How Air Conditioning Works

On the occasion three years ago of the 110th anniversary of the recognized invention of the modern form of air conditioning, I wrote this little historical/modern explainer about how heat-exchange and air-conditioning systems work for the Economist. Yes, the terrible title, "It's the Humidity," is all mine.

But I was trying to explain to Rex, age 8, this morning how air conditioning worked. I tried a bunch of explanations and metaphors, but this one stuck.

Imagine you have a pool that's 90°F. There is an endless line of swimmers who have a natural resting temperature of 60°F waiting to jump in. Each time one jumps in, they warm up to the pool temperature, and the pool, by necessity, gives up some of its energy to each swimmer, becoming cooler. The swimmer is then shot out through a chute, the friction of which warms them up even more. They stand in front of fan that cools them back to 60°F. Then they get back in the pool.

This is more or less it. A heat-exchange system has a coolant that has a low boiling point, so it's easy to manipulate it to absorb heat and shift from a liquid to a gas and vice versa, as well as varying pressure in gaseous and liquid states. The idea is that a fan takes in hot air, runs it across coils that absorb the heat, cooling the air, while circulating the heated coolant to an outside radiator or with a fan that helps vent the heat outside.

As with most things related to temperature change, it's a funny thing. Is "cold air" something real or is it reducing the temperature of air in its vicinity?

 

Over the Air, PVR, with a Rube Goldberg on Top

I can watch live and recorded TV on my Apple TV! It's very simple.

I installed an Ethernet-connected TV tuner from SiliconDust called HDHomeRun. It's plugged into a digital TV antenna on our roof. Then I use Elgato's eyeTV software on a Mac on the network to schedule and record over-the-air (OTA) programming.

That Mac is downstairs; our TV is upstairs. When I want to watch TV, I just:

The bizarre thing is this whole sequence works.

Giant towers broadcast digital signals that we capture a time slice of and convert into another digital format which are stored on a drive and then streamed over a Wi-Fi network to a mobile device that pushes it over Wi-Fi to tiny box that's connected to an HDTV.

It's as easy as 1, 2, 3…4, 5, 6, 7…8, 9, uh, 10, 11.

Everything Is Mildly Broken, Part X of Many

Working on my new Mac mini, everything froze. Moments passed. The mouse resumed action. The screen went black. Then a login screen appeared. At least it didn't fully crash, but it took a good 20 minutes before all the apps had recovered—longer than a reboot for whatever internal reason.

I'm working on my iPhone and the screen goes blank and then the Apple logo appears. The springboard crashed. This happens every couple of days.

My Apple Watch won't show apps that appear as installed via the Watch app. I installed 1.0.1. A bunch of icon previews (the outlines) show up on the Watch. Time passes. Everything rights itself.

In the morning, I pick up my watch and try to unlock it via my phone. It doesn't work. I tap in the Watch unlock code on its face, and it's lost the connection with the phone. Again. Even though the phone is right there

This isn't how it was supposed to be. It isn't how it was.

Comcasterrific: Bills, Plans, and Caps

A few months ago, I noticed that Comcast had raised its $5/month modem rental fee to $13/month. Normally, I don't rent hardware of any kind, but when I started with this one, it was at least a couple hundred dollars, and cheaper to rent. Plus, Comcast guaranteed it would work. So I called Comcast to find out what modems were compatible, bought one for $80 and had someone there activate it for me and remove the rental charge. My wife returned the modem for me and got a receipt.

And then the charge appeared the next month and the one after. Comcast doesn't do email-based support, and their phone tree is terrible. I am disconnected after choosing options more times than not. Maybe 90% of the time I call. So I complain on Twitter, where they're responsive. Someone apologized, took the charges off, and credited me $20. Fine.

I just checked my bill in the process of looking at speed options. I'm tired of getting 3 Mbps upstream as I do now, as I have a lot of data to ship to the cloud. 3 Mbps is absurd in a developed country. Other lands have 20 Mbps or 100 Mbps symmetrical at rates lower than I pay for 16/3 Mbps, even when the overall cost of living is substantially higher.

And Comcast had charged me a rental again. I also found that I'm paying $60/month, but my account said for $62/month I should be getting 25/5.

I again went to Twitter, and someone there took care of the charge. I'll have to check again next month because Comcast. (Comcast's brand promise: Our bill is never right and there's no consequence of any kind for us being wrong.)

