Apr 14

Basic Electronics Skills: Soldering

Who is interested in learning some basic electronics and soldering skills? I will arrange a hands-on “maker” experience where we will build some small, cool little electronic thing that you will be able to take home with you afterwards. The cost will be in the $50 range, and is for materials only, all of which will be yours to keep.

The first thing you need is a decent set of tools.  I can provide some tools during class, but if you want to solder on your own, or don’t want to wait and share during class, you should buy one of these, or something like it.  Whatever you buy, it should have a 20-25 Watt soldering iron, some solder, a wire cutter and pliers. A solder remover and/or solder wick is a very good idea.  You can buy the tools seperately, or in kits like below, which are all less than $50, most less than $25.  I have lots of pliers and cutters, so the soldering tools are the most important part:

  1. Maker Shed soldering kit (has pliers)
  2. Think Geek Kit (has pliers)
  3. Ifixit kit (deluxe starter kit!)
  4. Elenco soldering kit (soldering only)
  5. Radio shack soldering kit (soldering only)

Here is the menu of kits that I think would be appropriate. They are all less than $40, most less than $20. I don’t have any attachment to these companies, but they make nice kits.  Please choose one and order it so that you have it in time for class. Feel free to get something not on this list as long as it is a beginner kit (since this is a beginner class). You can read the description and decide for yourself what you want to build; keep it mind that kits with more parts take longer and have a higher chance of failure due to complexity.

  1. Weevil Eye (one of the simplest kits – good for smaller kids or unambitious adults)
  2. Digital Dice
  3. Simon Game (button version)
  4. Simon Game (tilt version)
  5. Blinky single-digit marquee (a little more advanced due to high part count); hackable
  6. Pico Paso noise maker (spectacularly annoying!); hackable
  7. Tiny Cylon LED blinking thing;hackable
  8. Music Game (Has possibility for more advanced hacking)
  9. Useless Machine (One of my favorite things, but actually not that much soldering involved; it’s largely mechanical)
  10. 1-gram piano (Has possibility for more advanced hacking)
  11. ClocKit (Has possibility for more advanced hacking)

Contact me if you have any questions.

 

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Mar 25

Kayaking Near Tofino, BC

The following is a visual representation of why the effort of hauling my gear thousands of miles, fighting through sometimes difficult water and camping in the cold is worth the effort. I’ve just returned from the area near Tofino, British Columbia, where I was fortunate enough to go kayak camping for a few days.

Sea lions off of Blunden island.

A gray whale and her calf surface briefly.

A sea otter takes a break from his ceaseless activity to watch me. They seem to like he turbulent, foamy water, or at least the food they find there.

Dramatic waves, having traveled immense distances across the open Pacific, come ashore at last.

Whales are huge, but not always obvious. There is a whale in this picture… (click to enlarge, as with all these images)

Only when they break the surface or breathe do you really see them, unless they’re doing something dramatic like broaching or fluking, which I didn’t see this time (although I have seen it – see here).

In the calmer waters behind the barrier islands, it’s a different world.

This is the kind of scenery with which I was continually forced to cope… really, how does one deal with this? It’s everywhere you look; it’s there when the sun sets, and still there in the morning.  I couldn’t stop feeling like the luckiest person alive.

Sometimes, this happens:

Numerous inviting beaches await, some with caves or primeval, Tolkeinesque rain forest groves.

Wolves comb the beaches for anything edible.  They approached me at close range while I was camping and I had to shoo them away, but unfortunately I didn’t have a camera nearby at the time. They seemed sleek and well-nourished.  Here are images of some other wolves I saw once.

I like blue.

