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nature abhors a vacuum

11 July 2016

full stack plane spotting and data analysis

The task at hand is simple. Whenever a particular airplane is visible overhead, send out a tweet with that notice. Don’t repeat yourself with this announcement more than twice an hour, but try not to have too much lag in reporting.

The full stack of hardware and software to do this is not particularly complicated to use once you get it all running, but there are a series of issues and observations along the way that add to the complexity. I’ll walk through the whole thing start to finish, and let you know where I left off.

The basic toolkit is dump1090-mutability for plane spotting, Node-RED for wiring flows for data processing, and Docker to package up the bits that are stable.

Plane spotting

When last I wrote, I had dump1090 running on my MacBook. Since then, I’ve taken the same software and gotten the latest dev release going on a Raspberry Pi 2.

I switched to a smaller, simpler antenna, and the result was positive: instead of having a 40 to 50 nautical mile range, now I’m in the 60 to 65 nm range (about 110 km). It might also help that the Pi 2 is not really doing very much else. That particular Pi 2 setup is using a slightly back-rev version of the Hypriot software for the Pi, so it has all of the modern conveniences plus an instance of Docker on board. The temptation was to Dockerize everything, but I haven’t gone there yet; the available Docker prebuilt releases don’t have the bleeding edge of the dump1090-mutability code, and I want to see how the whole thing runs native for a while before containerizing it.

The snag that slowed down this deployment a little was Google’s decision to enforce an API key for personal use of Google Maps. In response, the very latest dump1090-mutability pulled out its Google Maps support, and went to OpenLayers. This new support gives access to all kinds of base maps, including some aviation-specific charts. (“Not for use in navigation.”)

Another piece of this was bringing up lighttpd (“lighty”), a lightweight HTTP server that replaces the rickety built-in HTTP server that dump1090 had originally shipped with. Configuration following the supplied instructions was simple, and lighttpd looks like a very suitable system to put in place to serve HTTP on embedded-class system that need flexiblity but not a big footprint.

The other component in the Pi setup is an ADS-B feed to the excellent Planefinder site. Planefinder provides a Debian package for setting up the feed, and it runs neatly with only a minimum of overhead. As a bonus you get free use of their apps, which are notable for running in much closer to real time than others I have seen.

The Pi does not yet have a working OpenVPN configuration, so I can’t get to it over the net directly. For that I plan to revisit the SaltStack for Pi configuration I wrote up last September. In the interim, salt has been upgraded, and perhaps it will be a little more stable over bad connections; we’ll see.

Data analysis

dump1090 provides a data feed in a convenient JSON format, available through a URL on a standard configuruation. The ADS-B messages themselves are binary encoded, but the system brings them into JSON so that all of the downstream processing is very easy.

Data handling is so straightforward that you can do it all without needing any special-purpose processing nodes in IBM’s Node-RED. A standard HTTP in node polls the data at the pace that you choose, and a simple function pulls apart the record of all planes into individual records for each plane.

Getting Node-RED running is continuing to get easier over time. I’m doing prototyping work on my Macintosh again, using the new Docker for Mac setup to pick up a Node-RED container to do the work in. Kitematic comes with Docker for Mac, providing a convenient dashboard and interface to Docker Hub.

(Do note, however, that if you got Docker for Mac running a few months ago, you’ll need to go through a rebuild process to go to the latest beta. To recreate or update your containers after Beta 18 upgrade follow the provided instructions.)

Once you have both Node-RED and dump1090 running, connecting the two together is straightforward. I started with this gist from dceejay which provides the basic flow and feeds into a worldmap node that is a general programmable interface for putting things on a map. My updated dump1090 gist for Node-RED adapts the data for a slightly different format between dump1090 forks.

From here in it’s relatively clear sailing. Set up a flow downstream from the plane messages, using a filter node to match the name or ICAO hex code of the airplane that you want to track. Wire it through a delay filter to set the frequency of messages you want to allow through, and a formatting node to pretty up the message in a form suitable for Twitter output.

Incomplete image and next steps.

This is a relatively complex stack, but it all fits neatly on a Raspberry Pi 2, and with a little bit more elbow grease it should be possible to containerize everything so that it Just Works and can be made to reliably work again.

I’d like to have OpenVPN running on the Pi 2, but it isn’t yet, pending rework of Salt to get that to a current version and to port all of the work I did from an earlier version.

I’m picking up planes from 60+ nm away, but I know that with a better antenna, bandpass filter, and amplifier that I can do better. Jared Mauch’s parts list would be the place to go for starters with a very modest budget of a couple of hundred bucks.

Reception is best if you have a clear view of the sky, which suggests an outdoors installation, powering the Pi with power over ethernet.

