Wednesday, June 6, 2007

101 Essential Freelancing Resources


Recent article over at FreelanceSwitch listed a huge pile of tools and resources for freelancers. Having gone independent myself as of January 2007, I found this article interesting and shared it with a few other freelancers. It's been universally well-received, so figured I'd just post it here so everyone could benefit.

101 Essential Freelancing Resources

Note: Reader contributions have driven the count up to 126 resources, from what I understand. And the article has been translated into a few other languages; sounds destined to be a classic!

Monday, May 28, 2007

Amateur Radio: 5,200 miles on 50 watts and a $2 antenna


Lately I have been getting prepared for the annual ARRL Field Day, which is an annual operating exercise and public showcase event for the amateur radio world. Amateurs all over North America will set up in campgrounds, parking lots, and fields and attempt to make as many contacts as possible using various "modes"; everything from Morse Code and "phone" (what normal people would call voice, talking into a microphone) to exotic digital setups which use computers connected to radios. My club (the Northern California Cactus Radio Association) will operate as K6SRA from a campground in Henry Coe State Park, near Morgan Hill CA.

I'll be running the digital station this year, and plan to use (in addition to the usual PSK31 and RTTY setup) a very new mode called JT65A-HF. JT65A isn't new to amateur radio as it's been used for a while for "moon bounce"; and yes, I mean literally for bouncing signals off the moon. Earlier in 2006, a few people decided to transmit JT65A signals over the HF bands; primarily 20 meters (14.076 MHz) and 40 meters (7.076 MHz). In only a few months this new mode has exploded in popularity, primarily due to the very high sensitivity afforded by a Reed-Solomon forward error-correction algorithm implemented this mode. It's mathematically provable that JT65A signals can be detected with 100% certainty even if the received signal is -22 dB under the noise floor.

In preparing for working JT65A-HF on Field Day I've been learning to use an application called WSJT which is used mostly by the moon bounce and meteor-scatter folks but now also HF enthusiasts. I've made some amazing contacts this way; just tonight I logged a contact with a guy in Australia using only 50 watts of power and a homemade antenna I built with $2 worth of parts I had lying around my garage. This is the equivalent of someone being able to see a 50 watt light bulb from space at a distance four times that of the International Space Station, or of someone talking from San Jose CA to San Diego CA on a CB radio. I expect we'll be seeing a lot more of JT65A in the HF bands, especially as radio amateurs suffer through the poor radio propogation conditions created by the current solar minima.

Update (15 June 2007) : I just beat my Australia record with a solid contact to ZS6WN in South Africa. 10,526 miles, same power, same antenna!

Update (24 Sept 2007) : WA3LTB has created a video demo of WSJT and posted it to YouTube.

Wednesday, May 23, 2007

Spectrum


Interesting articles about upcoming 700 MHz spectrum auctions over at Spectrum Matters, where Nick accurately notes that this is an insanely important change that nobody really knows about. There have been a few under-the-fold articles in the San Jose Mercury News, but mostly these just talked about the impact to next-gen systems like WiMax. The real and underreported story here is that some of this spectrum will get set aside for a nationwide interoperable emergency communications system, and with any luck we'll see this system deployed sometime between now and when my newborn daughter graduates college. The issue is important enough that the Wireless Communications Alliance has created the Emergency Communications Leadership and Innovation Center dealing specifically with this topic.

For the uninitiated, the issue at hand is this. In the past few years we've seen examples of disasters (Sept 11th, Katrina, Florida) which have overwhelmed the communication capabilities of the local emergency response infrastructure. Well-meaning people from around the world sent teams into these areas in a desire to help, only to find that they could not communicate with other groups or even the locals. People like Brian Steckler from the Naval Postgraduate School had to create ad-hoc "hastily-formed networks" to replace some of the missing infrastructure, and amateur radio operators acted as relays between agencies whose radios could not interoperate.

These problems occurred after disasters which "only" claimed a few thousand lives. What if we have a disaster (tsunami, pandemic flu, meteor strike, terrorist attack, etc) which claims tend of thousands of lives or even (God-forbid) millions? How will the responding agencies communicate? So the government (in a rare display of forward thinking and long-term strategy) has decided that once analog TV is shut down some of that spectrum will go to this nationwide interoperability system. Of course, not everything thinks this is a great idea.

Is it real? Will it survive a possible party shift in the White House come 2008? Will we see it in our lifetimes? Time will tell.