New Thing! Video!

I’ve been playing with antenna modeling, and decided to make a video series introducing this to other people who may be interested.

I’m new to this, but I think it came out pretty well. I only misspoke a couple of times, but it will probably only be noticed by the technical pedants (I count myself among these).

The first episode covers the basic user interface and some basic concepts. I already have plans to make more episodes, possibly with these topics:

• Basic data input file format for xnec2c
• Antenna tuning, resonance
• Single band beam antennas, more elements for more directivity
• The dB (Decibel) – as a unit AND a referenced quantity
• SWR – what it is, why it matters, and when it doesn’t
• How antenna height affects gain and impedance
• How to model traps in xnec2c
• Near field analysis – why do you need it and what does it mean?

I need to figure out where to place show notes for these, as there are a lot of good information sources about these topics on the internet already, and I need to reference those in each episode. I’ll get smoother at all that.

For the first episode, here’s how you can fetch the example files:

git clone git@github.com:sconklin/Antenna-Modeling.git

Here’s a link to my show page on blip.tv

And here’s the embedded episode:

I was jotting some notes for a future wiki page about how to debug network connections to dx clusters, and for my examples, I decided to use the host name dxspots.com.

and I ran across this:

sconklin@xps-1:/src/ubuntu$ whois dxspots.com

[ snip ] – some stuff removed

Registrant:
Ron Stordahl
701 Brooks Ave So
Thief River Falls, Minnesota 56701
United States

Registered through: GoDaddy.com, Inc. (http://www.godaddy.com)
Domain Name: DXSPOTS.COM
Created on: 20-Nov-01
Expires on: 01-Jan-13
Last Updated on: 04-Oct-10

Administrative Contact:
Stordahl, Ron xxxxxxxxxxxx@xxxxx.com
701 Brooks Ave So
Thief River Falls, Minnesota 56701
United States
+1.2186817900 Fax — +1.2186817901

Technical Contact:
Stordahl, Ron xxxxxxxxxxxx@xxxxx.com
701 Brooks Ave So
Thief River Falls, Minnesota 56701
United States
+1.2186817900 Fax — +1.2186817901

Domain servers in listed order:
NS2.DXSPOTS.COM
NS1.DXSPOTS.COM
NS2.ONVOY.NET

Interesting. Almost any hardware hacker recognizes Thief River Falls as the home of Digi-Key, in the same way as one might hear a bell when someone mentions Benton Harbor.

Looking a little deeper:

sconklin@xps-1:/src/ubuntu$ nslookup dxspots.com
Server: 172.31.0.1
Address: 172.31.0.1#53

Non-authoritative answer:
Name: dxspots.com
Address: 204.221.76.52

sconklin@xps-1:/src/ubuntu$ whois 204.221.76.52
#
# Query terms are ambiguous. The query is assumed to be:
# “n 204.221.76.52″
#
# Use “?” to get help.
#

#
# The following results may also be obtained via:
# http://whois.arin.net/rest/nets;q=204.221.76.52?showDetails=true&showARIN=false
#

Digi-Key Corporation DIGIKEY1 (NET-204-221-76-0-1) 204.221.76.0 – 204.221.77.255
Onvoy ZAYO-204-220-0-0-15 (NET-204-220-0-0-1) 204.220.0.0 – 204.221.255.255

#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/whois_tou.html
#

Ooooh, Digi-Key is actually hosting the dx cluster. Cool!

Final discovery? The registrant of the domain is Ron Stordahl, the founder and CEO of Digi-Key. Read the history for your self.

Nice! Thanks, Ron.

In a previous post, I covered a bunch of ways in which you can prepare to be useful after a disaster. If you’re interested in helping as a radio amateur, or you’re already a ham and want to get more involved in emergency communications (EmComm), then here are some additional things you can do to prepare and to be available as a resource when needed.

Get licensed

If you’re not already a licensed amateur radio operator, go ahead and get your license. See information in my previous post about how to do that.

