Tuesday, December 27, 2011

DIY - ARRL and Radio Shack

Back in June of 2011, I pointed out that there is a resurgence in the Do-It-Your-Self (DIY) community.

The economic crisis, Make Magazine, and the development of Maker Faire's/ "Maker Fests", all have apart to do with this.

A while back Radio Shack asked the "DIY community" what they would like to see in Radio Shack stores.

The top ten improvements requested were:
1. Arduino
2. More Kits and Project Suggestions
3. More introduction/instructional books
4. Larger assortment in LEDs
5. Wider variety in resistors
6. TONS more capacitors
7. DIY audio and speaker equipment
8. HAM radio gear
9. More competitive pricing
10. Stronger sales force

Since that time, Radio Shack has added Velleman Kits, and Arduino Kits as well as other things.

The ARRL just launched a new DIY campaign.

As I and the ARRL have noted, DIY is certainly nothing new to ham radio. But there are tons of DIY people out there that do not know about ham radio.

This may shock you, but I applaud this ARRL effort. Their recently released video is worth a look:

Sunday, December 18, 2011

Mesh Potato

An interesting video was just posted on the TAPR YouTube channel. It's a presentation that David, VK5DGR gave at the 30th Annual ARRL and TAPR Digital Communications Conference. This was held back in September in Baltimore, Maryland.



In East Timore, there is no local phone service to speak of. Most people have cell phones, but they can't afford to use them. That costs 25 cents per minute, for people who earn about a buck and a half per day. That situation is duplicated in developing nations around the world.

Australian Amateur Radio Operator David Rowe VK5DGR is part of a group that's trying to change it. They've engineered a local phone system that's cheap to install and free to use. It's based on WiFi mesh networking, and it's being tested in South Africa and East Timore. They call it The Village Telco. And it's working.

David related the story of the Village Telco at the 2011 ARRL/TAPR Digital Communications Conference, at the Saturday Night Banquet. The DCC is an annual, three-day weekend conference covering digital communications in Amateur Radio....


http://villagetelco.org/

The Village Telco is an initiative to build low-cost community telephone network hardware and software that can be set up in minutes anywhere in the world. No mobile phone towers or land lines are required. The Village Telco uses the latest Open Source telephony software and low cost wireless mesh networking technology to deliver affordable telephony anywhere.

Mesh Potato – A low-cost wireless mesh device you can plug a regular phone into

The Mesh Potato is a combination of a low-cost wireless Access Point (AP) running mesh networking software with an Analog Telephony Adapter (ATA). Mesh Potatoes automatically connect with each other, forming a “cloud” of Mesh Potatoes. Each Mesh Potato relays the phone calls for other Mesh Potatoes, greatly extending the range of the network. Plug an ordinary telephone into one Mesh Potato and you can instantly make a phone call to any other Mesh Potato on the network.


Here's what a US ham has done with this mesh potato for emergency use:
http://villagetelco.org/2011/11/guest-post-adapting-mps-for-emergency-work/

Sunday, November 20, 2011

70cm DATV and the future




Here is an interesting excerpt from an articled titled "Earth-shaking ATV, Plus.." by N5EM in CQ-VHF Magazine, March 1999 that I recently ran into.


Digital ATV Is Heating Up!

Since I last wrote about some possibilities in Digital Ham TV (DHTV), several reports of experimentation have been received. As long as there are efforts to make digital ATV a reality , I'll report on the work and keep you informed. One of the best developments is the previously mentioned e-mail re-mailer for DHTV. Check out the Web address for information about reading and posting messages to this list.

For those of you who may not have yet experienced an e-mail list, it is the method of sharing information in the information age . By "subscribing" to the list, you become a recipient of any e-mail message that is sent to the list. Anytime a message is e-mailed to the list, it is re-mailed to every subscriber, all in a matter of minutes. It lets people share ideas and information on a near real-time basis with like-minded experimenters any where in the world.

There are e-mail re-mailers (also called "reflectors ") for virtually any subject the mind can conceive of. Some have only a handful of subscribers while others have literally hundreds of thousands . There are several good e-mail re-mailers for the ATV community. One place to find out about them is at the Houston Amateur Television Society's Web site located at .

Some work with DHTV this month comes from Les Rayburn , KT4OZ, and Tom Askew, KB5IHI. They've been experimenting with video transmission using IBM Wireless LAN PCMCIA cards operating on 2.4 GHz. In their tests, Les and Tom used two laptop computers and wireless LAN (local area network) cards, transmitting Real Media data streams approximately 800 feet and resulting in actual ATV QSOs. Quoting from their test report,

"At 28.8 kbps encoding, it was...possible to have two-way (full duplex) QSOs, but at 56 kbps encoding the stream broke often. The Wireless LAN cards have a rated bandwidth of 512kbps but much of this is taken up by the protocol functions .One-way QSOs were possible at virtually any encoding speed, and high quality video (P5) was exchanged out to our maximum distance."

Not bad for a couple of laptops and a pair of $30 LAN cards. These LAN cards use spread spec trum and are Part 15 devices (they don 't require a license when used without modification). Since Les and Tom plan to modify these cards with the addition of amplifiers and external antennas , they've decided to participate under the Special Temporary Authorization (STA) of the Tuscon Amateur Packet Radio organization (TAPR) that allows the use of the frequency- hopping method employed by the wireless LAN cards in the amateur band s. After having initial success using the Real Media streams, Les and Tom have transmitted MPEG1 streams at distances of up to three miles using the unmodified Part 15 devices. These streams have included pictures, callsigns, and voice in each test.

So, DHTV experimentation is alive and well in the U.S. Other amateurs are participating in the experimentation and discussion, including Clint Turner, KA7OEI, in Salt Lake City, Utah , and Woody Winstead , KJ4SO, in Raleigh, North Carolina. If this interests you, subscribe to the DHTV re-mailer and start learning about the future of ATV.

I don 't want to leave you with the impression that DHTV is something going on only in the U.S. Quite the contrary- digital ATV experimentation in Europe is several years ahead of us. As early as 1996, the Austrian ATV organization had proposed MPEG 1-based digital ATV as the new standard for the 70centimeter band. This was to try to reduce the constant pressure on spectrum-intensive modes like ATV in countries where the total 70-centimeter band is considerably smaller than what we enjoy in most of the U.S. If you would like to read this proposal, you can find it on the Internet at . It's a very enlightening concept.


Ten years or so later, and we sadly aren't much further.

TAPR recently created a DigtalATV yahoo group. From what I gather DATV is pretty popular in Europe. The problem is it will cost nearly $2,000 to do 1 watt QAM Digital or DVB-S.

Not to practical for a one way transmitter in my book. It has been said that Image communications were never intended to be a mode independent of phone.