This next image, although not that impressive, I will never forget, because it was so hard to get.  A 30-knot headwind was blasting mercilessly into my teeth as the tidal current ran against me over a complex bottom, causing confused, turbulent water that pulled in multiple directions with waves popping up unexpectedly to douse me and my unprotected camera.  I had to row forward furiously just to go backwards slowly, but I was determined to get an image of these guys. When I put down the paddle for just 8 seconds (I counted), the wind swung me in the opposite direction.  The motion of the boat, the lack of good light, and the qualities of the camera made it extremely difficult to get a clear image, all while trying to keep right side up and the camera dry.  I took it as a personal challenge to get any image at all, and after all that, when I reached the right spot to take the picture and raised the camera during the 8-second interval, the eagles turned their backs upon me! I shouted “really? That’s the way it’s going to be?”  Yes, that’s the way it was.

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Mar 19

More Port Alberni

Some images looking across the Barkley sound from Port Alberni.

One of the local timber plant’s tiny tugboats pulls a raft of unprocessed logs.

A vessel in the harbor is lit by angled light coming in under the clouds.

A very typical scene from the windows of the office here.

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Mar 17

Port Alberni, BC

Click on images to make them larger.

Leaving the brilliant, windswept wilderness outpost of Flagstaff, I had a good view of the peaks and a few smaller cinder cones to the west.

I touched down in the metropolitan madness of arid Phoenix…

…flew back north over the geological wonderland of Northern Arizona and Utah:

…and touched down again in rainy Seattle.  SEA-TAC is a great airport.  I love the wall of glass, suspended on cables:

Finally, I landed in Victoria, BC, Canada, and drove several hours to Port Alberni, another wilderness outpost.

After getting a night’s rest and putting in a day’s work, I used the remaining light to visit Stamp falls regional park, where there is a roaring waterfall and a fish ladder.

It’s verdant, smells like healthy soil and fresh air, and moss covers everything, as is characteristic of the northwest.

There was this giant, which squirted out of a crevice in a cliff, made a 90-degree turn and shot towards the sky.

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Feb 6

Steamboat rock

Category: Arizona

Here are the pictorial results of a day hike to steamboat rock in Sedona. This is accessible via a poor trail that can go straight up cliffs.  Not for the acrophobic, this one! Step carefully… and look around, there are ancient native American ruins everywhere, hidden high in the cliffs.

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Oct 24

Cygwin’s sshd mysteriously stops working; “operation not permitted”

Category: JHUAPL,Work

This is a technical post just for reference, and hopefully to help out any others who have had this problem.

Several months ago, many PCs on which I have Cygwin’s SSHD installed refused to let me in.  The symptom: when logging in, either remotely or from localhost, my password would be accepted and I’d see the MOTD, but then without ceremony, I’d be logged out without ever seeing a command prompt or an error.  On the server’s windows event log, I saw “operation not permitted.”

After thrashing about for a really long time (months!) I finally hit upon the solution.

First, the problem: it’s something the IT people at work did to my systems.  Every PC presenting this problem had previously worked just fine until some IT department update, after which they all stopped working.  The IT help desk was of no help whatsoever; a problem has to be incredibly obvious before they notice it.  On every PC without the security package, sshd continued to work fine.  I used the same installer for every single PC, so my setup and config was the same – it was something my IT people did that broke it.

Fortunately, there is a way to modify the system to allow it to work again.  I don’t know if it will work in every instance, but in my case, the default owner of a specific directory was at fault, but I couldn’t see this because of the rather cryptic way that cygwin sshd messages are logged by default.

The solution: Change the owner of the directory, and also put sshd log messages in a unix-y place where you can read them from the command line. Here’s the proceedure:

  1. Setup cygwin’s sshd normally by invoking: ssh-host-config -y (If you have been thrashing about trying to solve this problem and have changed permissions and config files, just run the script again to ensure that your setup is reasonable)
  2. DON’T START sshd.
  3. Issue “chown SYSTEM /var/empty”
  4. Uninstall the default sshd service by invoking: cygrunsrv –remove sshd
  5. Reinstall the service and make the sshd output go to /var/log/sshd.log by invoking: cygrunsrv -I sshd -d “Cygwin sshd” -p /usr/sbin/sshd -a ‘-D -e’

I hope this works for you.