Join the American Radio Relay League and participate in ARES

The American Radio Relay League (ARRL) is the primary organization in the U.S. for advocacy and lobbying on behalf of amateur radio. They provide publications, training, and many other services, as well as ARES, Amateur Radio Emergency Services. In many areas including here in Madison county, AL, it is through the ARES organization that the Emergency Management Agency makes use of amateur radio resources when needed. Using this list of ARRL sections, contact your section Emergency Coordinator, and ask them how to get more involved.

Take ARRL EmComm courses on line

Online courses offered by the ARRL are a great resource. They aren’t free, but the cost is reasonable for the value you will receive. Start with the EC-001 course. Prerequisites include some of the free FEMA courses mentioned in my previous posting.

Participate in RACES if available

In many parts of the country, Radio Amateur Civil Emergency Service (RACES) is a protocol under which local emergency management agencies make use of amateur radio operators to provide communications services when needed. In Madison County, we operate ARES and RACES as a joint organization, with very good results. Your local, county, or state Emergency Management Agency (EMA) may be able to provide more information about opportunities in your area, or you can get more information from other local hams, which brings me to my next suggestion:

Join your local amateur radio club

The quality and nature of local amateur radio clubs varies widely. Some are simply social gatherings, others provide technical programs for education of members, and some are highly involved in public service and emergency communications. We’re very fortunate in our area to have the Huntsville Amateur Radio Club (HARC), an active club, as well as a DX club that has a very technical orientation. Try your local clubs, and even if they don’t seem like what you’re looking for, ask people for suggestions – asking “I’m interested in emergency communications, who should I talk to around here?” may get you to the right people or club.

Ask questions

Keep asking questions like the one above. You can call the local Red Cross chapter and ask the person who does disaster assistance there which organizations in the area provide emergency communications. Ask people on your local amateur radio repeater. Listen for the times when local training nets are conducted, and announcements of local meetings. Check into the net, and feel free to ask for more information if they haven’t provided the information you need.

Find out who maintains your local repeaters and support them

There are a lot of factors that go into being ready to mount an effective response during and after a disaster, and infrastructure is a really important one. Amateur radio repeaters are a very important asset, and it’s easy to forget them when they’re not needed. However, good maintenance and continuous support means that they will be ready when needed. In my area, a number of repeaters are jointly supported through the North Alabama Repeater Association (web site is out of date), which funds repeater maintenance through memberships. We make it easy for people to support NARA by conducting a joint membership renewal drive each year with a single form for the Huntsville Amateur Radio Club, NARA, the Amateur Television club, and the packet radio club. We also have a dedicated group of hams who handle the maintenance tasks for the repeaters.

Participate in the practice nets and drills

Check in to your local nets, and participate in drills and Simulated Emergency Tests (SETs). Volunteer to be net control for training nets. All this builds skill and verifies that your equipment works but more importantly, it helps you build the social connections you need to know who is who within the local disaster response community.

Go to Field Day

Every year, ARRL sponsors Field Day on the fourth full weekend in June. This year it’s on June 25th and 26th. This is a good chance to meet amateur radio operators, many of whom will already be involved in emergency communications. Most Field Day sites have a “Get On The Air” station set up for new hams and non-hams to have an opportunity to talk on the air under the supervision of a licensed radio amateur. If you are already licensed for HF, try working a station – the skills you gain working a pileup of stations calling you is great experience. Hint: if you show up around lunch time on Saturday, a lot of Field Day sites will have a bunch of hams hanging around during lunch, and you can meet people and ask questions. To locate a Field Day site near you, try this online locator.

Go to Hamfests

Attending hamfests is a great chance to learn new things, especially at the hamfests which offer technical forums including topics on emergency communications. Like Field Day, you can meet other people with similar skills and interests, and hear stories about what worked and didn’t work during past disasters. See if you can find one near you.

Work DX, and try some contests

There’s skill involved in being a good radio operator, juggling technical management of your equipment with information transfer, and in training your brain to hear useful signals among noise. The more you are on the air, the better those skills get. If you have a license that grants you use of the High Frequency (HF) bands, then working distant (DX) stations is good experience. So is working contests, even if you aren’t equipped or motivated to be a serious competitor. Trying to keep up with the pace of a contest while operating your equipment and accurately recording information will build the same skills you’ll need in the middle of a disaster when multiple stations are calling, events are breaking fast, and you need to keep up.