The system is running on a Pi 2, but reports from Jared and from Phil Karn KA9Q suggest that if you do upgrade the reception that it’s possible to saturate the Pi 2. Fortunately a Pi 3 does even better at the intended task.

I’m still figuring out what the very best way to create a Docker image that handles Node-RED, especially the installation of additional nodes and the management of flows. You’d like to have the whole thing suitably tidy that it could be all loaded in from the get-go.

dump1090-mutability is still mutating! It’s under active development, both at the presentation layer and at the decoder layer. So it would be appropriate to have the attitude for at least one development machine to be sure that you were ready to rebuild from source whenever.

If you only have half of this stack running (the Node-RED side) but no access to radios, you can find an existing dump1090 installation and pull the JSON from there. This is best done only via prior arrangement and only for testing purposes or for specific tasks. It’s easy to crank up Node-RED to poll a URL every second; don’t do that to a poor little Pi.

The planes I want to watch don’t take off very often - that’s the appeal of watching for them.

2 July 2016

Plane finding with dump1090

In March 2015 I wrote briefly about plane spotting with dump1090. In short, many airplanes have ADS-B transponders which squawk out their location, airspeed, and current conditions, and you can pick up those transmissions using an inexpensive RTL-SDR tuner stick and a simple antenna.

I’ve been looking into this again to see if I can get a better understanding of how it works as well as to take advantage of a year plus of software development. Here’s a summary of the state of the art circa July 2016.

Hardware: I’m using a Nooelec NESDR Mini 2 tuner stick plugged into a MacBook Air as a portable plane-finding system. I have a Raspberry Pi 2 which looks like it could be a permanent installation for this, though the recommendation for busy skies is a Pi 3 which is enough faster to make a difference if you have a good antenna.

Antenna: The Mini 2 comes with a small whip antenna with a magnetic base, and I’m borrowing a larger antenna. There are scads of antenna designs out there for inexpensive small antennas tuned to 1090 Mhz, but I’m not there yet. There are also filters and amplifiers that can improve plane-finding capabilities; also not there yet.

Software: Here’s where I’ve made progress. The dump1090 software has been forked several times, each time with just a little bit more sophistication on the visual display as well as refinements of the decoding system. The one I’m using right now is a fork by “mutability”, available at . It’s notable for being designed to run on a Raspberry Pi, as well as a bunch of small changes in the display that make it more pleasant to use than the older software I had been using.

Range: Just like I reported back in 2015, the typical results from my house are a range of 40-50 nautical miles in every direction. I haven’t yet taken the rig to my favorite plane-spotting cafe – the Biggby at Platt and Ellsworth – which has a clear view of the southern sky at a good elevation.

Tweaking the setup: Aside from changing out the hardware and relocating the antenna, the tweakable changes seem to be adjusting the gain control on the SDR. Initial experiments don’t give me strong conclusions as to what’s best. The reviews of a $20 band pass filter are promising for increasing the range.

Feeding the data elsewhere: One of the collective efforts around looking for airplanes is the ability to share the data with commerical and non-commericial systems that aggregate data from around the world. I’m digging which has a nifty near-real-time feed of ADS-B and FAA and other international data for tracking flights. Planefinder is fast enough that I can hear an airplane overheard, check the display, and figure out which flight is there.

Satellite plane finding: The GOMX-3 satellite has an SDR with ADS-B reception and has successfully fed data to Flightradar24, another commericial plane tracking system. ADS-B receivers are expected to be installed on the Iridium system over the next couple of years, which should over time provide improved global coverage and visibility into the current status of aircraft over oceans and the poles.

What it looks like: I don’t have a permanent installation running, but if you’re interested in the airspace above San Diego, you can see Phil Karn KA9Q’s system at noting that he’s in easy range of picking traffic into LAX.

1 June 2016

Github private repositories

Github has changed their pricing strategy to allow individual accounts to have more private repositories. This is a welcome change for accounts like mine.

As part of their change, enterprise pricing has increased. I’m told that this will multiply the bills that some companies will see.

This post tests a new private repo, and links to Github pricing for future reference.

25 May 2016

Ann Arbor quiet writing escapes

Where to go in Ann Arbor to do some quiet writing, without distractions. There are plenty of cafes where there are lots of people around; this list looks for the empty places where you won’t have your attention broken quite so easily.

This is a much easier task in the summer time than it is during the school year, as the students thin out and University buildings are much quieter.

