Archive for the ‘Radio’ Category
SunSPOTs with ham radio APRS
Sean Sheedy has a cool post about the possibility of using Sun Microsystems’s SunSPOT technology with amateur radio APRS technology.
SunSPOT at its simplest looks like this: a processor board that includes a small Java based executive and a 2.4GHz RF link, and a sensor board that includes a couple basic sensors plus some general purpose I/O to interface to external third party devices. The development kit is not cheap ($550 USD), but is comparable in price to what you’d pay for a quality scratch-an-itch kit radio (think Elecraft). The dev kit also comes with all the Java libraries to get started programming.
Pretty cool.
[tags]ham radio, aprs, sunspot, embedded java[/tags]
GNU Radio podcast
Recently I had the good fortune to chat with Eric Blossom, founder and driving force behind GNU Radio. We recorded this technology overview conversation, wherein we chatted about what GNU Radio is, some development issues, and future work.
GNU Radio has come a long way since its inception, and now includes a growing, dedicated community of developers and RF experimentalists. Eric has been instrumental in this growth, but so, too, has Matt Ettus with his open hardware platform USRP. USRP gives GNU Radio developers a common hardware platform on which to meet and grow new apps.
GNU Radio is easily one of my favorite open source projects anywhere. If I can only get time to do some GNU Radio development myself. Anyway…
- The Ogg Vorbis version (8Mb). If you can play Vorbis media (xmms), please fetch this version and save me some bits.
- The mp3 version (27Mb).
[tags]gnuradio, software radio, eric blossom[/tags]
Digital voice over HF
Every once in a while I feel compelled to post G4GUO’s work in digital HF voice. Listen to this decoded sample.
This is clean digital voice over links subject to ionospheric disturbances.
Remarkable.
[tags]ham radio, digital radio, hf, amateur radio,g4guo[/tags]
Google analog design job: ham radio experience a plus
Google is looking for analog designers. Ham radio license a plus.
[tags]ham radio, google, analog design[/tags]
Ham Google mashup: hams by zip code
Very cool Google mashup of hams by zip code.
On the same site, there is a mashup of Find Frequency by zip code. Not sure what that is, but it sounds interesting. Entering my zip code apparently exceeded a Google Maps threshold of some sort, as a warning was displayed along with no results.
[tags]ham radio, mashups,google maps[/tags]
Douglas Galbi on radio spectrum rights
Economist Douglas Galbi posted a comment to my Pulver blog support for an Internet Field Day. Mr. Galbi writes on ideas that shape public policy from a spectrum management perspective.
In his paper Revolutionary Ideas for Radio Regulation, he discusses important points of amateur radio and how amateurs consider their freedoms in relation to how the Internet hacker considers his or hers.
This is good reading, and serves to inform the judgement about the future of all radio, including amateur radio, and what that future of what one might call the individual’s radio looks like. As for myself, a free individual, I believe I have some natural right to radio spectrum, and am uncomfortable with the notion that we enjoy, that we experience, amateur radio solely because the government says we can. I have a foot in each world of amateur radio and the Internet. I value both and am concerned over both, as many readers must surely be. So this post is an invitation to reconsider the nature of amateur radio, try to understand where it’s heading, and whether its reason for existing should be revisited in law. Big ideas and questions. But as self governed, we’re up to it.
On amateur radio:
Public service is also an important part of hams self-understanding. Hams have long provided emergency communications for local community events and in response to natural disasters. Hams have also contributed significantly to advancing radio technology, such as pioneering early high-frequency communications and popularizing packet radio. Some hams currently communicate via Morse Code and single-sideband voice communications, methods of communications that have been in use for over half a century. Other hams explore digital signal processing, software-defined radios, moon-bounce communications, and communications using specially designed earth-orbiting satellites. The three-million hams worldwide form a community with a strong sense of tradition and identity. Amateur radio has created for hams opportunities for social interaction, for serving the public, and for exercising engineering creativity. Hams appreciation for the freedom they have found in amateur radio, and their dedication to preserving it, cannot be doubted.
To a remarkable degree, hams understand their activities to be dependent on government license. This view goes all the way back to the beginning of radio. The development of radio implicitly raised the question of whether persons have some natural rights to communicate by radio. Most governments, and amateurs, seemed to assume that persons do not. Nonetheless, absent effective means of suppression, amateur radio developed naturally, through personal curiosity and creativity. About 1912, there were roughly 8000 amateur radio users and 230 amateur radio clubs in the U.S.[21] The U.S. Radio Act of 1912 was hailed as a great victory for amateurs. An amateur activist/magazine publisher declared, The amateur had at last come into his own . Uncle Sam has set his seal of approval upon the amateurs wireless…, and of course, the entire credit for obtaining the amateurs rights belongs to [the author] [22] Here is what the Act said regarding amateurs rights:
Ten years later a historian asked, without even a whiff of self-consciousness, What has the amateur done in the past ten years, to justify the privileges granted him by his government?[24]
On the Internet:
An informally recognized hacker-leader performed another dramatic challenge to authority:
Stallman wore the button proudly. People curious enough to ask him about it received the same well-prepared spiel. My name is Jehovah, Stallman would say. I have a special plan to save the universe, but because of heavenly security reasons I cant tell you what the plan is. Youre just going to have to put your faith in me, because I see the picture and you dont. You know Im good because I told you so. If you dont believe me, Ill throw you on my enemies list and throw you in a pit were Infernal Revenue Service will audit your taxes for eternity.