Participate in public service events (marathons, bike races, etc)

This is good chance to meet other people active in your area, learn about repeater coverage in different areas near where you live, and compare the effectiveness of different pieces of equipment. You’ll also probably get to know the people who are active in emergency communications in your area, and will already know them before you’re needed in an emergency. Public service also builds awareness within the community, and demonstrates capabilities and professionalism to other organizations with which you may work during and after disasters.

Get some operating time in each of the radio rooms you may need to work in

If there are stations or radio rooms set up locally, get familiar with them in advance. For example, we have stations locally at the Emergency Operations Center, the American Red Cross, and at several area hospitals. See if you can visit and operate these stations. Find out which frequencies and nets they participate in during training, and learn their call signs. See whether they need operators present during Simulated Emergency Tests, and volunteer to get trained on their equipment. If they have HF capability and you can operate on HF, see whether you can use the station during a contest or on field day, or for a state QSO party. Being trained on all these locations improves your ability to help, and helps insure that any problems with those stations are spotted early, before an actual emergency.

Meet your ARRL officers

If you are an ARES member or want to be, then introduce yourself to your ARRL officers and get to know your Emergency Coordinator (EC) and assistant ECs. Many areas do not have an active ARES or RACES organization, and local emergency management officials may even be hostile toward volunteer hams. Sometimes this is due to past history, and sometimes due to a lack of understanding for what a good volunteer organization can bring to the table. In this case it may be difficult, and you may be the one who pioneers your local organization. Your best approach is to organize and train, and continue to demonstrate a high level of usefulness and professionalism. Eventually, your value will be obvious.

Starting from Scratch

If there isn’t an active emergency communications organization where you are, volunteer to start one, and contact the ARES ECs in neighboring counties and ask for help. It can take a long time to establish very close working relationships with Emergency Management Agencies. The effective collaboration that we enjoy between ARES/RACES and the EMA here in Madison County is due to years of very hard work, a lot of it by a handful of very dedicated people.

Summing it up

There’s a lot listed here. You don’t have to do all of it, or even much of it, to be useful in your community. After the tornado disaster here on May 27th, many hams participated who only had a mobile or handheld radio, and who had EmComm training and were not members of our ARES/RACES groups. Almost anyone who was available was able to contribute. But – if you want to maximize your effectiveness and the contribution you can make, then participation will help you achieve that. I haven’t mentioned equipment at all. It does cost money to establish a highly capable station, but the entry level equipment is not too expensive and to me, is worth the additional safety and peace of mind it brings to my family, even without my abilities to perform public service. It doesn’t matter what equipment you have if you don’t have the skills to operate it and understand how you can help during an emergency.

There’s a fundamental fact about disasters and disaster recovery that I try to explain every chance I get.

Here it is again:

The roles that can be filled by untrained volunteers during and after a disaster are very limited. Walk-up volunteers are generally limited to performing manual labor type tasks, and unable to do any real work until days after the disaster. There can be a need for this sort of spontaneous volunteer, but often there is not. After the recent tornadoes here it took thousands of volunteers to begin clearing trees and covering damaged houses.

Other efforts to help are often ineffective, or even counter-productive. Collecting old clothes, shoes, etc is easy for people to do, but the tasks of collecting, sorting, transporting, and matching these items to recipients are often impossible to complete in an effective and timely manner.

But – there are ways to contribute your specific skills to disaster recovery, no matter what they are. After a disaster, there is an almost immediate need for volunteers trained in specific areas important to recovery. These volunteers aren’t first responders, and often don’t even enter the areas of greatest damage (following a natural disaster). They’re critical to the efforts to get food, clothing, medical care and shelter to affected people. You can be one of those volunteers, but you have to be trained first. Right now is a good time to get started.

There are many agencies who participate in disaster recovery. My perspective is as a Red Cross volunteer and as an amateur radio operator in the United States, but there are equivalent agencies in many countries.

Some U.S. organizations I am familiar with are Southern Baptist Disaster Relief, the Salvation Army, and The American Red Cross. Each of these organizations needs people with all sorts of skills. Feeding, Sheltering, and caring for people involves cooking, bookkeeping, inventory control, logistics, communications, computer administration, damage assessment, public speaking, counseling, child care, pet care, and more.