With that said, and the early experiments using less expensive 802.11 gear to achieve the same, I'd like to re-introduce that idea.

For those not up to speed, a normal 802.11 signal is 20 MHz wide. This is not a problem on 900 MHz or above, since there is plenty of space and little crowding.

For those not aware, if you use Atheros chip based 802.11 gear, half rate (10 MHz wide), and quarter rate (5 MHz wide) options are available using open source drivers.

And even more interesting is that that within the Atheros chip it is possible for licensed developers to enable a local oscillator generation for a direct conversion radio transceiver. This is not an open function, but irregardless, this is how 802.11 products on 900 MHz (Ubiquiti XR9), and 3 GHz (XR3).

And now 420-450 MHz with a module designed by Doodle Labs.

This is perfect for this type of application, as well as a multitude of other amateur infrastructure applications.

You can read more on the history of ATV and HSMM here:
http://www.qsl.net/kb9mwr/projects/wireless/70cm-ATV-HSMM.html

And what other hams are doing with (muti-mode) 802.11 here:
http://kb9mwr.blogspot.com/search/label/80211use

Saturday, November 19, 2011

Library of AMBE-files

This has been on my to do list for a long time.

About this time last year, Kristoff ON1ARF wrote some excellent open source software.

You can find it here: http://villazeebries.krbonne.net/dstar/voice-announce/

From: http://villazeebries.krbonne.net/hamstuff/?page_id=10
Voice-announcement system on analog repeaters have existed for .. well .. almost forever. D-STAR repeaters, on the other hand, have so-far had this in a very limited way.

The main reason for this is related to the use of the AMBE voice-codec in D-STAR. AMBE-encoders are only available via an external hardware-device (either a chip inside the transceiver or the DVdongle). As this technology is usually not present in a D-STAR repeater, it has up-to-now only been possible to play out a fixed audio-message...

The “dstar voice-announce” package aims to provide additional ways to generate voice-announcement messages on a D-STAR repeater. It is designed to be as flexible as possible, to provide as much choice to the sysops.


By concatenating the .ambe files for “good morning”, “the time is now” “6″ “o’clock”, a complete voice-announcement can be created (also in .ambe format)

Kristoff created a small library of common words using the eSpeek text to speech synthesizer.

I'm not real fond of the voice quality of eSpeak, or Festival/Flite for that matter. So I created an alternate more extensive voice library. Mine contains about 360 words.

Now you don't need a DV Dongle to create system announcements. You just need to install and use Kristoff's ambestream program and download my or his AMBE word library.

You use it like so:

 ambestream -t TEST -v -4 -my KB9MWR -d w1abc.dstargateway.org -p 40000 K9EAM B this.ambe is.ambe a.ambe test.ambe  


Rather than having to specify the path to each ambe word, here is way to use sed to append the full path to the premade AMBE words. In this example I have all my words in /root/words/ambe

 #!/bin/bash  
 #SENTENCE="this.ambe is.ambe a.ambe test.ambe"  
 SENTENCE="this is a test"  
 #  
 # note all forward slashes must be escaped. Just follow the example  
 #  
 #SPEAK=`echo $SENTENCE | sed 's/[^ ][^ ]*/\/root\/words\/ambe\/&/g'`  
 SPEAK=`echo $SENTENCE | sed 's/[^ ][^ ]*/\/root\/words\/ambe\/&.ambe/g'`  
 #  
 #echo $SPEAK  
 ambestream -t TEST -v -4 -my KB9MWR -d w1abc.dstargateway.org -p 40000 K9EAM B $SPEAK  


Please note if you get an error "Error: could not create udp socket! Exiting!" with Kristoff's program, it would be because ipv6 is not installed or enabled. To correct that see:

http://wiki.centos.org/FAQ/CentOS5#head-47912ebdae3b5ac10ff76053ef057c366b421dc4

Friday, November 11, 2011

ARRL Committee Seeks Microwave Band Plan Input

I've blogged before on some ARRL microwave band-planning.

Well apparently they are now seeking input:


"An ARRL Ad Hoc Committee has been tasked by the Board of Directors with recommending updates to the ARRL band plans for the amateur bands between 902 MHz and 3.5 GHz. If you are now active on any of these bands or are developing plans to do so, the committee would like to hear from you."


You have till December 15th to respond.

http://www.arrl.org/news/arrl-committee-seeks-microwave-band-plan-input

Monday, October 31, 2011

CisarNet: Italian Cisar Radio Amateur WiFi Network

This just in from IW0SAB, Renzo in Italy:



The National Digital Link Cisar CisarNet (http://wifi.cisar.it), is an ambitious project that is joining much of the Italian region via a backbone digital technology wifi connections to 2.4 and 5.7 GHz, which allows experimentation for radio amateur and any use if needed in an emergency to coordinate and support relief efforts.


They have a 304 km (world record) link on 5.7 GHz. And other impressive wireless links back to other parts of the Hamnet that I have blogged on before.

They have an English wiki that is worth taking a look at.

On the top of this infrastructure, CISAR is activating several services, from voice and video over IP, DSTAR support and conferencing systems.

Thursday, October 20, 2011

802.11 Digital Audio Repeater Linking






Some time back I planted the idea of linking analog repeater together using 802.11/HSMM.

Instead of dedicated link channels usually on 440 MHz, you'd put some of that microwave spectrum to good use.

Since most repeaters are on commercial towers, achieving the required line of site and fresnel zone clearance shouldn't be a problem.

Each repeaters audio would be converted to VOIP using an Asterisk solution or now the plug and play CL-100 controller from CAT. (As seen above)

The advantage is now that is a multi-use link. There will be plenty of bandwidth left over for APRS i-gate traffic, Winlink, etc. Not only that, but other repeater linking could be done on the same 802.11/HSMM microwave backbone.

High speed Multi-Media interconnecting backbones can support radio linking of today as well as of the future.

Large regional and statewide linked repeater systems really should give this idea some consideration.

Thursday, October 13, 2011

Friday, September 30, 2011

White House Staff on Amateur Radio’s Capabilities During Emergencies

From: http://www.arrl.org/news/view/arrl-briefs-white-house-staff-on-amateur-radio-s-capabilities-during-emergencies

On September 12, at the invitation of White House Cybersecurity Coordinator Howard A. Schmidt, W7HAS, the ARRL briefed several members of the National Security Staff on the capabilities of the Amateur Radio Service to communicate in emergencies. “The White House is looking for ways that the great work of Amateur Radio operators can continue to support emergencies in the future with particular attention to increased use and dependency on internet based technologies,” Schmidt said. The ARRL presentation, conducted by Emergency Preparedness Manager Mike Corey, W5MPC -- along with President Kay Craigie, N3KN, and Chief Executive Officer David Sumner, K1ZZ -- focused on Amateur Radio’s current and evolving capabilities to provide Internet messaging connectivity.


