James Biederbeck

I am a student, political operative, programmer, and debater. I am majoring in political science, with a minor in philosophy. I currently know the machine languages Python, C, and Wiring. I know the human languages Spanish, Italian, and I know some Japanese.

[jamesbiederbeck]

New Toys, Again.

This Christmas, I got an SDR Raspberry Pi 2, a Raspberry Pi 0, and two ESP8266′s (though one is tied up in the Sparkfun Arduino WiFi Shield) and a Dremel tool. 

The SDR in particular is  a BLAST. I started playing with it first, simply because it requires the least set up. At this point, I don’t have an antenna for it, so I can really only play around with some weak FM radio, and looking for wifi weak spots in my new apartment, but it’s been promising so far. The nice folks in the RTL SDR Subreddit say that the best thing to do is build a planar disk antenna out of some dollar store pizza pans, so I’m thinking I’ll do that next week some time. 

I still haven’t done much with all the stuff from last year. The Yun did make for a pretty nice wifi thermometer, but it really deserves so much better than that. Now that I’m in the new apartment, I’m thinking it might make for a nice home automation hub, especially if I ever get around to buying a Phillips Hue. The up24 was nice, but button popped off the end, and the replacement they sent me had about 24 hour battery life, as opposed to most units’ 14 day battery life. 

Happy New Year! 

[jamesbiederbeck]

8 oz of sweet mexican black tar... coffee?

I love coffee. The problem is that there's not enough. I got an espresso maker for Christmas, and now my family complains because I have single handedly doubled our household coffee consumption. My daily cup of coffee was quickly replaced by a latte, and soon by my twice daily triple shot depth charge. But now, I've finally discovered how to make coffee that I have to dilute to my desired concentration. 

I recently picked up Homeland, by Cory Doctorow, (which I could not put down). He spends a significant portion of the book touting the wonders of cold brew coffee. Cold brew is magical because it's sweeter than regular coffee as a consequence of the fact that it's never exposed to hot water, but it also comes out more caffeinated. 

In order to cold brew coffee you just leave coffee grounds in some water in an airtight container in your fridge overnight. The only hard part is separating your grounds from your coffee in the morning. It seems a french press is the best way to do this. I've tried ugly combinations of strainers and coffee filters, and I always end up making a mess. I got to use a french press the other day, and it worked flawlessly. 

Just make sure you check the concentration before you drink it, or else you'll have a bad time. 

How do you brew your coffee?

[snippets-of-code-blog]

After much googling around, I found two popular ways to add syntax highlighting into Tumblr:

Alex Gorbachev’s Syntax Highlighter

Google’s Prettify

I tried the Syntax Highlighter at first and spent a really long time trying to get it to work. When it finally did, it slowed the loading...

[jamesbiederbeck]

coding, tumblr, hacking, programming, blogging

[jamesbiederbeck]

How to solve "Could not connect to YunServer 146 Connection refused" when using Yun's REST API

If you’re having this error, here are some basic steps to follow:

Make certain you’ve set the REST API to “open” after logging into the Yun’s webpanel.

Make sure you’ve uploaded the “Bridge” sketch

If you have recently changed network settings, do a power cycle of the arduino

The last bullet point is my most common cause of the error, since I like to lug the Yun around a lot to play with it in my spare time at school/ at the girlfriend’s place.

[jamesbiederbeck]

Here's my not (yet) pretty current Yun setup. Top right: a thermistor and voltage divider to read the temperature (accurate to a 6th of a degree at 25C), and an rgb led for simple color coded notifications over wifi. Botom left: 32GB microSD card. This is where the yun keeps its OS, because the yun's internal memory has a limited number of writes. This will extend the life of my yun significantly.  Next up: SQL database for storing temperature readings, and move breadboard onto PCB shield.

[jamesbiederbeck]

On Death Rays and EMP's

A user on reddit recently asked 

"Is there a type of gun that uses induction heating? If so that'd be pretty neat."

I liked the question so much, I decided to make a blog post out of it.

It sounds like you want a deathray.

That's cool, I'm a fan of deathrays myself. I just don't see why you'd want to use a big ugly electromagnet that only affects metal for your villainous plots. I prefer to use my deathrays from far away. Lasers are great for this, and so are parabolic mirrors and magnifying glasses if you're comfortable getting a little closer. Supposedly Archimedes used giant mirrors to focus sunlight on the then wooden ships to light them on fire. What lasers, mirrors, and lenses like magnifying glasses have in common is that they concentrate energy in space, through they do so different means diffraction (lenses), reflection (mirrors), or controlling something called spatial coherence by controlling frequency (lasers). Let's not worry about that last one too much though. It hurts my brain.

You could however make an induction bomb. We call this an Electromagnetic Pulse. While magnets (more specifically, changing magnetic fields) are great, their tendency to create fields rather than rays or beams make it difficult to be destructive with them. If you want to do this, you need to be quick about it. Very quick. Too slow, and any heat you create just gets conducted into surrounding material, or radiated away as light. Since we're not concentrating in space, we NEED to concentrate our energy over time. Hence the pulse. The result is that we vaporize any metal too small to dissipate the heat effectively--think about what's inside of every computer. Now our technology is set back to the days of Archimedes.