If you are interested, sign up today so you can be ready next time. You can call your local Red Cross office about signing up to help with Disaster Services (or in other areas), or see whether your church or other group has an affiliation with disaster relief. Most agencies are understanding about the demands of family and work, so assignments are always voluntary and you generally don’t have to make a firm commitment to be “on call” unless you have a leadership role in the organization. Additionally, a lot of employers are generous about allowing their employees to help with disaster recovery. My employer, Canonical Inc, was very supportive after the tornado disaster here.

But there are other things you can do to prepare – not just to help on a large scale but also to help your family.

Here are some:

Get an amateur radio license and a radio

Getting your entry level license is not hard, and it can save your life or that of someone near you. During our recent five-day power outage, cell phones were not working for many people, and amateur radio provided a lifeline in at least two cases. In the first, a ham operator with a history of heart problems experienced symptoms of a heart attack, and was able to summon help for himself. In the second, a ham operator witnessed a neighbor who collapsed on his front porch. Although the area they were in had no cell or conventional phone service, he was able to call for emergency medical services and obtain treatment for the serious stroke that his neighbor was having. An added advantage in our area is the ability to follow storm spotter reports live, instead of sometimes waiting critical seconds or minutes for them to make it through the pipeline to Radio and TV (to the great credit of the National Weather Service and the media, it really is usually only tens of seconds before a report of a tornado results in an official warning)

There are a lot of resources available to help you get your license. This web page is a decent starting place. There are books available to help, including ones published by the ARRL and ones by Gordon West, and many amateur radio clubs offer classes. I recommend checking out the local club. You may find a really nice group of mentors.

The test for the entry-level (Technician) license is 35 multiple-choice questions, randomly selected from a pool of almost 400 questions. Many of these questions are similar, and the entire pool is publicly available, so you will never see a question on the exam that you have not had a chance to study.

In the U.S., license exams are administered by other hams, Volunteer Examiners. In most places, the fee to take the exam is about $15.

If you want to contribute to emergency communications and disaster recovery as an amateur radio operator, there are a lot more opportunities to train and participate, which I’ll cover in more depth in another post.

Get free SKYWARN training

The National Weather Service offers free SKYWARN training, and it’s several hours very well spent. You’ve probably heard terms like “wall cloud” “storm inflow”, and “mesocyclone” from weather forecasters. This training explains those terms, but even better, you learn the differences between a “plain” thunderstorm and one which may spawn tornadoes.

Take CERT training

Train to be a Community Emergency Response Team member. The training is free, and covers a lot of very useful information from how to use a fire extinguisher to how to prepare for participation in disaster recovery.

See whether your church or organization has a disaster relief team

If you are already a member of an organization, see whether they participate in disaster recovery. Many organizations such as the Southern Baptist Relief organization and others are members of VOAD – Volunteer Organizations Active in Disasters, and coordinate disaster response through that organization.

Take free FEMA courses

FEMA offers free online training in NIMS, the National Incident Management System, used in disaster response. These generally aren’t required in order to participate in disaster recovery at a local level, but these courses can help you understand the hierarchy and methods used by FEMA during a disaster response. I recommend starting with these courses: ICS-100.b, ICS-200.b, ICS-700.a, and ICS-700.b.

Talk to people who have been active in disasters

You can learn a lot by talking with other volunteers who have been active after disasters. When you get involved in organizations, you can learn a lot by asking questions and listening.

I’ve written that my family was well prepared to survive with no power for a week.

There’s a mnemonic that someone taught me sometime during some disaster prep training. The fact that I can remember the mnemonic and not where I heard it means it’s a good one, I suppose.

YOYO 120

You’re on your own – for 120 hours. Five days. In a major disaster, this is how long it takes to get services to you. It could be longer. Shelter, food, water, waste. A gallon of water per day per person.

Count the people in your house. Now extend that – if your unprepared uncle or brother or mother or elderly neighbor needs help, can you take them in?

Here’s how we were prepared – Mostly it’s because we camp.

Shelter:

We still had our house. We do have tents, but I think it’s a bit unrealistic to think that they would have been useful if the house wasn’t inhabitable. In that case we would be without shelter until we received help or would use the skills of the four boy scouts (and ex-scouts) among us to figure something out.