Related:
http://kb9mwr.blogspot.com/2011/03/hsmm-420-430-mhz.html

http://qsl.net/kb9mwr/projects/wireless/70cm-ATV-HSMM.html

Sunday, September 4, 2011

New digital Yeasu Radio

During the last Tokyo Ham Fair, Yaesu presented a new line of digital ham radios.

The label placed on the glass case in front of the HT has "C4FM" and "FDMA" in English.

Vertex has been making and selling P25 commercial HTs for several years now. It's not such a stretch for them to come out with a dualband P25 radio under the Yaesu (amateur line) brand. Remember that they're now owned by Motorola.



There is also a new page on the Yeasu website titled "The Dawn of Digital Communications in the Amateur Radio World."


"2012 will be a historic year that sees Yaesu lead Amateur Radio into the modern era of Digital Communications."

Friday, September 2, 2011

DV Open Source Modem




Some German hams have developed a digital voice board capable of GMSK (DSTAR) and 4FSK (APCO25). It uses a DSP Encoder and Decoder.

The capabilities of their board are mostly defined from the firmware. It can handle baseband reception up to 8kHz (^=16kbaud, defined by the analog low pass filter).

Transmission is possible form DC up to 1/2 DAC update rate (a RC low-pass soften it). You can modulate on 2 DAC-channels simultaneously.

If someone want to write a firmware for an APCO, Analog, PacketRadio repeater - please let Jan, DO1FJN know.

For more info visit http://www.dvrptr.de/ And the corresponding yahoo group, DVRPTR.

>what type of programming adapter do you use?

http://www.atmel.no/beta_ware/

> Is the AVRISP-mkII useable ?

I'm not sure. If you mean the JTAGICE mkII: Yes.

You can use the (cheaper) AVR Dragon too. A complete list of hardware you will find on Atmels website (AVR 8/32 bit �C -> Tools).

> Is there a better one allowing debugging?

Yes and No (Jain). You can use a AVR ONE! This device supports more trace
capabilities.

> What version of AVR-Studio do you use?

AVR32 Studio 2.7beta but the last official 2.6 works too. We don't want use the
new 'AVR Studio 5' - it's a Windows only solution.

Monday, August 29, 2011

Deviation Meter

I hadn't built anything in a while. And a friend mentioned the desire to have something to check for proper deviation on various Echolink and repeater setups.

In a prior blog, Are you narrow or wide?, I covered more of the background.


There is a lot out there on this sort of thing.

http://www.repeater-builder.com/projects/poor-mans-dev-meter/devmeter.html


http://www.repeater-builder.com/rbtip/deviationmeter.html

https://archive.org/stream/73-magazine-1993-08/08_August_1993#page/n23/mode/2up

So I suggested we build this and hook it to a an old dedicated scanner. And after construction we calibrated it against a club IFR-1200 service monitor.

If you are not found of breadboarding, the above 73 article has an etched board available:

http://www.farcircuits.net/test1.htm

Here is a video that my friend made:

You'll be disappointed to know that Radio Shack doesn't carry the 15 vdc panel mount meter anymore.

Tuesday, August 23, 2011

LifeNet

A interesting Mesh like network was brought to my attention. It's called LifeNet.


In the wake of major disasters, the failure of existing communications infrastructure and the subsequent lack of an effective communication solution results in increased risk, inefficiencies, damage and casualties. Current options such as satellite communication are expensive and have limited functionality. A robust communication solution should be affordable, easy-to-deploy, require low-to-zero infrastructure, consume little power and facilitate Internet access.

LifeNet is a WiFi-based data communication solution designed for post-disaster scenarios. It is open-source software and designed to run on consumer devices such as laptops, smart-phones and wireless routers. LifeNet is an ad hoc networking platform over which critical software applications including chat, voice messaging, MIS systems, etc. can be easily deployed. LifeNet can grow incrementally, is robust to node failures and enables Internet sharing. A novel multi-path ad-hoc routing protocol present at its core, enables LifeNet to achieve these features.



LifeNet exploits multihop communication to provide coverage over comparable areas with minimal infrastructure. Every device functions both as a host and as a router. Two devices close to each other communicate with each other directly, whereas communication between two far off devices can be relayed by low-power intermediate nodes in a multihop fashion.


More can be read here.

Wednesday, August 10, 2011

Velleman VM100 / K8055 and the VM132 Temperature reading

More stuff with the Velleman VM100 / K8055 Experimental USB Interface

In the past we used this board for repeater activity logging:
http://kb9mwr.blogspot.com/2010/02/vellman-k8055-activity-graphs.html
http://www.qsl.net/kb9mwr/projects/voip/activity-graphs.html

Today we will use it to monitor temperatures.  The hookup is printed on the back of the VM132 cardboard packaging.  In case you misplaced that:





If you were to just connect a thermistor to the analog input of the USB interface board, you'd have to put a table to your program to convert the voltage to temperature. The voltage over the a NTC conduction model thermistor is very non-linear vs. temperature.  This table is essentially what is on with the TLV2741 comparator chip on the VM132 board.

The analog inputs of a K8055 are supposed to get an input voltage. With jumper SK2 open and ATT1 turned fully clockwise, that input voltage should be in the range of 0 to +5V.

The VM132 Universal Temperature Sensor has a 0 to 20mA current loop.  After the connections are made it is just a matter of adjusting the K8055 ATT1 and or the blue multi turn VM132 trim pot to calibrate the returned software reading to the actual temperature.


Velleman VM110 Experimantal USB Interface
Velleman VM132 Universal Temperature Sensor
+12 volts to the sensor

Linux k8055 library binary:  http://libk8055.sourceforge.net/

 Syntax : k8055 [-p:(number)] [-d:(value)] [-a1:(value)] [-a2:(value)]  
        [-num:(number) [-delay:(number)] [-dbt1:(value)]  
        [-dbt2:(value)] [-reset1] [-reset2] [-debug]  
     -p:(number)   Set board number  
     -d:(value)   Set digital output value (8 bits in decimal)  
     -a1:(value)   Set analog output 1 value (0-255)  
     -a2:(value)   Set analog output 2 value (0-255)  
     -num:(number)  Set number of measures  
     -delay:(number) Set delay between two measure (in msec)  
     -dbt1:(value)  Set debounce time for counter 1 (in msec)  
     -dbt2:(value)  Set debounce time for counter 2 (in msec)  
     -reset1     Reset counter 1  
     -reset2     Reset counter 2  
     -debug     Activate debug mode  
 Example : k8055 -p:1 -d:147 -a1:25 -a2:203  