Central Campus:

  • Rackham Building reading rooms, second floor. Very lovely, very quiet, recommended by many.
  • Hatcher Graduate Library study carrels, especially on the higher floors. You’ll have a little room of your own.
  • Law Library reading room.
  • Michigan League, upper floors
  • Museum of Art
  • Palmer Commons, where the upper floors have writing desks
  • Social Work Library
  • Michigan Union first floor reading rooms


  • Ann Arbor City Hall, council chambers (not during a meeting)
  • Sweetwaters, Liberty or Washington St
  • Ann Arbor District Library, third floor (periodicals) or fourth floor (administration)
  • Zingerman’s Next Door, upstairs in one of the smaller rooms
  • Mighty Good Coffee

North side:

  • Matthaei Botanical Gardens
  • Duderstadt Center library, second floor (periodicals)

South side:

  • Ann Arbor Municipal Airport
  • Roos Roast


  • Cultivate in Depot Town

Of course, external distractions are only one part of the complex question of “why are no words appearing on the page”. There are some a few tricks that I use to minimize distractions coming from the computer itself.

  • Write in a big ‘vim’ window. Open up Terminal, maximize a window, and then fire up ‘vim’. I’m managing to get 62 lines on the screen without having to squint, and the browser is not on the screen.
  • Go offline. If your writing environment allows, do your writing without a connection to the Internet.
  • If you must stay online, mute notifications. On my Mac that’s a “Do not disturb” setting.

With a big screen up another functional way to avoid a distraction is to keep sitting until the screen is full. It’s not necessary to actually want to keep all of the words that you write - it’s OK to discard some of them in a subsequent editing session - but the self imposed constraint to fill the page all the way to the bottom on a 62 line screen produces a substantial quantity of work in a single sitting.

A useful quality to cultivate is “sitzfleisch”.

The Germans have aptly called Sitzfleisch the ability to spend endless hours at a desk doing grueling work. Sitzfleisch is considered by mathematicians to be a better guage of success than any of the attractive definitions of talent with which psychologists regale us from time to time. Gian-Carlo Rota.

Pull up a seat, open up the screen, start typing. Don’t look up until the page is full. Set yourself a time limit and a word count and aim for that. The time limit can be enforced by parking in a space where your time is limited, which reminds me that I must be going.

25 May 2016

A commonplace reader

Sometimes it’s easier and faster to fill a page by quoting from others.

The commonplace book is the annotated scrapbook, carefully collecting bits from other writers with just enough commentary and selection to make them your own. If these were written in this era you’d call it “curation”, though I can only think of that word in the context of “curated meats”, somewhat salty and dry and meant to be preserved for some time.

Anyway, the commonplace book. Why write your own words, when there are so many other good ones already written to quote from? As it is said, though no attribution is reliable,

Immature artists copy, great artists steal.

The artist steal from tonight is Brian Eno, in particular his Oblique Strategies, which I now have as three lines of shell script plus 128 lines of text. A sample, intended to be drawn at random:

Not building a wall but making a brick

As to brick-machines, this from Popular Science

Bricks are fairly easy to make, but in the developing world, traditional fired bricks are sometimes weak and crumble-prone, while cement ones are often unaffordable. The Vermeer BP714 is the first compressed-earth-block machine that makes strong air-dried bricks out of dirt. Its bricks don’t just exceed U.S. cement-code strength requirements—they’re 20 to 30 percent stronger, and cheaper than other machines’ too.

Of course that’s the story you want to tell when someone else has a lot of mud and you have a lot of machine.

The commonplace style of writing allows you to fill a page with text faster, since you’re cutting and pasting it in rather than sweating to find the exact words yourself. The downside is that you might sometimes have to hunt for the correct word, and it will be obvious that it’s someone else’s correct word. There is no question of plagiarism, just of assembly.

The serious crimes in terms of writing are that of plagiarism and copyright violation. (Reality Studio)

So long as we are going down this route, it’s worth rejecting plagiarism as a thought-crime. From Kenneth Goldsmith:

It seems an appropriate response to a new condition in writing: With an unprecedented amount of available text, our problem is not needing to write more of it; instead, we must learn to negotiate the vast quantity that exists. How I make my way through this thicket of information—how I manage it, parse it, organize and distribute it—is what distinguishes my writing from yours.

We make patchworks. Most two word phrases can be easily found on the Internet.

Most two-word phrases are not produced under unpleasant stress, but in interest or excitement. (Penelope Leach, “Babyhood”)

The important thing is to provide the reader with enough information so that the article can be easily found on the References page. (Communication Research Methods in Postmodern Culture)

Lists of real-world materials and their refractive indexes are easily found on the Internet. (Lanier, “Maya Studio Projects Texturing and Writing”)

Retroactively we can construct some level of patchwork that we can crib from, in interest or excitement.

23 May 2016

Day trips from Ann Arbor

Some suggestions for places to go for same-day destination trips from Ann Arbor. I’m collecting up ideas suitable for rides in support of driver’s ed.

