Philly Tech Week – We’re Booked Solid

Monday – MMMM  Microcontroller Madness

Tuesday – DIY Music Night

Wednesday – Open House

Thursday – Game Night Featuring Tetris Arm Wrestling Tournament

Friday – PTW Gala demonstration (offsite)

Events at Hive76 Monday through Thursday start at 7pm and 


Friday Gala Ticketing information available here.

Magnetic Dip, Illustrated

I was surprised at the absence of a concise illustration of magnetic dip available on the internet, so I cobbled together a short 3D animation using the excellent free software Blender. Magnetic dip is a very simple phenomenon but one which can quickly get confusing since it deals with 3-dimensional fields through space that can be difficult to visualize. The gist of it is that the Earth’s magnetic field lines are only parallel with the ground around the equator, and everywhere else the field lines actually dive downwards into the Earth by some angle, the steepest of which are found at the magnetic North and South poles. In the Philly area this angle is surprisingly steep, about 67 degrees below the horizontal — it’s actually more vertical than horizontal! This means that in areas far from the equator, tilting to the East or West will result in a compass error since the needle can align more closely with the magnetic field by deviating from the projection of the field lines onto the ground, which is what we normally think of as North. Tilt to the West in the Northern hemisphere, and the compass needle will tilt to the West as well.

It gets even more confusing when you are talking about traditional non-gyro-stabilized compasses, such as those normally found in small aircraft. The compass needle is usually weighted carefully such that it rests level with the ground under normal circumstances, but this means that when you accelerate in certain directions, that weight’s inertia keeps it lagging behind somewhat, resulting in yet more compass errors. These acceleration effects are not directly the result of magnetic dip, but they are partly the result of an incomplete attempt to deal with magnetic dip. Normally pilots are just taught to remember that this happens and vaguely what to do about it, but if you level out and stop accelerating the problem takes care of itself.

Blender allowed me to put this simple animation together in a very short time. It has a challenging learning curve, but it is a very powerful set of tools. Hopefully this animation will be useful to somebody out there other than me.

LinkedIn is selling your clicks and violating its own Privacy Policy

Did you just click that link? If you were signed in to LinkedIn, and if the link was to a user profile on the same site LinkedIn, you have just created a revenue generating stream for LinkedIn where they will apparently sell information about your viewing habits that are matched to your user profile to other users of the same site.

As advertising for the LinkedIn Premium for-pay Service called “LinkedInPro” they advertise a feature:

Who’s Viewed Your Profile: Get the full list
Get the complete list of who’s viewed your profile with Profile Stats Pro. You’ll also see how your viewers found you, and learn more about the people interested in you.

This is a feature of their all of their Business, Business Plus, and Executive for-pay services, which range from $24.99-$99.95 per month. The only possible way individual users of the site can know who viewed you—the “full list”—is if LinkedIn is converting its web traffic logs of all logged in users’ clicks explicitly as a means to sell the information to other individuals. LinkedIn never asked permission to show views to other users.

In addition, LinkedIn appears to have violated its own user policy with this new “Pro” feature for sale. Their privacy policy states:

We do not sell, rent, or otherwise provide personally identifiable information to third parties without your consent except where it is necessary to carry out your instructions (to process your payment information, for example) or as described in Section 2 of this Privacy Policy. Also, we may share information with affiliates (like LinkedIn Ireland, Limited) to provide the Services. We also provide you with the means to control whether or not your contact information is viewable to other Users through your profile.

Hey LinkedIn… guess what? Any user on your site, necessarily, is a third party.

That means LinkedIn is both actively tracking everything you click on specifically as a means to be sold as personally identifiable information to other users of the site, while at the same time promising not to do so.

At this point all you can do is deactivate your LinkedIn account (UnLinked™?) since their customer service does not respond to inquiries. What a crock.


Some people appear to be misunderstand the situation. To be more clear:
From the title: LinkedIn is selling your CLICKS. They are absolutely selling your clicks to third parties. They have unilaterally decided that your browsing history on their site is for sale to any other user on the site.

Many websites do this automatically, but in an anonymizing way: “5,000,000 Youtube views” and the like. The common expectation is that views will be anonymized. What makes this unique is that LinkedIn advertises that they are MATCHING a user’s individual clicks (and presumably the day and time of those clicks) to that user’s online profile on LinkedIn (the “who’s viewed your profile” bit in their advertising) for these third parties without your consent.

This is not publishing your “likes” or your private information. It’s publishing your CLICKS and PAGE VIEWS that are MATCHED to your LinkedIn profile. LinkedIn is publishing your browsing history. On top of that, they are selling it.

Totally uncalled-for by LinkedIn.

Tonight@Hive76: Hacking Your Lawyer: A Primer

Our speaker series continues tonight at 7:30PM!

We are proud to welcome Lea Rosen, Rutgers-Camden law student, researcher, and writer, to Hive76 to present a talk entitled, “Hacking Your Lawyer: A Primer.”

“Ever feel like your questions elicit boring and disappointing answers from lawyers? It happens all the time, and it feels counterintuitive – the stuff you are working on is complex and exciting, and you know the law is complex and kind of interesting. Your gut’s not wrong – your questions are. I’ll explain why we talk the way we do, and how you can learn a couple simple lessons to help frame your questions in a way that will draw out the information you really want. “

In addition to her main presentation, she will also be discussing some of the topics that were brought up on our mailing list, like the legal implications of hacking the things that you own. There happens to be a DMCA Rulemaking Session this year, so she will discuss how the DMCA works and what it takes to get legal protection for hardware hacking. There will be a Q&A section afterwards because I’m sure we’ll have some questions. 🙂

A little more about Lea:

Her big motivation is to break down the cultural boundaries between technologists, hackers, lawyers, human rights advocates, activists, and theorists. She provides research assistance for Evgeny Morozov, author of The Net Delusion, and Greg Lastowka, Professor at Rutgers School of Law, Camden and author of Virtual Justice[pdf]. She has interned at the Electronic Frontier Foundation and in the Federal District Court in Newark, NJ. She volunteers with the Philadelphia ACLU and the National Lawyers Guild AnoNLG project, and she co-founded of the Rutgers Cyberlaw Society. She has written on the interpretation of software licenses by the 9th Circuit, encryption and border searches, and the privacy and liberty implications of domestic UAV deployment. She also had the opportunity to write an FAQ for the Yes Men! She has her BA in Humanities and will be getting her JD this May from Rutgers-Camden.

See you tonight!

UPDATE: Lea has informed me that Greg Lastowka’s book, Virtual Justice is available for free here[pdf]. It was released under a Creative Commons license! Nice! Hard copy available from Yale University press here.