What it returns looks like a string of 6 numbers, separated by semicolons.
 Example: 499;16;128;230;9;8  
        499 : Measure done 499 msec after program start  
        16 : Digital input value is 10000 (I5=1, all other are 0)  
        128 : Analog 1 input value is 128  
        230 : Analog 2 input value is 230  
        9  : Counter 1 value is 9  
        8  : Counter 2 value is 8  

So we need to create script to pool the k8055 program and look at that third number, analog input 1.
 #!/bin/bash  
 #  
 # Bash wrapper to watch the input of a Vellman K8055 board.  
 #  
 LAST=0  
 while true  
 do  
 T=`k8055 | awk -F ";" '{print $3}'`  
 #  
 if [ $T -ne "$LAST" ];  
   then echo `date '+%b %d %Y %T'`: TEMP $T  
 fi  
 LAST=`echo $T`  
 sleep 1  
 done  
-
 [root@kb9mwr k8055]# ./temp  
 Aug 02 2011 00:44:17: TEMP 66  

Monday, July 11, 2011

DUTCH*Star DV Node / WinDV








http://www.blogger.com/img/blank.gif
Fred van Kempen, PA4YBR has written a new Windows program for use with D-Star DVAPs, and GMSK node adapters. It also works with the (blue) DV Dongle, amongst other things.

The DV Node program, (WinDV) will eventually take over most of the "market" currently serviced by DVAR Hotspot, as DVAR has reached the end of its development cycle - the "takeover" by DV Node has been in direct discussion and agreement with Mark McGregor, KB9HKM.


The beauty of his WinDV program is that is supports a combination of several protocols.

DPlus (regular gateways and reflectors) as well as the DExtra protocol used by the Xreflector system. And the newly emerged DCS reflector system.

Also supported are D-STAR Callsign Routing (through ircDDB) and the reporting of GPS positions to the APRS network.

His program should enable more D-Star users to be able access both networks. As currently most D-Star repeaters in DVAP/Dongle users are only able to access the US Trust based network. Where as; homebrew GMSK nodes and repeaters as well as Dongle users using G4KLX Digital Voice package have had access to XRFxxx based reflectors.

Icom stacks/gateways can implement both ircddb and dextra (XRF) linking. I encourage all Icom gateway operators to consider widening the D-Star experience for their users.

I feel Win DV is a great step towards interoperability and hopefully exposing and migrating more users and gateways to a more open source based D-Star infrastructure.

In the future, Fred also notes he plans to develop a version for Linux, and Mac.

I encourage you to check out WinDV today!

Sunday, June 19, 2011

Innovating Makerspaces

Here is something that I wrote for my local ham radio club.

Ham radio operators have long been some of the original open source , Do-It-Yourself (DIY) proponents.

Going back in time, radio stuff was expensive and out of the reach of a lot of hams. So they invented newer and mostly cheaper ways of doing things. They also came up with better ways of doing things because somebody else would see that idea in print and improve upon it. Of course the technology was rather rudimentary, and there was little way to go but up at that point in radio technology calendar.

What most people tend not to think about is the open-source nature of Amateur Radio. While operators most often are seen working in emergency situations, many of the modern conveniences we have today—cell phones, satellites, wireless devices— were developed and tested by radio amateurs.

Decades ago, amateur radio operators were on the forefront of scores of technological innovations, including television, digital communications, solid-state design and cellular networks. The hobby's roots trace back to radio pioneers such as Guglielmo Marconi and FM-inventor Edwin Armstrong.

Well a lot has changed over the years in society and ham radio. Many amateurs have gotten away from these "do-it-yourself" roots. But those types are still out there!

When the economic crisis first started to unfold in 2009, the Wall Street Journal just had an article on how Tinkering is making a comeback amid the economic crisis.

"The American tradition of tinkering -- the spark for inventions from the telephone to the Apple computer -- is making a comeback, boosted by renewed interest in hands-on work amid the economic crisis and falling prices of high-tech tools and materials.

Engineering schools across the country report students are showing an enthusiasm for hands-on work that hasn't been seen in years. Workshops for people to share tools and ideas -- called "hackerspaces" -- are popping up all over the country; there are 124 hackerspaces in the U.S."


In 2005 just shortly before the economic mess stated to unfold, Make Magazine was introduced by O'Reilly Media. It focuses on do it yourself (DIY) and/or DIWO (Do It With Others) projects involving computers, electronics, robotics, metalworking, woodworking and other disciplines.

The magazine was well accepted by engineering and electronics students. And led to the first Maker Faire. An event filled with DIY projects, science, demos.

These "fests" are now in their 6th year, and being held in California, Detroit and New York and many other places.

As mentioned in the Wall Street Journal article, regional groups are popping up all over the place to help support this innovation. These are referred to as Makerspaces/ Hackerspaces. They are places where people with common interests, usually in science, technology, or arts can meet, socialize and collaborate. A Makerspace can be viewed as a community lab, machine shop, or workshop where people of diverse backgrounds can come together to share resources and knowledge to build/make things.

There are two that I know of in our area:

http://milwaukeemakerspace.org/

And closer to home, http://www.dhmn.net/ an Appleton: a group of hacker/maker/software/hardware technology-enamored people.

If you still have a bit of "amateur" in you, I encourage you to branch-out and check these innovative groups out. I think there can be / should be a lot of crossing over and sharing of talents between some ham radio folks and these groups. These are the types of people that need to welcomed with open arms into the hobby.

Saturday, June 18, 2011

CQ VHF Magazine Index



I announced about a week ago via twitter that I have been working on an article index for CQ-VHF Magazine. At thing point I believe it to be a complete article index since the magazine went quarterly in 2002.

As I explain in the index; "most of my interests lie on VHF above, and having acquired most of the issues since the publication went quarterly, the CQ VHF indexing became a new project."

You can view it here:

http://www.qsl.net/kb9mwr/files/ham/cq-vhf.html

I am missing issues when the magazine was monthly. If you have and are willing to sell any of the following issues, please contact me. Jan 1999, Jan 1997, Feb 1997, Nov 1997, And any from 1996.

Friday, May 27, 2011

More graphs

A couple years ago Will Payne, N4YWK was on a quest to graph some of the historic growth of repeaters.



I helped provide some of the data for him. But more recently I wanted to take a look at 70 centimeter ATV growth.



That of course lead to more counting as I wanted to look at the 900 MHz band in light of Alino's announcement that they intend to release a HT capable of 900 MHz. The DJ-G29T.

Link to the FCC OET Papers:
http://tinyurl.com/dj-g29t



I've been exploring 900 MHz since 2008.