I have "business-class" Comcast, because I moved an office a few years ago, and Comcast has a 75% cancellation penalties on unused parts of a contract. This should probably be illegal, and if challenged, maybe it would be thrown out. But at the time, Comcast had a 300GB/month usage limited, and I'd exceeded it in testing backup services.

I was able to bring the business service home, and only pay about $10/month more. It was a good tradeoff for having no cap on usage. When I did the transition, I routinely saw 15 to 25 Mbps downstream and 5 to 15 up. Now they are much more careful at shaping traffic, even though their overall capacity can mostly allow much higher usage during non-peak hours.

The customer rep I was talking with on Twitter noted I could switch to residential service and get much higher speeds for the same money. I said, yes, but you're testing overage fees in some markets, and I don't have those now. The person agreed if I were concerned about that, I had the best service for now.

Meanwhile, in Kansas City, Missouri, where Google Fiber has one of its few operations, 1 Gbps up and down—symmetrical service—is $70 per month, no limits. Elsewhere in Seattle, where our telco is lightly building out gigabit service, it's $80 with a bundle and has no caps. In my neighborhood, they promise "up to" 40 Mbps downstream DSL for $30/month, but other neighbors report getting below 10 Mbps.

Comcast said before the FCC announced its regulatory change for Internet service earlier this year that such a change would affect its investment plans. Then a few weeks later (before its merger with Time-Warner Cable was called off days ago), Comcast said it will push 2 Gbps service to be available to 18 million households by the end of 2015 and 1 Gbps to almost all its service territory by the end of 2016.

I'll soon be paying less, getting more, or both. But all of this just demonstrates the necessity of competition, the broken nature of Internet service in America, and why other countries got it right before we did.

For now, I think I'll find a gigabit café to upload my photos.

iWatch, iHub

I had a vision this morning of where the Apple Watch fits into the bigger universe of things. As I said at the launch, this first version is not what Apple intends to make at all. It will have a highly interested but likely limited audience, and it will make huge margins on the top end of the basic watches plus the premium ones, like gold.

The ultimate form of the Watch comes when it can contain all the sensors and radios of a current iPhone. That's probably within two years — Watch 3. Most of the improvements in battery performance in an iPhone go to power bigger and denser and brighter screens. In a Watch, the power needs for a cellular radio (multiple standards), Wi-Fi, GPS, and MEMS (accelerometer, gyroscope, etc.) will likely be low enough by then and the chips advanced enough to work.

In that view, the Watch stops being an adjunct to a phone, but the pivot point around which the Apple universe turns, which you can see in its use as enabling Apple Pay for some phone models. The Watch becomes:

  • The key to your house, that turns off your alarm.
  • The tracker of your health, which is already planned in the first release.
  • The way you pay, but no longer with a phone.
  • The thing you have and thing you are (biometric) for two-step or two-factor authentication.
  • The entertainment hub for your car, which no longer needs a radio/receiver unit at all, but just a surface-mounted magnetic charging dock against which you place your Watch while driving.
  • What you use to stream and remotely control audio and video to your AirPlay devices.
  • How you unlock your Mac or phone.

HomeKit, HealthKit, Apple Pay, AirPlay, CarPlay, Touch ID, iCloud. The Watch is the digital hub around which everything rotates in the new Apple universe.

A phone, a tablet, a car screen, an HDTV, a monitor, a Mac display — these all become the extensions of the same digital identity that the Watch facilitates managing. You may no longer need a phone, but the focus shift from a phone to the Watch as your pivot point. That's the transition Apple expects to make.

Apple Updates To Fix Some Annoyances

Apple released OS X and iOS updates today with a little more verbosity than they have in recent years. Yosemite 10.10.2 includes a Wi-Fi disconnection fix, and we'll see if that finally nails a bug that dates back to beta testing and has driven some people bananas. I've seen it in roaming problems in my house, in which Yosemite won't hand off from one base station to another, despite a poor signal. Several other items in the list appeared in my or the mega-comments for The Software and Services Apple Needs to Fix.

The iOS 8.1.3 fix repairs several issues, including the bug I've seen repeatedly in which apps are not searchable via Spotlight—they don't show up in results. This is a four-month-long bug for a feature I and others may use multiple times a day. (It didn't always fail, but it did at least once a day for me.)

Isles of Stability and the Perception of Apple's Software Getting Worse

On the most recent episode of the Accidental Tech Podcast (#99), the fine hosts discussed a number of things related to whether Apple's operating systems have become less stable or well executed. They made a few points that I think emphasize the sensation that things are worse, even if one could argue that this is part of a routine cycle.