In general, when you want to be destructive, you'll find it best to concentrate your effort in time or space, or better yet, both. Consider that a typical bullet weighing 4.2 grams moving at ~1000 m/s has the same roughly amount of kinetic energy (aka momentum or mass times velocity) as something 1000 times heavier that's moving 1000 times slower, say, a 4kg (9lb) bowling ball moving at 10 m/s a second. For reference, this is about how fast it would go if you had dropped it from 4 meters (16 ft). Again, they have roughly the same amount of energy, but I'd rather have the bolwing ball dropped on my head.

These sorts of weapons (except for the actual gun used in my bowling ball comparison) are called directed energy weapons, and there's a [great episode of Future weapons](https://www.youtube.com/watch?v=Fvu08Y9XJ0U) on them.

Thanks for reading. I really enjoy writing these sorts of posts, and hope to do more soon. Follow my blog to meet all your deathray needs.

[jamesbiederbeck]

Controlling the Arduino Yun using Python scripts run locally and the REST API

Ever since I learned python, I dreamed of using it for robotics. Ever since I started playing with Arduinos, I wanted to program them in python. And now,I'm very excited to have accomplished that, but it's a rather kludge solution. But the point is, now I can control (and read) any pins from Python! 

I've uploaded the bridge sketch included with the IDE and I'm playing with using it to control the arduino. This is probably much slower to do, and I should probably use the bridge directly rather than running API calls over http, but it's a very quick solution I hacked together. For many applications, this will still work pretty well. 

Here's the blink program, implemented in python:

#blinkYun by James Biederbeck 1/3/2015 #you should change localhost to youryun.local if you're not running #the script on the device. import time import requests yunaddress = "localhost" url = "http://"+yunaddress+"/arduino/digital/13/"

def blink(boolean): if boolean: return requests.get(url+'1') else: return requests.get(url+'0')

for i in range(10): blink(1) time.sleep(1) blink(0) time.sleep(1)

I did digital writes this way, and using the requests Response.elapsed attribute from the requests module, I found that the typical time for reponse was 330 ms. Not ideal, but if all you're doing is turning on lights over wifi or something of the sort, this is very reasonable latency.

Obviously you would replace these http requests with actual bridge communications for a more serious project, but I'm curious how much of this time is spent doing the digitalWrite, because pinging localhost takes less than half a millisecond 

EDIT: Simply using the yun's ip solves the problem, so it probably has something to do with DNS lookups.

[jamesbiederbeck]

Project Update!

Well, it's the holiday season again, which means new toys, and new toys mean... You guessed it! New projects! I haven't updated in a while, so I'll also post updates on my other projects.

Arduino Yún

Jawbone UP24

NFC Tags (stickers and key chains) and a book on using rfid for shenanigans.

Espresso Maker

Arduino Yún

I'm particularly excited for this one. I've already starting playing with it and it feels more like setting up a router than playing with an Arduino. It's weird. The Yún has a USB host port, WiFi, and Ethernet, all built in. When you turn it on, it makes it's own wifi, so you just have to connect, and load up arduino.local in your browser, and it presents you with a configuration page. It reminded me a lot of setting up my Chromecast. 

I'll write a review after I've finished playing with it some more, but this is definitely going to be fun. This will be where I finally start toying with "the internet of things". 

Jawbone UP24

Got this one from the girlfriend. It's little more than a button and an accelerometer with a bluetooth connections that live in a bracelet on your wrist. I've been reading about this for a little bit, and it turns out that you can do some pretty cool stuff with it tasker, and IFTTT. I've heard of people using it for things like snoozing their alarms on their androids, and I'm thinking I'm hoping to get access to the raw accelerometer data over bluetooth. I've previously used the Chronos 430 for a sort of wireless hand gesture mouse, and I think I can do it better with the Jawbone.

NFC Tags

I think I'm most excited about these. (Update, I got a snowboard. that's the most exciting. or the yun.) I have been playing around with Tasker a lot the last few months. I recently discovered EventGhost which is just magic when integrated with autoremote. That deserves a post on it's own. But the NFC tags have immense potential because I can automate my phone based on its location in my home. My first project is to copy this guy's setup which is pure magic. He makes it so he has to put is phone on his bathroom counter to turn of his alarm. Other redditors have discussed using it to turn on bluetooth in their cars. I have high hopes for this.

Espresso maker:

I get to make delicious, and stronger coffee. That means more productivity, and even more new projects!

[jamesbiederbeck]

Understanding Latency vs Bandwidth

Bandwidth (more is better): The amount of data that can be carried in a given amount of time, EG 25/Mbps (megabits per second).

Latency (lower is better): The delay between sending and arrival. Typical should be somewhere less than 50ms, ideally closer to 10, depending on where the website is hosted.