I think it's one of the still steadily growing bands out there that can be a lot of fun.

I had no intentions of buying a new HT any time soon, but the DJ-G29T is certainly changing my mind on that. I have wanted a frequency agile radio with a VFO for 900 MHz for a long time. I believe Alinco will be the first ham manufacture of a 900 MHz HT.

Sunday, May 15, 2011

D-Star ircDDB

A couple years ago on the D-Star gateway mailing list, it was discussed that the Icom G2 software was not impressive.

A few pioneering D-Star programmers (Scott, KI4LKF, and Jonathan, G4KLX, Hans, DL5DI, and others) discovered that callsign routing updates were sometimes taking upto 2 hours. These same guys ran into programming road blocks that the closed nature of the Icom/USTRUST/K5TIT trust that led them to the development of open source alternatives.

Jonathan Naylor, G4KLX recently created some statistics on the size of the ircDDB network against the USROOT based network.



The first thing to note is that the ircDDB network is larger in terms of gateways than the USROOT network. In most countries the number of gateways on the ircDDB network is greater, sometimes significantly so. With the rapid increase in numbers on the ircDDB network these numbers will increase further.

I feel that one of the reasons for this is that the ircDDB network is open, and encourages experimentation and open source. This is in contrast to the USROOT network where opaque and undocumented protocols are in use, yet some still stick to the Icom G2 system, claiming that it is somehow superior! Would these people claim that installing commercial software is more in the amateur radio spirit than home brew and documented software?

Just as an aside, take a look at http://www.va3uv.com/Vulnerability.htm.

Please feel free to distribute copies of this e-mail to anywhere you like, as long as you keep the numbers in the table the same of course.

Jonathan G4KLX

Friday, April 8, 2011

While I'm away

These will be some of the things I'll be playing with this Spring and Summer.



Here are a pair of Ubiquiti XR-9's. We started to experiment with these towards the fall of last year. We have a HyperLink Technologies HA910I-APC 10 Watt (+40 dBm) amplifier that could be paired with it.
--

Here are some older things that we have messed with on 2.4 GHz. Ubiquiti Nanostations and Bullets and going back even a few more years the WRT54G. We have slowly been moving away from 2.4 GHz. Our experiences have been that there is to much stuff on the band, and to many trees!
--


Here are some antennas. The top two are Comtelco's for 70 cm, yielding 10 dBd. I hope to be putting these to use soon! Some 900 MHz yagi's. HyperLink yagi's yielding 13 dBi, and then some stuff from 2.4 GHz.
--

Here are two router stations just aching for some 400 MHz mini-pci boards to be put into them!

And on the narrow band digital front, we have already begun comparing D-Star, P25 and Mototrbo. It began a week ago after some discussion at our local radio club banquet.



http://www.youtube.com/watch?v=vdGr12Qiosc

http://www.youtube.com/watch?v=JRJXNpJmOvs

Monday, April 4, 2011

Blog Hiatus

About a year ago I eluded to discontinuing this blog.

I received some positive encouragement at the time to continue it.

That said, I feel the same way I did a year ago... (if not more disgusted with the lack of leadership)

"I really don't know if ham radio these days is worth the effort I put into it."

So I will be taking a break.

If anyone stumbles into anything interesting going on in the hobby I'd still appreciate an email bringing it to my attention.

73'
Steve, KB9MWR





Here is an interesting speech that ARRL President Kay Craigie, N3KN gave at AES Superfest in Milwaukee on 4/2/2011, titled "Do Something new in Ham Radio."

Unfortunately this is the first time Superfest that I have missed in a long time. Had I know that she was going to be there, I would have attended so that I could share some of my thoughts in person.

The premise of her speech is good. In coincides with my own logic. There is some irony however.

She mentions a phenomenon that occurs with some hams where they "Narrow their perspective down on Amateur Radio so tight..."

I'm sure ARRL staff and other can see me as one of those types since I blog on certain things over and over.

The double irony is the ARRL's own perspective seems to be narrowed pretty tight to HF and ARES, and Contesting. So that is why you'll never read about anything in those areas on my blog. You'll likely only read about stuff that you won't read in QST or on the ARRL web, as I have tried to fill that void.

Kay, if you want to encourage hams to try something new, how about relaxing a few more rules?

The recent petition- wavier regarding voice and data emissions is a good start.

Friday, April 1, 2011

Internet Pioneer Paul Baran, W3KAS (SK)



http://www.arrl.org/news/internet-pioneer-paul-baran-w3kas-sk

What I'll add that he mixed his radio interest in by helping found Merticom. A pioneering wireless Internet service that existed from 1995-2003, long before "3G" and wifi..

For more technical info on the Merticom Ricochet Radios you may want to have a look here: http://www.qsl.net/n9zia/metricom/index.html

Friday, March 25, 2011

Bi-directional Amplifier Design

Well it's been a while since I ripped on the ARRL. And since they are doing such a great job, you knew it wouldn't be long before you'd see something so non-professional (amateur) from me again.

from kb9mwr@q...
to w9gig@a...
cc n4qx@a..., n7hpr@t...
date Sun, Jan 16, 2011 at 9:52 PM
subject bi-directional amplifier design help

Hello,

I'd like to help encourage the development/documentation of a bi-directional amplifier for high-speed multi-media applications.

I was prompted when I read the ARRL Homebrew Challenge I said to myself, why encourage something that has already been done.

Since there are more non-part 15 overlapping channels on 3 GHz, 5 GHz and 900 MHz bands I would encourage it to be for either of those bands.

I haven't been able to make much head way in this myself due to a lack of access to the necessary development equipment.

In some of the open source development efforts that I have been part of, a bounty is often posted as a reward for something like this.

I'd like to take the same approach to this, as I am offering $40 to anyone who can document such a design in QEX or the like. I'd also like to suggest that anyone else interested in the development also consider a contribution to the bounty (aka up-the-ante).

The total bounty-pledges of course will help who ever steps forward in their design and development costs.

To clarify, I am not requesting production or kits, just someone who wants the challenge and has the know-how to create a working prototype and will openly document their design in QEX or some other publication.

Would it be possible to get a blurb in QEX magazine to spread the idea out to the more technical crowd?

Thanks,
Steve, KB9MWR


Yeah, you guessed it, zero replies to my request.

And now some commentary on the HR 607 bill that has provisions to auction off a portion of the 70cm band.

I did my part and wrote to my representatives. While it would be a shame to lose this band, the lower half of the band is Very inactive. Around here the only part used for the most-part is 440-450 MHz.

The current band-plan that caves out the lower portion of the band for ATV and isn't bringing any real traffic/ use either.

