So let’s say you have a private LAN running in your secret underground lab. Maybe you’ve got a Linux box hardwired to a WiFi router, and maybe a Mac or Linux laptop floating around somewhere, and you need a quick way to transfer files or execute shell commands remotely.

What you need is SSH, the Secure Shell. SSH is a powerful tool which allows secure remote login over insecure networks. It provides an encrypted terminal session with strong authentication of both the server and client using public-key cryptography. This tutorial will cover the basics of SSH’s most useful features:

• Logging into a remote computer over a secure connection.
• Transferring files and directories between computers over a secure connection.
• Enabling public-key authentication.
• Passwordless authentication for use with scripts and cron jobs.

The following assumptions are made about the reader:

• You know what a terminal/command line/shell is and how to start a session.
• You have at least a basic familiarity with Linux/Mac command-line syntax.
• You’re on a private LAN with access to at least two Linux/Mac computers (or, you have a user account on a remote server that accepts SSH connections).

As always, comments, corrections, and suggestions for improvement are appreciated.

Installing OpenSSH

The Ubuntu (and MacOS X) flavor of SSH is called OpenSSH, a free, open-source implementation of the ssh protocol. It consists of two basic components, an openssh-client and an openssh-server. SSH clients communicate with SSH servers over encrypted network connections.

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LightScribe is an innovative technology that uses a special disc drive, special media, and label-making software to burn labels directly onto CDs and DVDs. The labels are laser-etched, not printed, so there’s no ink, no smudging, and no peeling.

LightScribe lets you create one-of-a-kind designs with your own photos, text, and artwork. The days of hand-labeling or printing stickers for your CDs and DVDs are over.

This short tutorial will describe how to install and run LightScribe software on Ubuntu. These instructions are tailored specifically for Ku/Xu/Ubuntu 64-bit users, since the LightScribe software is designed for the 32-bit architecture. Where necessary, alterations for 32-bit users are included.

What You Need

Before downloading anything, make sure you have the necessary hardware and materials at hand, or you may have to make an emergency trip to your local big-box electronics store.

LightScribe hardware

LightScribe-enabled disc drives do double duty. The same laser that burns your data will also laser-etch your customized CD/DVD labels. LightScribe-enabled CD/DVD burners are ubiquitous these days. You may already have one.

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I recently soldered up a Boarduino from Adafruit Industries. Boarduino is simply an Arduino clone with a smaller form factor, designed to plug directly into a breadboard rather than giving you the female headers of the original. I thought I’d post a few photos of the process.

I really like the idea of the Boarduino, because I found I was doing almost all of my prototyping on a breadboard, and it seemed like I was always trying to figure out new and different ways to anchor the big Arduino down.

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image: Randomskk / cc by-sa

My Weller WES51 arrived today (w00t!), and in celebration, I thought I’d compile a list of my favorite soldering tutorials around the web.

How to Solder Correctly: An excellent starting point, thanks to a detailed seven-minute video and lots of close-up images.

Soldering Tips (PDF, 284K): Ten pages of required reading by Tom Hammond, with advice on tool selection, tip tinning, component positioning, and solder types. Lots of great diagrams for all of us right-brained learners.

Basic Soldering Guide: From Everyday Practical Electronics magazine, discusses tool selection, soldering methods, and — perhaps more importantly — de-soldering!

Soldering Basics: This detailed tutorial from SparkFun.com includes several short videos and lots of pictures, then lets you really get your hands dirty with step-by-step instructions on soldering up a basic RS232 shifter board kit.

Surface-Mount Soldering: More and more components and ICs are shrinking in size and doing away with through-hole pinouts. Just go easy on the coffee and you too can solder SMDs!

Basic SMD Soldering: A whopping 8-part solder-a-thon from SparkFun. Starts with tools, moves into surface-mount soldering techniques, then takes it up a notch with hot-air rework — for when you mess up.

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Although the Arduino platform is ideal for standalone applications, it really comes to life when interfaced with a PC. Connect Arduino to a personal computer and you instantly add a ton of versatility and processing power to your project.

This tutorial will describe how to use Arduino to control a bank of four independent RC servos with your PC (or Mac, or *nix Box), using a USB cable and a modular Arduino-Python software stack.

The following discussion builds upon concepts presented in two previous articles, “Arduino Serial Servo Control” and “Joystick Control of a Servo.” As always, comments, critiques, or suggestions for improving or adapting this code are welcome and appreciated.

Project Outline

The primary goal for this project was to create a software stack that allows simple and flexible control of multiple servos from any type of Python script.

The solution has two basic components: (1) an Arduino sketch that waits for serial input from a connected PC, then moves each servo to its commanded position, and; (2) a Python module on the PC that opens the serial connection and formats the data packets expected by the Arduino.

Any other Python program written to sit on top of these two layers need not worry about the messy details of serial communication, but rather can just say something like, “Move servo #2 to 90 degrees.” Or, more precisely:

servo.move(2,90)

Easy, right? Let’s get started.

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My first computer was an Apple IIc. I was thirteen years old and, at that age, it was one of the most beautiful things I had ever seen. It had a gorgeous, green-on-black display screen, 128KB of RAM, no hard disk, and a Slim-line internal 5.25″ floppy drive into which you loaded whatever version of Zork you were in the mood for, and fired it up. All software was written in Applesoft BASIC, and although there was no official term for it at the time, everything was open source.

A simple Ctrl-C (or some such keystroke) was all that was required to break the flow of whatever program you were running and take a peek under the hood. I wrote my first computer program on the IIc. There might have been limits to what that little machine could do, but there were no restrictions. If you could imagine it, you could build it, and if you didn’t know quite how to build it, you just found someone else’s program that did something close, and figured out how they had done it. The Apple IIc was more than a tool, it was a teacher.

In college I used PCs and Macs, none of which I owned, of course — it just wasn’t expected in those days — and I reluctantly deciphered the library’s Unix terminals for the sole purpose of emailing friends with Pine. Until my junior year, by which time I was accustomed to using the university’s computer labs for my paper-writing and other needs, I kept that old Apple IIc around, with a dot-matrix printer, just in case.

It wasn’t until after graduation that I could finally afford (almost) to purchase my own computer. After buying and returning a couple of defective laptop PCs from a big box electronics retailer, I finally decided to go back to Apple, and I sprung for a Powerbook G3. It was beautiful, and it was definitely a Mac, but something was missing.

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Hulu.com is a brand-new, free, ad-supported streaming video service which combines content from more than fifty providers including FOX, NBC, MGM, Sony Pictures Television, Warner Bros., Lionsgate, and more. Although Hulu has been live since October, the site just emerged today from its private beta-testing phase and is now open to everyone–as long as you live in the United States.

Hulu lets you watch full-length feature films like The Big Lebowski or The Usual Suspects, or recent television episodes of Family Guy or The Office. Plus there’s a fair number of canceled cult classics like Firefly.

Both shows and movies are interrupted with brief commercial breaks, but these can be –ahem– suppressed, and they are definitely less intrusive than those on regular commercial television. Content on Hulu is certainly limited, but they’re just getting started, and I must say, with respect to the movie selection, I’d be inclined to browse Hulu for decent flicks before I’ll suffer the crap from the Netflix “Watch Instantly” archive.

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