East via M-14

East via I-94


  • Windsor: Via tunnel or bridge
  • Point Pelee: Bird sanctuary
  • Marine City: ferry to Canada

South via US-23

  • Carleton: Calder Dairy
  • Monroe: 1812 National Park
  • Toledo: Toledo Museum of Art (45 minutes)
  • Toledo: Toledo Mud Hens
  • Toledo: Toledo Zoo
  • Port Clinton: birdwatching

Southwest via US-12

  • Tecumseh: Michigan State Univ Hidden Lake Gardens, (one of the better kept State secrets) …beautiful trails, Hosta Garden and conifer collection.
  • Irish Hills

West vis I-94

  • Kalamazoo: Air Zoo
  • St Joseph: beaches

Northwest via US-23 and I-96

North via US-23

Thanks to members of the a2b3 mailing list for suggestions!

18 May 2016

Bots are hot - again

The title of the post is taken from a 1996 Wired article by Andrew Leonard describing the state of automated systems in the dot-com era.

Web robots – spiders, wanderers, and worms. Cancelbots, Lazarus, and Automoose. Chatterbots, softbots, userbots, taskbots, knowbots, and mailbots. MrBot and MrsBot. Warbots, clonebots, floodbots, annoybots, hackbots, and Vladbots. Gaybots, gossipbots, and gamebots. Skeleton bots, spybots, and sloth bots. Xbots and meta-bots. Eggdrop bots. Motorcycle bull dyke bots.

Bots are hot today in part because natural langauge processing has improved to the point where Google can build hardware to speed up their software algorithms and run their immense training corpuses through it quickly to fine tune their approach. The output of this effort is ASICs that speed up their Tensorflow algorithm for machine learning. Thus Google can safely give away their software, knowing that anyone else running it will use a multiple of the energy that it takes Google to do it.

It’s instructive to look at the changes throughout the years and how bots have co-evolved with the networks and computer systems that they inhabit. Early AIs like ELIZA and PARRY lived on mainframes connected to very slow wide-area networks, and it was years before the two of them talked to each other online. The 1980s and 1990s brought Usenet and the automation that could live on store-and-forward networks. AOL Instant Messenger’s ubiquitous chat met popular culture and the emergence of advertising bots like GooglyMinotaur, which promoted the music of Radiohead.

I’ve been writing what I think is some kind of manuscript about bots and their personalities, a biographical dictionary of emerging intelligences. I’m at about 10,000 words. It’s a challenge to try to corral that much quasi-intelligence onto the page, including trying as best I can to characterize some systems that are known only by people’s memories of them.

24 April 2016

Mechanical slaves and the Californian ideology

Noted elsewhere, saved here for reference, from

Richard Barbrook and Andy Cameron, THE CALIFORNIAN IDEOLOGY

If human slaves are ultimately unreliable, then mechanical ones will have to be invented. The search for the holy grail of Artificial Intelligence reveals this desire for the Golem a strong and loyal slave whose skin is the colour of the earth and whose innards are made of sand. As in Asimov’s Robot novels, the techno-utopians imagine that it is possible to obtain slave like labour from inanimate machines. Yet, although technology can store or amplify labour, it can never remove the necessity for humans to invent, build and maintain these machines in the first place. Slave labour cannot be obtained without somebody being enslaved.

Read this and then think about Siri, Cortana, “Amy Ingram” and other long-suffering inanimate machines that we imbue so much personality into that some of us unknowingly flirt with a robot because we are so charmed by their devotion.

22 April 2016

Washtenaw restaurant inspections

  • Who: Wayne Eaker and the a2civictech Slack team
  • What: Restaurant inspections from Washtenaw County
  • Where:
  • When: As they are updated, up to twice a momth
  • Why: When you eat out, you care about food safety

Some example searches:

Three restaurants with 30 or more violations

Reports from 2016 of pest problems

The hardest part of this project is that it’s dependent on an undocumented interface from the contractor who does the work for the county.

One very nice aspect of the system that Wayne put together is that you can get alerts from every time a new inspection comes out that matches your saved settings, so you can track a particular restaurant or problem over time.

22 April 2016


Yesterday’s radio was full of the Prince music catalog. The artist passed away in his Minnesota home at the age of 57. In response any radio station that had anything other that pre-programmed music responded by playing his hits - “Little Red Corvette”, “Raspberry Beret”, “Purple Rain” - and the radio stations that had artistic control also played B sides, live shows, bootlegs and whatever they could find. Ann Arbor’s own WCBN was exemplary in this regard.

The radio that I remember is from the 80s when Prince’s music was in regular play on the Electrifyin’ Mojo’s show on Detroit’s WJLB. Prince did a very rare live radio interview with Mojo, and you can hear it in two parts - part one and part two - on Youtube.

What I haven’t found yet is the computer font with a perfect Prince symbol in it. You can get close by writing the prince symbol in unicode, or this ASCII representation may suffice: O(+> . But the real deal came on a 3.5” floppy disc from Warner Bros.