Examples to differentiate the two:

Low bandwidth, low latency

You pass a note to your friend. It’s 30 characters. It takes you 1 second to pass the note. The bandwidth is .0000003 mbps per second, and the latency is one second. Very low bandwidth, but ok latency (for a measly human).

High bandwidth, High latency:

You want to give some books to a friend, but he lives down the street, so you have another friend drive the books over. The books have 4,000,000,000 characters (that’s roughly 4 GB for my geeky friends), and it takes 1000 seconds  to get there. Now the latency is 1000 seconds, but the bandwidth is much, much higher, at  4 mbps.

This means if you fill your car up with books, you can deliver information with a bandwidth comparable to the internet service most people pay for, at a fraction of the cost, if you don’t mind sacrificing latency. Unfortunately, note since 1998 has anyone been willing to wait 1000 seconds, or even 60 for a page to load.

[jamesbiederbeck]

Got a Digispark and RGB shield for Christmas. It's programmable using arduino code, and it's the size of your thumbnail. 

It's little more than an attiny85 and a voltage regulator. It plugs straight into a usb port. 

[insteadofwatchingtv]

How Does a Transistor Work?

[usefulknowledgecodex]

Add Ardunio-Powered Brake Lights and Turn Signals to Your Bike

Whether you’re biking or driving, everyone has to share the road, and the goal for everyone is to get where you’re going in one piece. This DIY project brings a little technology to your two-wheeler and adds brake lights and turn signals to each handlebar so drivers or other bikers always know when you’re slowing or about to turn.

Read more…    

http://q.gs/4USK8

[onlinecounsellingcollege]

Stop trying to ‘get it together’. The biggest lie we’re told when we’re growing up is that soon as we’re adults, as soon as we’re in college, finish college, get that job, have that steady income, find that someone special, ‘find ourselves’, find that perfect house, get that retirement fund, have those children, everything will fall into place. Here’s a secret: it won’t. Every new development in your life, good or bad, big or small, will come with its own very special set of challenges. The sooner you accept that, the better off you’ll be.

Unknown  (via unicaa)

[jamesbiederbeck]

Got Bored Yesterday. Made an Ultrasonic Tape Measurer.

It's just not neatly packaged or anything. It has a maximum range of about 56 inches or so. I could probably extend it using software. I've already disassembled it though. The screen is an I2C 20X4 LCD screen from Sainsmart. I think I broke the backlight when I powered it without a current limiting resistor. Tutorial after the break. Code at the bottom.

So, You'll wanna wire the grounds of the SR04 and LCD screen to the Ground headers on the Arduino. If you're using a 5 volt supply (like a USB port) you can wire one of them to vin, and the other to +5v, though this is a bad practice. If you do this, forget, and switch to a 9v supply, you could damage something. It's safest to use a breadboard. 

After you've done this, wire the trigger pin to 12, and echo pin to 13. Or anywhere really, just make sure it matches the code's #define statements. I'd advise against 0 or 1 since those are used for USB, and won't play nice with Serial communication. 

Lastly, wire the screen (if it's like mine, an I2C version) such that SDA goes to A4 (yes, Analog) and SCL to A5. Next, just copy the code, and upload it. Change inches to CM if you desire. There's instructions for this in the comments.

Code: http://pastebin.com/8LeDcieB

[jamesbiederbeck]

On the Constitutionality of Warrentless Wiretapping and Surveillance Conducted by the NSA

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

-The 4th Amendment to the United States Constitution 

The question is, does 'secure against' mean free from disturbance, or private? In the historical context, searches meant a person digging through your house, not listening at your door. Eavesdropping is the closest historical analogue we have to modern wiretapping and similar surveillance.

In Katz v. United states, SCOTUS ruled that it's a search (and therefore unconstitutional) when a person expects privacy in the thing searched, and society believes the expectation reasonable. Is that expectation still valid if the person was using their computer in a public place? What if they were using their own home's wifi, but they didn't protect it with a password, or encryption? The supreme court seemed to rule in 2005 (Clapper v. Amnesty International) that no individual could bring suit if they weren't individually, or at least selectly targeted, leaving little reprieve for the broad spectrum surveillance conducted by the NSA.

In essence, the law right now seems to be "You can't search anyone without a warrant, but you can search everyone without a warrant." The law still has a lot of catching up to do. Unfortunately, by the time it catches up, the NSA may have already gotten better at hiding.

[jamesbiederbeck]

My current project. Right now it's just an Arduino and an h bridge chip. Today I'm going to add steering. I got the car for $4 at good will and pulled out all the guts.

[jamesbiederbeck]

Wow.

Haven't updated in a while. I think I'm the only person who wants to keep doing anything with this project. Which makes me sad. 

I'm still learning programming right now, but my personal development is going in a little different direction from this game project of ours.

I just got an Arduino and Raspberry Pi for Christmas, so be prepared to hear about that stuff for a while.