Those who interpreted the spiel as a word-for-word parody of the Watergate hearings only got half the message. For Stallman, the other half of the message was something only his fellow hackers seemed to be hearing. One hundred years after Lord Acton warned about absolute power corrupting absolutely, Americans seemed to have forgotten the first part of Actons truism: power, itself, corrupts. Rather than point out the numerous examples of petty corruption, Stallman felt content voicing his outrage toward an entire system that trusted power in the first place.[42]
Elsewhere, this hacker-leader presents himself as a general, writing:
some of my cities have fallen. Then I found another threatened city, and got ready for another battle. Over time, Ive learned to look for threats and put myself between them and my city, calling on other hackers to come and join me.
We cant take the future of freedom for granted. Dont take it for granted! If you want to keep your freedom, you must be prepared to defend it.[43]
Another hacker-leader wrote and made freely available on the Internet a fourteen-page article, How to Become a Hacker. The substance of the article begins this way:
Hackers solve problems and build things, and they believe in freedom and voluntary mutual help. To be accepted as a hacker, you have to behave as though you have this kind of attitude yourself. And to behave as though you have the attitude, you have to really believe the attitude.[44]
The article then offers a modern Zen poem for inspiration, and advises: So, if you want to be a hacker, repeat the following things until you believe them . Although exactly what should be repeated is not entirely clear, this appears to be the litany:
The world is full of fascinating problems waiting to be solved.
No problem should ever have to be solved twice.
Boredom and drudgery are evil.
Freedom is good.
Attitude is no substitute for competence.
The article then goes on to advise on how to acquire hacking skills and on socially valued uses of these skills.
Hackers and others actively engaged with the Internet would consider government licensing of Internet users to be an outrage. This is so even though hackers seem to be historically linked to amateur radio users, and a leading hacker is also a leader in amateur radio.[45] This is so even though the challenge of initiating new users and the problems of abusive use, interference, and breakdowns in operating standards and cooperation are similar in amateur radio and on the Internet. Nonetheless, government licensing of Internet users would be abhorred as a violation of God-given inalienable rights. Or abhorred as a violation of natural human rights. Or abhorred as a violation of what most persons, deliberating under appropriately specified circumstances, would come to agree to regard as rights persons should have irrespective of decisions made by duly constituted governing authorities. Freedom to use the Internet is not understood as a privilege granted by national governments and international treaties. In the Internet field, freedom means capabilities that persons should personally recognize, cultivate, and defend.
Internet users have recognized, cultivated and defended capabilities that some governments would prefer to suppress. Supporters of democracy in China and adherents of the Falun Gong movement have vigorously sought to communicate with persons in China. When the founder of Chinas first human-rights website was arrested, supporters copied his website to a server in the U.S. and the contents of the website remained accessible to persons in China.[46] In contrast to amateur radio communications, international law does not require the U.S. or any other country to shut down Internet communications that the Chinese government does not want to occur.
[tags]freedom, ham radio, spectrum management, spectrum policy, fcc[/tags]
My first contact into Mexico
On 14.032MHz, thank you, Arturo.
[tags]ham radio, dx[/tags]
Internet Field Day
Jeff Pulver was kind enough to allow me to help shape the discussion around his Internet Field Day idea.
For those who may not know, Jeff has for years led the public charge for the Internet generation to deploy voice over IP technologies, largely through his VON conferences. He’s also WA2BOT.
[tags]ham radio, emergency communications, jeff pulver, internet field day[/tags]
Jeff Pulver promotes Internet/amateur radio common ground
Jeff Pulver, WA2BOT, and Internet Voice over IP pioneer, suggests starting an Internet tradition akin to amateur radio Field Day. Jeff describes Internet Field Day “as an annual activity that would bring together members of the Internet Community who wish to become better skilled at Post-Disaster Communications together with a community of people who have a history of being active in the space, the worldwide ham radio community.”
Traditional amateur radio Field Day exists as a annual event to prepare and exercise portable communications systems for a day we hope never comes: natural or manmade disaster. Once a year as a community activity, hams pack up their gear and operate in the field for 24 hours under power off-the-grid. Practice makes perfect - systems and procedures undergo hardware- and bit-rot unless they are exercised and used. Jeff’s idea being that emergency ad-hoc Internet data networks, which obviously can also bear voice traffic, can participate in this off-the-grid drilling and field exercise.
Nice job, Jeff.
[tags]disaster communications, disaster preparedness, ham radio, emergency communications[/tags]
My first QRP contact
My thanks to John, WI6O, for being my very first CW QRP contact. John is in Moorpark, CA and I’m in Pasadena. Not a vast distance at 45mi, but good to be heard.
My power was 2 watts, using my kit-built NorCal40a on 7.020MHz. John was also running QRP at 5 watts with his Elecraft K1 (which I would also like to build).
The NorCal40A runs off 10 AA batteries, into a 70ft (1/2 wavelength at 40m) long wire as high up in the tree as I could get it. All this took place in my front yard tonight, and which proves I can do a portable Field Day with this rig and a thermos of hot coffee.
Thanks again, John!
[tags]ham radio, qrp[/tags]