Seems a shame that we can't setup a decent wireless (emergency) network, other than this pathetic Winlink business. Heck if we can't do it, sounds like that is exactly what the proposed Department of Homeland Security First Responder network is.

Time to move forward, else I have little desire to continue to write letters to try and defend spectrum that will just sit idle as it has been. Use it or lose it..... maybe the ARRL, TAPR and other "leaders" will one day realize they need to step forward and suggest some new ideas for the hobby to help not only "protect" the spectrum, but put it to actual use.

What I am reading is "When All Else Fails" ... we will build our own wireless network. Possibly a wake up call for ham radio?

Saturday, March 12, 2011

Letter to my local club

To: The President of the Green Bay Mike and Key Club.

Hello, my name is Steve, call-sign: KB9MWR. I’ve been active with the hobby since 1996 at age 16. I have been a member of the Mike & Key Club off and on.

I’d like to share some thoughts and observations and make some suggestions in the summary.

Fourteen years ago the mailed newsletters and repeaters where vital communication links for ham to share news and ideas amongst themselves. Now we are connected in a variety of different ways and the hobby is less relevant to many.

The newsletters now are electronic and cost the club nothing to reproduce and distribute. In my opinion they can no longer be viewed as a membership benefit. They should be viewed as a promotional tool, posted and shared publicly to encourage /show club involvement and in the hobby in general.

The emphasis on maintaining multiple club repeaters seems silly. The usage isn’t nearly what it used to be.

Hams keep in touch a variety of different ways now. Keeping things on the air for the sake of it, isn’t spectrally efficient. It’s a detrimental mentality that will surely keep future ham developments from obtaining spectrum.

In my opinion the role of the amateur service as changed quite a bit. It was technologically on top and interested many when I entered the hobby.

Autopatch, packet and the like, all before cellphones and the internet and other social networking avenues.

This no longer seems to be the case. However, I feel it still serves a purpose to those who like to experiment and “learn how things work.” The true technicians and amateurs in my eyes.

Ponder how can the club reach out to those types of people. They seem most likely to help the hobby move forward in my opinion.

The banquet is just around the corner. I’d like to see the ham of the year nomination process refined a bit.

I think nominations should be on merits, and not the buddy system. I think a statement of reasons accompanying the nomination would help bring some value back to the award.

With a new year just around the corner, I’d like to see some defined goals for the year ahead as well as a explanation of the benefits of membership.

Lastly, I’d like to suggest the board conduct a member interest survey and solicit suggestions for future club direction and if warranted make updates to the clubs Purpose and Scope in the By-laws.

Thanks for taking the time to read this and ponder how we as a club can be more beneficial to our fellow amateurs.

Steve, KB9MWR


Einstein said "Insanity is doing things the same way but expecting a different result."

My guess is none of this will happen, but at least I can say I tried.

Tuesday, March 1, 2011

HSMM: 420-430 MHz







It has been a while since I wrote on the idea of HSMM on the 70cm, 420-450 MHz band.

There have been some recent threats to the band with the proposed HR 607 bill.

So my logic to protecting the spectrum available to us, is to try and make better use of what we have, instead of letting it sit idle.

So following that logic, most of the lower part of the 70 centimeter ham band has been fairly idle. This is known as the Amateur TV sub-band (420-430 MHz).

ATV - 421.250 Video - 425.750 Audio
ATV - 427.250 Video - 431.750 Audio
ATV - 434.000 Video - 438.500 Audio
ATV - 439.250 Video - 443.750 Audio

So far there seems to be a fair number of hams interested in 802.11 based networks. But one of the big hurdles is understanding and overcoming the line of site, and other wide-band microwave propagation issues.

I've pointed out that 3 GHz is a great band since you won't be sharing the space with all kinds of other Part 15 unlicensed devices that inevitably lead to a higher noise floors and headaches.

The concept of HSMM on the 70 cm band intrigues me and others greatly because of the non-line-of-site possibilities.

A normal 802.11 channel is 20 MHz wide, but I wrote before that this can be reduced to 5 MHz.

I recently received an email from Jay Parikh with Doodle Labs mentioning he stumbled into this blog and was impressed by it.

He also wrote to bring my attention to a new product introduced by his company that would likely be of interest to the ham community.

Jay, mentions that they have already received a number of inquires from hams on it.

It appears Doodle Labs may be the first to consider offering a true non-line-of-site solution, capable of operation in the 70cm band that could easily fit into unused ATV channels between 420-430 MHz.



Doodle Labs has a new product which should be of interest to any amateur radio operator wishing to experiment with higher-speed digital data in the 70 cm UHF band. The Doodle Labs DL435 420-450 MHz OFDM Transceiver provides high-speed data in channel widths of either 5 or 10 MHz throughout the 70 cm amateur radio band.

The DL435-30 transceiver has a standard 32 bit, 33 MHz miniPCI interface and works perfectly with a Ubiquiti RouterStation. The RouterStation itself is powered via a standard power-over-Ethernet adapter. Note that the DL435-30 does have a fairly high current draw (around 2 amps) when run at http://www.blogger.com/img/blank.giffull RF output power.

The Ubiquit RouterStation or RouterStation Pro can be running either DD-WRT or OpenWrt. Note that currently OpenWrt doesn't allow manual selection of with channel width, so you may wish to try DD-WRT first.

The DL435-30 transceiver is based around the Qualcomm Atheros AR5414A baseband processer and a RF Micro Devices VCO and mixer. The DL435-30 transceiver itself "looks" like a standard 2.4 GHz 802.11g device in software, but the hardware is configured to provide a frequency offset of 2019.5 MHz. For example, if you select "2.442 MHz" in your configuration software the actual operating frequency will be at 422.5 MHz.

There are two channel widths available, 5 and 10 MHz, which are currently only manually selectable using DD-WRT and not OpenWrt. The 5 MHz channel width allows between 1.5-13.5 Mbps and the 10 MHz channel width allows for 3-27 Mbps. The modulation is Orthogonal Frequency-Division Multiplexing (OFDM) with 64 QAM, 16 QAM, QPSK, or BPSK depending on the received power level. The minimum sensitivity is around -97 dBm (for 1 Mbps). "Real-world" throughputs are around 7 Mbps for the 5 MHz channel width and 14 Mbps for the 10 MHz channel width.

Transmit power offset is an additional +10 dBm. So selecting +13 dBm (20 mW) in your software configuration would give a final tx output power of +23 dBm (200 mW). The DL435-30 has an option for using diversity antennas, with one MMCX jack for the main antenna and one MMCX for the auxiliary antenna.

With a 1989.5 MHz frequency offset, a proposed channel plan from Doodle Labs is below.