17 April 2016

Earthquake in Ecuador, April 16, 2016

Ann Arbor, MI, 17 April 2016: An earthquake hit near the coast of Ecuador on the evening of 16 April 2016. As of 1:00 p.m. Eastern time the current estimate is 235 killed and 1,557 wounded from the incident. Reports are still coming in from the hardest hit areas which lost telecommunications lines in the disaster, so expect these numbers to increase.

Early reports from Ecuador came in primarily via social media, as it took a while for the nation’s news organization to cut over to flash reporting of the news from their regularly scheduled programs. The country’s vice president, Jorge Glas, provided regular and authoritative reports on damage and emergency response.

Reporting on the damage was almost entirely in Spanish, as there is no substantial English language media presence in the county. I found the automated translation service provided by Bing in the Twitter feed to be indispensible. Some words that you will see over and over again:

  • personas heridas = people injured
  • personas fallecidas = people killed
  • sin luz = without electricity
  • sismo, terremoto, temblor = earthquake

For music and (sometimes) news from Ecuador, I turned to Tunein, which relays thousands of radio stations worldwide. At various times the following channels were interesting or informative:

I looked for the shortwave broadcast of HCJB but it would appear that its English language broadcasts are no more. There is news in Spanish on the site under the Noticias banner.

Some individual news feeds to follow from the time of the event:

Thoughts go out to everyone affected by the quake.

30 March 2016

Upgrade to El Capitan

I’m working through the details of an upgrade from Mavericks to El Capitan. Some running notes.

The upgrade took about 2 hrs. I went to the Apple Store at Briarwood in Ann Arbor to get the install done, since their Internet is faster than my home UVerse.

After doing the upgrade the next big slow task is brew update. You would not be surprised to know that I have a lot of packages installed, and that brew is working hard to update everything.

The biggest reason that I upgraded was to get xhyve and thus Docker for Mac. I’m using the beta now (beta 5) and have gotten a few trivial things to work, but am still sorting out a few questions which might or might not be issues.

14 February 2016

Stadium Boulevard project bids high, portions of project to be delayed

The bids for the work came in higher than expected, so the City of Ann Arbor’s Ann Arbor Stadium Boulevard road reconstruction project will likely omit the section between Main Street and Seventh. That’s the word from the city’s engineer on the project, Michael Nearing, P.E. He writes in an email sent from his iPhone on Saturday, Feb 13, 2016 at 1:26 PM:

At this point it appears that the only realistic option to perform the project with the funds that are available is to revise the project limits. We are currently reviewing the plans, the planned work, our material choices, proposed construction methods, and the bid prices received to determine the most prudent course of action.

Once we better understand all the factors that will affect the work, we’ll share the information with Council and the public of our revised course of action.

We are hopeful the we can re-bid the project later this year and start construction after the U of M Home Football season.

Details on the city’s Stadium Boulevard Road Reconstruction Project page do not yet reflect this new reality, and the agenda for the February 16, 2016 Ann Arbor City Council meeting also does not include an agenda item on this topic.

14 February 2016

Chicken and onion curry

Saveur Magazine has a recipe for a chicken and onion curry from January 27, 2010. It took a little more than an hour to cook, but the results were very much worth it - delicious, and worth repeating.

We had the meal with rice, kale, and a daikon raita from that I kind of liked but which was not a big hit with the rest of the table.

The current meal planning regime here uses a Google calendar and a question at the end of every meal: do you want this again, and how many weeks before we have it again? This curry will repeat in 3 weeks.

25 January 2016

Ann Arbor Public Schools respond to social media threat

Ann Arbor, Michigan, January 25 2016: The Ann Arbor Public Schools issued this news release and letter to parents, signed by Superintendent Jeanice Swift.

Monday, January 25, 2016

Dear AAPS Parents,

As many of you may have already heard, there have been threats made on social media to multiple school districts across the metro area, extending to Florida, and rumored to have occurred as far as California.

Please be assured that in the Ann Arbor Public Schools, we take any and all threats very seriously and consistently follow established emergency procedures in cooperation with Ann Arbor Police Department and other law enforcement agencies.

We received information in the early morning hours that Ann Arbor was included in this social media situation. Police were notified immediately and we have been actively working with the AAPD since first learning of this issue.

Our principals were advised early this morning of this situation, and we continue to work with law enforcement officials as part of our safety protocol. We will continue to monitor this situation very closely.

As the use of social media for posting threats against schools seems to be increasing, I would like to ask all parents to talk to their children about using social media and instruct them that if they see anything on social media that is a concern, to immediately report it to an adult, such as a parent, principal or teacher. If they re-post or pass on the threat, they can also be held responsible for issuing a threat and can receive disciplinary action as a result.

Please be assured that we take every threat seriously as safety for our students and staff is our first priority.