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Oct 13

Ant Colony Casts

Category: animals

Sep 23

Pennsylvania countryside

Category: Travel,Uncategorized

Just before taking off for home, I stopped by to visit with my sister in Pennsylvania again, and we got out for a quick walk through the countryside (on a Land Conservancy property near Newtown Square).

Then it was off for another flight across the country.

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Sep 14

A Day Sail on the Gazela

On the east coast for business, once again I made sure to roll through Philly to visit with family. For me, “family” includes the Gazela, a ship on which I have been crew for nearly 20 years. I usually don’t get to sail any more, living so far away, but today was special. We conducted a practice sail between the Ben Franklin and Walt Whitman bridges.  It was a delightful afternoon, with a fine breeze perfect for sailing, not too much river traffic, and lots of sun.

We motored out into the enormous Delaware, but soon raised some jibs.  That’s the battleship “New Jersey” in the background.

Next we raised the lower and upper main square sails.

In the next image it looks like we’re standing on the yard (large wooden horizontal mast-like wood) at bottom, but that is an illusion.  In actuality, crew stands on the footrope – the unoccupied lower main topsail yard’s footrope, a heavy black line, can be seen at the bottom of this picture.

In unison, we lean forward – throwing our feet back as our bellies form a pivot point on top of the yard – and grab a “flake” (fold) of sail. We haul it up, lean backwards – and, holding on to the sail, which is what prevents us from falling – stand upright, then fold the flake on to the top of the yard. Leaning on the folded flake with our bellies, this operation is performed multiple times until the entire sail has been hauled up and folded, accordion-style, on top of the yard, at which point it’s tied with short ropes named “gaskets.”

Here is a rare image with me actually in it.  We’re furling the jibs – sails attached to the boom, or mast that points from the bow (front) end of the ship. It’s one of my favorite places, because you can watch water part around the bow while the ship moves through the water, and at sea, sometimes there are dolphins or pilot whales (which are like big black dolphins) playing in the bow wave.

The Philadelphia skyline seen from mid-river.  If you enlarge this image you can see a tall ship named “Moshulu” which used to haul grain around the horn.  In fact, it was the last wind-powered ship to commercially travel between Europe and Australia, as well as the orient and the US, and several books were written about it.  Now it doesn’t sail; its rigging is nice-looking but for show only, and it is a fancy restaurant that never moves.  But I love that Philadelphia has this amazing ship.  To its right, which a white hull and saffron superstructure, is the Olympia, the original gunboat of the phrase “gunboat diplomacy.” It is the ship from which Admiral Dewey said the famous line “You may fire when you are ready, Gridley,” which launched the crucial naval battle of the Spanish-American war.  Harder to see in this picture in the Becuna, a decorated WWII submarine.  Across the river in Camden, NJ, and shown in another picture in this post, is the WWII battleship New Jersey.

Since there are so many other historic vessels I should mention that the Gazela may be the oldest wooden sailing vessel afloat in the US, and one of the oldest in the world.  Built in Portugal in1883 (although extensively refitted in 1901), she is still sailed up and down the east coast, not as a pleasure vessel, but as a living school to preserve the skills of the era of sail.

I’ve included a variety of images in the gallery below; click to enlarge.

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Aug 13

Blue Ridge Kayak Camping

Category: Arizona

Our first trip to Blue Ridge was a scouting mission for a larger trip which we just completed.  It was a logistical giant, but we pulled it off: 15-20 people converged over hundreds of miles and were rowed or ferried to the campsite about 3 miles from the boat launch.  The weather was perfect, not storming until the last hour when a few of us were still rowing back.  Kids, dogs, and adults all had fun; every night was a party; good food, conversation, and company was the rule.  The Perseid meteor showers were ramping up, so at night we lay back and stared at the immensity of the cosmos – so clear at this altitude – and watched meteors streak across the milky way. During the perfect days we clambered down the sandstone cliff of our castle-like isolated campsite and swam in the emerald waters. We saw western Grebes and Pelicans – odd birds at this location!

Click on any image to enlarge it.

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