For 5 MHz BW, Center Freq. = 422.5, 427.5, 432.5 , 437.5, 442.5, 447.5 (For US and AU)
432.5 , 437.5, 442.5, 447.5 (For Canada)
432.5 , 437.5 (For Europe)

For 10 MHz BW, Center Freq. = 427.5, 432.5 , 437.5, 442.5 (For US and AU)
437.5, 442.5 (For Canada)
None (For Europe)

For 20 MHz BW, Center Freq. = 432.5 , 437.5 (For US and AU)
None (For Canada)
None (For Europe)



However, Doodle Lab's normal business model is to work with OEMs. Doodle Labs is not set up to address small quantity purchases. They are also concerned that they may get buried with the support questions. Doodle Labs has approached a few resellers to see if they can do this. But they want to see the demand first before they carry the product. So this is like a chicken and an egg situation.

Sore that reason, I've held off blogging about this exciting new development for some time, but with some limited communications with both Xagyl and Doodle Labs it appears they are at least curious about what kind of amateur market there is. Or at the very least are okay with some inquiries.

{Update 3/20/11}
After a bunch of discussion, Doodle Labs mentioned they planned on releasing a model that specifically covers the ham spectrum. (see below)

So at this point, they are still trying on getting a distributor lined up, and will be in touch with me and others who have contacted them as soon as that is done in approximately two months.

He notes the delay is actually on their side. There are some minor changes that need to be made to the design and their design team is completely swamped at the moment with a few different customer projects.

{Update 6/13/11}
Pre-Production stage. Expected availability is the end of October 2011.

10/11:
http://doodlelabs.com/products-and-services/amateur-bands/420-450-mhz-band-dl435.html

Now if we can just find a OEM interested in selling this. Till then, Doodle Labs will sell factory direct.


Sept 2012:



At the September 2012 DCC in Atlanta, GA, David Bern, W2LNX presented a paper titled  "Experimenting with High Speed Wireless Networking in the 420 MHz Band."


His paper reports on testing two different manufactures of 802.11 mini-PCI cards capable of operation in the 70 cm ATV sub-band using 5 MHz bandwith.

Test applications were a Webcam video streaming program and a file download server program that ran on inexpensive netbook computers.

The test documented in his paper prove a sustainable data rate of  1 Mbit/s over 10 miles.
 


Tuesday, February 22, 2011

Vint Cerf: "Re-Thinking the Internet"

Vint Cerf is recognized as one of the fathers of the internet. (He was a program manager for the U.S. D.A.R.P.A.) He was recently invited back to Stanford where he graduated, to give a speech to future engineering students.

There is a lot of interesting history and things to get you thinking in his presentation.


Pay attention to the end of the presentation for this:

Wireless was absolutely a part of the internet architecture.

I'm uncomfortable with the idea that the emergency network is dependent on a system that is often know not to work during emergencies.

Or If the emergency occurs in an area where there isn't any cellular infrastructure. (Base-stations, back haul)

So I actually like the idea of doing down a different path.

Which is a mesh like thing, that can be ad-hoc.

I also rather like the idea that everything transported in that system is IP based. The part that I like is, it doesn't care how its carried, it doesn't know what its carrying. It could be voice, it could be video, the network is oblivious.

By the way the police and fire departments and EMS today have a lot of trouble communicating. Because their radios have to work at RF. If Instead if we said the whole base is IP.

And if you need to communicate by voice we will use VOIP. And if we have to we will do RF transformations in some portable nodes.

The whole idea is that your compatibility on an end to end to based on VOIP, and not on radio compatibility. We'd have a much more general architecture.

For some reason that unknown reason that obvious fact has been resisted or ignored by the public safety environment.

Wednesday, February 2, 2011

No Internet, no problem?

PC World has a good article in response to the Egypt situation.

Does your government have an Internet kill-switch? Read our guide to Guerrilla Networking and be prepared for when the lines get cut.


Hams should give it a read as they are talking about Do-It-Yourself Internet With Ad-Hoc Wi-Fi / Mesh Networks.

The guys over at Noisebridge were the first to point out that another good reason hams should be building mesh networks is because of proposed internet kill switch bill.

Simultaneously, the United States is debating a bill to create an Internet kill switch, also known as the PCNAA bill. For true redundancy, a non-critical network can and should be built by the amateur service to avoid this single point of failure.


Some 10-20 years ago there were many private networks for automated teller machines, telephone, merchant credit card verification and so forth. Now most of this all happens over the internet. If there were some sort of major internet outage or attack, many day-to-day things would be interrupted.

Simply put, I'm pretty sure there would be major commerce and stock market effects. I have a hard time fathoming what would constitute a national cyber emergency, that would be worth those kind of side effects.

At the same time many ham radio systems use the internet for wormhole-like connectivity. APRS, WinLink, D-Star, IRLP, Echolink and so forth. An emphasis on building our own backbone and infrastructure is just simply not there. This leaves vulnerabilities in our emergency communications reliability.

There are some unknown vulnerabilities in the upcoming switch to IPV6, such as distributed denial of service attacks on IPv4 to IPv6 gateways. As well as root nameservers, and core internet routing.

The need for Speed and Digital Networks

Nearly 10 years ago a survey conducted by the ARRL Technology Task Force, of League members and other amateurs revealed that the number one interest in new technologies was in high-speed digital networks. Amateur radio, particularly EmComm (this was just after 911), needed some means of data transmission significantly faster than conventional packet radio.

Winlink is severely limited in capabilities and doesn't necessarily even conform to Internet Engineering Task Force (IETF) standards. As the population in urban cities grows so does communications. Have you ever thought how long it would take to covey even just 300 messages that loved ones are okay over such an antiquated medium?

If you still need more reasons to explore these wide-band modes, consider the fact that 99% of available amateur allocations go virtually unused.

Tuesday, February 1, 2011

Be a Life-Long Learner



From the Acknowledgments and Dedication page of the ARRL PIC Programming for Beginners Book by Mark Spencer, WA8SME:

I would like to acknowledge the contribution of you, the reader of this text.

As a life-long learner, you are my real inspiration. At times it feels like technology is passing us by, but I am inspired by those who want to be more than just technology users... and I thank you for that.


I've always been more interested in the experimental/technical side of ham radio, as opposed to the operational side.

And I have to agree with Mark. Those who truly inspire and make a difference in this hobby are those driven to learn.

The way I see it, primary interests of say; emergency communications, DX, contesting, Field Day, and QSO Party's are less constructive in the grand scheme of things.

Now I understand why over the years I have been slowly shifting away from the more traditional ham traditions toward the more experimental, futuristic ones.