Jeanice K. Swift, Ph.D. Superintendent of Schools


24 January 2016

M7.1 earthquake felt in Anchorage, Alaska

Ann Arbor, 6:35 a.m. Eastern, 2:35 Anchorage time: Local news coverage of the earthquake:

Ann Arbor, 6:30 a.m Eastern. A note on time zones: Anchorage is GMT-9, or 4 hours behind Ann Arbor time. The current time there is 2:30 a.m., and the quake hit at about 1:30 a.m. local time.

Ann Arbor, 6:20 a.m. Eastern: The Chugach Electric power outage map shows 3858 subscribers without power out of 28112 served mostly to the south of Anchorage.

Matanuska Electric Association is reporting via Facebook that about 4000 customers are without power due to the quake.

The earthquake at 1:30 am caused several outages including our entire Douglass substation in Willow and several other feeder outages, especially impacting the Palmer area. Crews have been called in from home to assess the situation and restore power.

Ann Arbor, 6:01 a.m. Eastern: The quake is now reported as a M7.1 - 83km E of Old Iliamna, Alaska, according to the USGS report. The did you feel it report from USGS notes that the quake was felt most strongly in Anchorage, Homer, and Kenai AK, and could also be felt by some as far away as Fairbanks AK and Whitehorse, Yukon, Canada.

Ann Arbor, MI, Sunday, January 24, 2016, 5:43 a.m. Eastern: A magnitude 6.4 earthquake was felt in Anchorage, Alaska. The quake’s epicenter was located 162mi SW of the city, according to the USGS report.

My high school classmate Mary Beth Hammerstrom alerted me to the quake on Facebook.

“Holy hell that was a big one!!!!!!!”


21 January 2016

a2b3 lunch non-summary for 3d week of January 2016

Thanks to everyone for coming to lunch. We had 16 people, and complete introductions in 23 minutes.

The topic of the question was “repair”.

  • Linda Diane Feldt is repairing her side door, original equipment on a 90 y/o house.
  • Kathryn Sanderson darns socks.
  • Dan Friedus wants to know if you want to repair his 1980s Bolens garden tractors. (Make an offer.)
  • Ruthann Nichols teaches Science and Wine as a freshman seminar at the U.
  • John Barrie recommends Fix It Friday at Maker Works, and is repairing an Advent 300 stereo.
  • Josephine (sp?) is repairing a sense of community and interviewing a new boss.
  • Lou Leone likes not having to repair things.
  • Linda Rayle is decluttering.
  • Roger Rayle says “ideas get repaired” by his efforts.
  • Larry Siden is fixing code and got a rattling guitar amp repaired in Keego Harbor.
  • Helene Gidley is also darning socks and saved some wall paper for years for a successful repair.
  • Keith Alexander is repairing blank surfaces by painting murals.
  • Kathy Griswold repaired some household lighting.
  • Kai Petainen is repairing computer models for picking stocks.
  • Tim Athan is a forensic engineer and does failure analysis.
  • Ed Weiss is looking for help to repair help files for a music synth program written in Japanese for Windows 98.
  • Ed Vielmetti has successfully repaired two shortwave radios.

Thanks to Kai Petainen for his contribution and new membership to the Meetup group. The nominal dues are $20/yr which covers the costs of hosting on Meetup. Dues are completely voluntary and we always welcome everyone who comes.

Events coming up:

  • Friday 122
  • Saturday 123 Ann Arbor Farmers Market
  • Sunday 124 Hazel Park Hamfest 8a-noon
  • Sunday 124 “Ann Arbor Cocktail Coven”, talk to Lou Leone for details, Facebook group
  • Monday 125 a2civictech w/s/g Kathy Grisworld on SeeClickFix and civic engagement, at AADL
  • Tuesday 126
  • Wednesday 127 Agile Groupies w/s/g Helene Gidley at Pillar, “Lean Coffee” format.
  • Wednesday 127 Zoning Board of Appeals; no agenda yet
  • Thursday 128 a2b3 lunch at Ayse’s
  • Thursday 128 IOT Detroit in Allen Park

Future events:

  • Fri-Sun 129-131 Makeathon at UM Stamps School
  • some future Friday: Fixit Friday at Maker Works
  • end of June: Michigan Energy Fair w/s/g John Barrie

Events in the past

  • Monday 118 Ann Arbor City Council. What do we want? DRAFT MEETING MINUTES. When do we want them? EIGHT BUSINESS DAYS.
  • Tuesday 119 a2newtech; Roger Rayle has video, I think.

Notes afterwards.

If I take notes in my notebook, it doesn’t take long to write this up.

14 January 2016

Ann Arbor area APRS network status, January 2016

APRS is the “Automatic Position Reporting Service”, a system for sharing information about the position of participating amateur radio stations. Clients transmit position reports on 144.39 Mhz; digipeaters repeat these reports to other monitoring stations; and various IGate sites monitor transmissions and send their findings to which collects worldwide data.

