), a pressure switch detects this and shuts the furnace off. Because if hot gasses can’t exhaust properly the furnace could overheat. Or carbon monoxide could flow into the house.

The flame in a furnace is designed to follow a defined path: through the burner and straight into the heat exchanger. Flame rollout switches detect if a flame exists outside of this defined path and shut the furnace off.

Our issue #1: Flame sensor

The flame sensor is another important safety feature. As you can probably guess, it detects the presence of a flame. If there is no flame then the gas will be turned off within a few seconds.

Furnace flame sensor
This is what it looks like! Please excuse my scaly climber hand.

The flame sensor is nothing more than a small metal rod. It mounts through a sheet of metal via an insulating ceramic bracket. The non-flame end of the sensor connects to the furnace circuit board.

It’s pretty insane how flame sensors work. From what I’ve been able to learn, it sounds like the control board applies an AC current to the flame sensor and electrons flow from the sensor through the flame to ground at the base of the flame, thus creating a measurable current. It’s called “flame rectification,” if you want to read more about it. The current is only milliamps but it’s enough to be detectable.

To work correctly the flame sensor must be clean. Apparently these things can accumulate enough residue over time that they become unable to reliably conduct the small current from the flame. That wasn’t our problem. Sometimes the heat from the furnace can cause the ceramic mounting bracket to crack thus causing the flame sensor to touch ground and short circuit, which makes it unable to detect the flame. Our flame sensor was grounding out, but this wasn’t the reason.

No, our problem was more unique. Each port in the heat exchanger contains a metal rod called a “baffle” that is apparently supposed to improve heat dissipation. One of the baffles was sticking out of the heat exchanger and pushing against the flame sensor. I have no idea how something like this happens. The baffle was not being held in place by the metal retaining wire. Probably a careless error during a routine servicing.

Furnace heat exchanger baffles
The baffle in the middle is great—it’s not sticking out and the retaining clip is holding it in place properly. The baffle on the left is bad—it’s sticking out and the retaining clip isn’t doing a damn thing. The flame sensor would normally hang down just in front of the left baffle.

Our issue #2: Over-temperature limit switch

And the final as yet unmentioned safety sensor is the over-temperature limit switch. Furnaces are built to withstand specific maximum temperatures. The over-temperature limit switch is suspended in the air around the heat exchanger. If this air becomes too hot it might shorten the lifespan of the furnace. There are a number of possible causes:

  • Lack of airflow. Maybe the air filters are dirty or the homeowner closed all their vents or the blower motor is dead or dying.
  • Gas flow is too great. This is referred to as “over-firing.” It causes too much heat to be created.
  • A hole in the heat exchanger. This is bad as it means carbon monoxide is being expelled into the house.
  • And one final possibility: The temperature sensor is bad. This was the case for us. Replacing was fairly easy… just had to disassemble and reassemble a few chunks.

Cost to fix?

$160 for an HVAC guy to not quite fix the flame sensor problem, $30ish for a replacement flame sensor that I didn’t need, $20 for the replacement temperature switch, $6 for a roll of gas pipe teflon tape, and the biggest cost of all: About 50 hours of my time researching how furnaces work, watching many many YouTube videos about furnaces, finding and visiting a furnace parts store in SF, calling the HVAC guy, meeting him and discussing the problem, and of course writing this blog post.

Update:
After the above changes the furnace ran for longer, maybe 15 or 20 minutes, but was still short-cycling. I bought a digital manometer and static pressure probes. I measured external static pressure (aka the pressure difference across the furnace) and determined that it was higher than ideal, but reasonable. I measured gas pressure coming out of the gas valve and discovered that it was about 0.6″ WC high. I adjusted it to 3.5″ WC, as specified, and that allowed the furnace to run a few minutes longer, but it still short-cycled. I bought a digital thermometer with temperature probes and confirmed that the temperature near the temperature sensor really was at the high end allowed by the over-temperature limit switch. I made two final changes:

  1. Increased the speed of the blower motor by changing the cables plugged into the logic board such that the higher blower speed (typically used when the A/C is running) is used when the heat is running.
  2. Removed the baffle rods. I couldn’t find any reference to them in the Gibson literature or part lists. Maybe they were added by a misguided furnace installer or during a maintenance visit? They seem to cause too much heat to collect in the bottom part of the heat exchanger, rather than spreading evenly.

I changed the blower speed before removing the baffles. Now that the baffles are gone it’s possible I could reduce the blower speed without trigger short-cycling—I haven’t tried.

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