How do you spend your time in this great hobby? (By the way, above are thumb nails of some books I have read and recommend)




Also worth mention is the OP-ED in the February QST by Randy Ross, KI4ZJI titled "Evolve or Die" makes good points. He points out the close tie between Amateur Radio and societies evolving technology. And to ensure that continues he suggests:

"Knowledge of computers and the Internet should be embraced and incorporated into the newest evolutions of Amateur Radio."

Thursday, January 27, 2011

New D-Star Developments



Above is a D-Star Support Matrix document that Scott, NS7C compiled. It's a good overview of what works with what.

"With all the various hardware and software options available, I sometimes forget which hardware works with which software."



Just before Christmas I asked on the dstar_digital group about decoding D-Star DTMF. I have found that is way to clumsy to have to handle all control functions using the URCALL fields. (especially when mobile)

About a year ago I had played with trying to decode it. I saw patterns, but wasn't able to define them, and had read that it might not ever be possible to use DTMF on D-Star as some thought it was implemented incorrectly by Icom.

Just after Christmas, Michael, DL1BFF proved this wrong. Turns out after cooking up some code to handle the bit interleaving and FEC processing, the DTMF is there just like the manual says.

To compliment this, Kristoff, ON1ARF has been working on some voice-announcement software.

This includes a wav2ambe tool, that uses a DV-dongle to encode multiple files in sequence to produce one single .dvtool or .ambe file. (useful to generate an announcement "on the fly" based on a sequence of wav-files).

As well as a wavstream tool to stream multiple wav-files in sequence. And ambe2wav - a new tool that can decode one or more AMBE-encoded audio-file (.dvtool or .ambe format) back into a wav-file.

He is also working on generating a predefined AMBE word / letter pack. This will enable D-Star repeaters to be able to concatenate words for announcements without the need for a DV-Dongle attached.

With these two tools, you will be able to setup scripts to speak weather reports and the like, just as hams have done with IRLP.

Also think of custom greetings and queries.

"Welcome Steve to the N9DKH D-Star repeater, the temperate is 67 degrees.".. when you make your first transmission after being idle.

You should also be able to query over the air when your friend was last heard, as well as just about anything else you can think of.

Scott, KI4LKF is still at it. His latest was working in D-Star voice mail.

YRCALL=_ _ _ _ _ _ S0
The above command will Store/create voice mail in the dvtool file x_voicemail.dat
YRCALL=_ _ _ _ _ _ R0
The above command will Recall/playback voice mail from the dvtool file x_voicemail.dat
YRCALL=_ _ _ _ _ _ C0
The above command will Clear/delete voice mail. File x_voicemail.dat will be deleted.
In all cases, the letter x in the file name x_voicemail is the module A,B or C


All very interesting ham developments worth checking out.

Intellectual Property

If you know me or have been reading my blog long enough, you know that I am a proponent of open source concepts.

I remember posting to the Texas A&M Mailing list back in 2007 because I was running into a glut of roadblocks related to Intellectual Property in various projects that I was dabbling with at the time.

"Leaders in the ham radio arena who are to busy beating their own chests touting things like they are the "national association for amateur radio."

These so called leaders need to suggest/ lay some general concepts to steer the hobby to the future.... focus on spreading the importance of the open source concepts in the ham radio arena"


In my last big project the 73 Magazine Index, I realized that its contents will become lost to posterity due to intellectual property issues. A dirty shame....

Interestingly enough, I have noticed that TAPR has grasped the open concept.

They came up with an Open Hardware License, and I just noticed that the DCC DVD I bought was licensed as a Creative Commons 3.0 Share-A-Like work.

Consider this:
TAPR's membership journal publication, the Packet Status Register (PSR) featuring both technical and non-technical articles is an authoritative source for up-to-date user and technical information on digital issues.

Explicit permission is granted to reproduce any materials appearing herein for non-commercial amateur publications provided credit is given to both the author and TAPR...


Yet I just noticed on the front page of the ARRL's site:
Copyright © 2010 American Radio Relay League. Reproduction of material from any ARRL Web page without written permission is strictly prohibited.
Also: http://www.arrl.org/copyright-faqs

I've also noticed that "ARES" is registered trademark of the ARRL and so forth.

I'm sorry if I have not properly denoted all these various trademarks. It's not intentional, it's just an encumberment that I don't have time to keep up with.

The reason I decided to blog about "Intellectual Property" is because my local ham club is in a potential law suit over IP use that could effectively flush this non-profit educational organization of all it's assets.

So I encourage you to think about all this, and how productive or non-productive intellectual property is to the hobby and the world.

Here are some of my favorites:

Revolution OS

The Code Linux

Pirates of Silicon Valley (you can't watch this online due to IP, but it's worth watching)

http://www.fsf.org/

http://www.gnu.org/licenses/gpl.html

Sunday, January 2, 2011

Understanding Digital

Okay so maybe the last couple microwave projects that I posted were not your bag.

There have been a few good videos from Hak5 lately.

If you aren't familiar, Hak5 is a weekly "home-grown" video podcast about computers, and technology.

I highly recommend it, and since someone left blog comments about the concept of more video content, well here you go.

If you are an old-timer, and videos on the web are too hip for you, I expect you to read Make Magazine.

A couple weeks ago the Hak5 crew covered Pulse Code Modulation. And the following week, Time Division Multiplexing (TDMA).

Both concepts in the show are used in relation to the telephone network. But they are both critical concepts to the basis of digital communications. (i.e. non-cw and other archaic forms of communication.)

As an example of how this ties in, I've been playing with Mototrbo, which happens to be a two-time-slot digital TDMA two way radio technology.

Remember: I'm trying to help hams expand their understanding and explore new ideas with my blog.

I can't be successful unless You spend time less time drooling (like full-fledged ARES member with down-syndrome) and ogling that utterly useless QST magazine.

Read something that will help your brain, and the hobby! I'll send you issues of 73 if I have to!

Saturday, January 1, 2011

Mad Scientist

I was happy to see DIY (Do it Yourself) on the cover of the January QST again.

I found the directional coupler - power/SWR meter article interesting, yet disappointing as it is only for HF.

The OP-ED member view point from Eric, KL7AJ titled "Put the Mad Scientist Back Into Ham Radio" reflects my own view point very much.

Eric points out the difference between his generation of Amateur Radio experimenters and today's batch of obsessed appliance operators.

"In our day, it was our job to create emergencies. The new EmComm oriented hams are intent on fixing emergencies."

He's referring to setting accidental fires building Tesla Coils, or Jacob's ladders, and things of this nature.

He makes a good point. If we want young blood in the hobby, we have to compete with paintball, bungee jumping and extreme skateboarding.

I highly recommend giving his opinions a read on page 82.

If you are ready, here is a nice experimental project from my Mad Scientist friend.

You know you are ready for the accidental RF burn from this 100 watt 2 GHz amplifier.