In recent memory there has been an APRS digipeater in Chelsea, Michigan with wide area coverage, good enough to pick up travellers on I-94 west of Ann Arbor. The Chelsea digirepeater is currently off the air, which leaves a coverage gap.

There is one station within the city of Ann Arbor. KD8TDF is in southeast Ann Arbor (EN82dg). Its coverage is enough to pick up part of I-94 right adjacent to town. A second station, AB3DC-1 is the Ann Arbor/Ypsi Rx-iGate,, right near St. Joe’s Hospital (EN82eg).

Discussion at last night’s ARROW meeting included a desire to experiment on 2 meters with digital modes. Dave New N8SBE talked about software defined radio and GNU Radio, and demonstrated monitoring car key-fobs on UHF.

APRS is a very old and useful digital mode, and I am hopeful that local network conditions will improve.

13 January 2016

January 2016 Ann Arbor Building Board of Appeals lacks a quorum

The Ann Arbor Building Board of Appeals will not meet today, January 13, 2016, for lack of a quorum.

I’d like to know the following to help understand more about this group:

  • Who is on the board, and how long have they been on it?
  • Have there been any recent changes to board membership?
  • Who is eligible to be appointed to the board, and what does that process entail?
  • What happens to decisions that the board needs to make if a quorum cannot be met?
  • What is the status of the search for a full-time building official?
  • When does the board next anticipate meeting with a quorum?
  • Who has been nominated to serve on this board?
  • Why did the board not make quorum?

The agenda for the meeting has been posted, which gives you an idea of what is not being done:

  • BBA Variance Application for 325 W Liberty
  • BBA Variance Application for 215 N Maple
  • BBA Variance Application for 121 W Kingsley
  • BBA Show Cause Hearing for 2001 Commerce
  • BBA Show Cause Hearing for 111 S Main St

The last of these, 111 S Main St, is a building on the city’s Dangerous Buildings list right on Main Street. The building has a tree growing out of the roof, spongy floors due to water infiltration, and mold everywhere according to the building inspector’s report. The unavailability of the Building Board means that the owner of 111 S Main doesn’t have to face a public hearing for another month.

8 January 2016

Ann Arbor City Council Liquor License Review Committee report, 8 January 2016

Ann Arbor City Hall, January 8, 2016 - A brief report from a jammed Council committee meeting held in the council workroom. The committee moved public comment time to the begining of the meeting to hear concerns of citizens who objected to a previous decision of the committee, memorialized as follows on Legistar as 15-1179 enacted on October 16, 2015:

Resolution to Approve a Request from Aquamarine Springs, LLC for a New Micro-Brewer, Small Wine-Maker, Small Distiller Liquor License and Dance/Entertainment Permit, to be Located at 507 S. Ashley Street Sponsors: Council Liquor License Review Committee

The committee noted that the building is located in the floodway and is also part of the Old West Side Historic District. Committee members discussed the fact that any renovation to the building would require further review by the Fire and Building Departments and may also require site plan approval. It was noted that this approval was only for the applicant to proceed with the liquor license application process.

A motion was made by Councilmember Kailasapathy, seconded by Councilmember Lumm, that the Resolution be recommended for approval to the City Council on 10/19/2015. On a voice vote, the Chair declared the motion carried.

The citizens at the meeting objected to this decision, both that they were not properly informed of the decision making at the time as well as the observation that there is a preschool nearby that should have the right to object to the decision. Several people at this meeting had gone to Lansing to register their complaints.

Also on the docket was a proposal from Glass House Brewing LLC for a “New Micro-Brewer Liquor License to be Located at 2350 W. Liberty Street”.

More later as time and space warrants.

On Arborwiki: Aquamarine Springs and Glass House Brewing, both are just the start of the articles at this point.

8 January 2016

Oxford Flood Network

The Oxford Flood Network is making a flood detection network in the UK, using low cost sensors and volunteers. They are sharing their code on Github and their results on the Flood_Network Twitter account.

They encourage you to join their effort, and no high technology is necessary. The network incorporates both readings from automated sensors (about £250) as well as manual readings from gaugeboards or photos.

New as of December 2015 is an interactive flood map. A post from Nominet describes the effort:

Nominet, in association with the Flood Network, is today launching an interactive, online map which visualises river and stream levels around Oxford. The map, showing how technology can be a part of flood defence systems anywhere, has been developed following a successful pilot project with the Oxford Flood Network. The project has been focused on exploring the potential of the Internet of Things (IoT) to create an extensive, localised, early-warning system for flood-prone areas for the first time in the UK.