Isles of stability. New OS releases always have teething pains, and if we're lucky, a rocky 10.x.0 is fully stable and good by 10.x.2 within about two to three months. (Dirty secret of all software: when version x.0 ships, they're already working on x.1, because they ship with known problems, but the damned thing has to get out the door. ) However, when OS releases were more than a year apart, we might have a few months of pain, during which period we would either delay or deal with the problems, and then exit what John Siracusa called the regions of pain. We would have sometimes a year or much longer in an island of stability. Marco Arment said, "Now it seems like we're always using a 1.0 or a 1.1…because the updates are moving so quickly."

Joran Elias compiled this chart of major and minor releases. The X axis is time; the Y axis breaks the operating system versions apart. The dots represent each minor release for a given cat/California place. The critical number are the number of days between major releases. If you pair Leopard/Snow Leopard and Lion/Mountain Lion together, you can see how little time Mavericks had.

Cloud dependencies. Because so much of iOS and OS X has a cloud component, any failure in syncing or availability makes little problems seem far worse, and provides an overall sense of gloom that may not be backed up by the actual experience and uptime. John recounted his wife having an iCloud Contacts syncing problem which I did as well: without any notification of failure, syncing stopped, and it required mucking about to restart it, instead of it auto-healing (or even warning me or his wife).

They should do better by now. Even if, as John argues, Apple is no worse at software now than in the past, at this point of maturity and sophistication, it's simply unacceptable to be as good as they were in the past. (This says nothing of breaking features that work.) Apple can and should be held to higher standards of software development quality than a decade ago. And many of its problems can be tracked in some measure to quality assurance (QA), which involves rigorous testing of changes or additions to make sure nothing breaks. Either QA remains weak at Apple, which is bad because developers shouldn't be relied upon to test all the iterations of their own work against real-world scenarios; or QA teams aren't provided the tools to send work back to developers to be fully fixed.

Together, these provide the feeling of things being worse, even if they aren't. I'd argue that the sheer quantity of stuff that doesn't work the way it should is huge, and has gotten worse, but the sensation is probably what drove me and others to write about it. In the past, we expected stuff would eventually get fixed; now, it just feels like things are broken all the time, and don't improve.

The Software and Services Apple Needs to Fix

Marco Arment's excellent post on Apple's current state of development has this pithy sentence:

…the software quality has fallen so much in the last few years that I’m deeply concerned for its future.

Apple has huge cash reserves, is massively profitable, and none of that seems likely to falter, nor is that by any means what Marco meant. None of us think Apple will go out of business. Rather, that we will lose the reasons we have selected using Apple's products over those of other companies.

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My Revised Ebook on Setting up Apple's Wi-Fi Routers

For a decade (!!), I've been writing and revising a book on using Apple's Wi-Fi routers. Long ago it was Take Control of Your 802.11b AirPort Network, and the current, fifth edition has the moniker Take Control of Your Apple Wi-Fi Network. This latest update (a bit late and all my fault for that) brings the title up to date for 802.11ac, the newest and fastest flavor of Wi-Fi, as well as OS X Mavericks, iOS 7, and Windows 8.1.

The book's designed for any home or small-business user who finds that the basic information Apple provides isn't enough. While I fully agree configuration has never been better for Apple's AirPort Extreme, AirPort Express, and Time Capsule base stations, if you want to configure network layouts or network details outside of quite standard arrangements, you might feel at sea. This book is designed to help.

I go through how to set up basic networks and more advanced ones, including creates pods of Ethernet-connected or Wi-Fi–linked base stations (and mixed groups), as well as walking through all the networking settings and how to use them for specific tasks. I fully explain the ins and outs of AirPort Utility both for OS X and the similar, but more limited iOS version. And I tell you how you can make the Eye of Sauron appear on your Mac.

For instance, you can choose a static, unchanging local address for any computer or device on your network through DHCP Reservations. It's several steps with a few choices, and I take you through that. The book also explains frequency channels and the various Wi-Fi/802.11 standards, and how to site your equipment ideally and troubleshoot it when it doesn't work.

For more details on the book—which is available in DRM-free PDF, EPUB, and MOBI that you can use anywhere without restriction—and a downloadable excerpt, visit the Take Control page. At $20, it could save you an amount of frustration you can't stick a price tag on.