The system is using TVWS (“TV white space”) as its wide area backhaul network for these sensors for hard-to-reach devices that are outside of the range of wifi. Cost-effective and reliable access to remote small sensors is one of the tough spots in Internet of Things development, it’s interesting to see TVWS as a possible solution to this issue. The other relevant technology for low-cost metro area networks for sensors is Lorawan, more about which later.

22 December 2015

How I turned 99 cents worth of kale into half a gallon of delicious ice cream

“Learn this one weird trick”

“Grocery stores hate him”

Really though it’s pretty simple. Lucky’s had a sale on kale for 99 cents, so I bought one bunch. The clerk rang it up at $2.49, and when I asked, they said it was organic. I figured I had pulled it from the wrong bin, whatever.

Get home, cook the kale (it’s delicious; recipe below). Check the twist tie to check my mistake, and find out that the kale wasn’t actually organic, and that I was overcharged.

We’ve been through the “Lucky’s overcharges” before on our neighborhood email list, where it comes up from time to time., I didn’t have to quote chapter and verse of state law, just mention the Michigan scan law. The manager hand wrote a receipt and gave me $5.00 cash as well as refunding the purchase price of the kale on my card.

Fortunately I didn’t have to buy any more kale. Chocolate ice cream was $4.99 per half gallon, and it too was delicious.

  1. Save your receipts, at least until the meal is eaten.
  2. Check the twist-ties on your produce to make sure you got what you were charged for.
  3. Organic produce PLU numbers are 5 digits starting with a 9.
  4. Lucky’s was friendly when I pointed out their error, no hassle at all.

Sauteed kale

  • 1 bunch kale (organic preferred)
  • olive oil
  • 1 clove garlic

Heat the oil until it shimmers. Slice the garlic into slices and cook until fragrant but not yet browned.

Wash the kale and trim the stems . Chop the leaves finely. Add to hot pan and stir until the kale has wilted somewhat and has changed color.

Add about 14 cup of water to the pan, then cover quickly. Steam the kale until cooked to taste.

21 December 2015

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19 December 2015

A visit to the Computer and Video Game Archive, @umcvga

Previously: University of Michigan Computer and Video Game Archive (CVGA) Fifth Anniversary

I had a chance to spend some time at the U of Michigan Computer and Video Game Archive tonight, with J in tow (or perhaps I was in tow). We played for about two hours in total, and then adjourned for dinner to talk about new and classic gaming and game emulation. He snuck in a few games of Tetris on his phone afterwards.

Here’s a few game reviews and observations.

The first game I turn to at the UMCVGA is an arcade version of Centipede. The archive has an Arcade Legends cabinet that has real arcade controls, and then emulated games running on some kind of Linux system running MAME inside. “Legendary arcade games authentic in every detail” says the pitch, and the game comes with the crucial trackball that makes the arcade version of Centipede a singular experience.

As an Atari game, Centipede is also available on other systems, and I looked at it on the Atari 2600, running on original hardware including a vintage analog television set for the display. Centipede is not very complex, and the 2600 version is faithful to the original gameplay for the most part. The graphics are as flickery as I had ever remembered, especially when you hit your target.

A reasonable life goal is to play Centipede on as many systems as the Archive supports. The Mirlyn catalog currently suggests that there are eight versions of Centipede available, on platforms including Sega Dreamcast, the TI-99, Atari 2600, Sega Genesis, Playstation Portable (PSP), Windows 95 / 98, Playstation, and Windows XP.

Animal Crossing on the Nintendo 3DS was new to me, though I had heard Brian Kerr talk about it for quite some time. Animal Crossing is really fun in a quirky little way that a social casual game that’s age-appropriate for seven year olds can be. I didn’t get very far into the game, but it was clear that every character in the game that interacted with me was super happy to see me back in the system, and that kind of welcoming reunion greeting was something I want to emulate myself.

A recent (January 2015) interview with David Carter (superman) on PRX was a good 17 minute listen about the current state of the archive.

On PRX: Six Years Inside the Computer & Video Game Archive with David Carter from Radio Free Culture:

David Carter of the Computer & Video Game Archive at University of Michigan tells us about the collection, how it’s used in an academic setting, and a little about the care and feeding of elderly video game consoles.

I have a next visit already scheduled for January.

17 December 2015

Santa visiting Swede's Diner, Ann Arbor, December 1950

Santa visiting Swede’s Diner, Ann Arbor, December 1950. From the Ann Arbor District Library “Old News” collection.

Original caption: Stockings wouldn’t hold the Christmas cheer served up by Leonard Carlstrom, proprietor of a lunch counter at 208 S. Fifth Ave., so he used cups. Carlstrom played his own version of Santa Clause this morning when he hung up the “free coffee” sign to old customers and newcomers alike. “Business kind of picked up a little,” Carlstrom noted.

Notes afterwards

Recreating more or less my original layout, but with dynamically loaded content. I guess that could work!

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