Food and Cooking:

We have a propane camp stove, several individual backpacking stoves, a lantern, and fuel for them. We also had more than a week’s food in the pantry, a lot of which was not perishable. I was joking during our five days without power here that the worst thing that could happen is that we would have to start eating food we didn’t like. We had about 35 pounds of rice, which would have lasted a long time. I wouldn’t have enjoyed it much, but I was glad we had it. We cooked the food in the frig first, then the frozen food when it started to thaw. After that it was canned and dry food. We ate pretty well. And every day while the power was out, the cat brought a chipmunk into the house and released it alive. I’m not sure whether she was doing her part to provide food.

Unfortunately, she’s continued to do that.

Had we been limited to the cooking fuel we had on hand, we would have needed to be very conservative in its use. As it worked out, my ex-wife had a grill bottle of propane that she didn’t need because she had a natural gas stove, and we had a camping drip coffeemaker that would work on her stove. We swapped. Had the bottle in our gas grill not been empty, we would have had plenty of fuel. For camping, we have a propane “tree” and hose to connect the lantern and stove. It makes it really easy to use a big grill bottle. We were also glad to have spare mantles for the lantern. The ones on it were broken.

Water:

We never lost city water. But it would have been OK if we had. The morning after power went out, I mixed a little bit of bleach water and sanitized every container in our recycling bin. A teaspoon of bleach in a gallon of water will do it. I filled them with water, about 8 gallons in all. We were under a call to conserve, but it seemed a reasonable compromise, as we used almost none flushing toilets or bathing. I also turned off the circuit breakers for all the large appliances in the house – this has several benefits. First, it helps prevent a heavy load on the system when your neighborhood comes back on line. Second, it turns off your stove. If you left anything cooking on the stove, it could cause a fire when the power is turned back on. Third, it keeps the water heater from coming on in case you drain it while the power is off. Once the power was off, I turned off the valve at the water heater. This keeps the water in the water heater from going anywhere else. Your water heater holds 40 or 80 gallons of fresh water during an emergency. By opening the drain valve at the bottom and pulling the test lever on the pressure relief valve, you can drain out what you need. Beyond that, we have a couple of filtration pumps used for backpacking. These could keep us supplied with water for weeks, as long as there is water to be found anywhere. We happen to have a nonfunctional spa in our back yard that we just got and plan to install, and it had another 100 gallons or so of brackish water in it that could have been filtered.

Light:

In addition to the camp lantern we had some LED camping flashlights that worked great. a head mounted one is really handy for when you need both hands.

Heat:

If you live where it’s cold, you need to figure this out. In this recent disaster, it wasn’t an issue for us, as the weather has been really nice. We do have a kerosene heater and 5 gallons of kerosene, which in Alabama can keep a room inhabitable for days.

Which brings us to Carbon Monoxide. Camp stoves, lanterns, candles, and kerosene heaters generate Carbon Monoxide, and it can kill you. Be sure to get adequate ventilation with outside air. That wasn’t a problem this time, as the doors were open most of the time.

Generator:

Wait, what? A generator?

I own the generator mostly to support amateur radio activities, and used it after the power went out until the bad weather was over. I had enough fuel for us to run it for at least 2-3 hours each day, which allowed us to charge all our cell phones and amateur radio batteries. That was nice, as the cell phone system was working pretty well for SMS messages within a day, and for calls after about 3 days. I wouldn’t think a generator an essential item for post households, although we did hook up the DVD player and TV and watch movies on two nights while charging batteries. We lucked out. There have been times when I did not have much generator fuel, but this time my generator can was full, and the lawnmower can was almost full. In reality, there is no dedicated can of gas for the generator – I rotate them so the fuel remains fresh, but I try to always have a full can.

Car Fuel:

We had three vehicles at the house. Each of them had more than 1/2 tank of gas. I try to make sure they don’t get too low, because we live about 22 miles downwind of a nuclear power plant, and because for any number of reasons, I might need to take to the field to help with a weather event or disaster assistance.

So to recap, my order of things is:

Assess the situation. Open the frig quickly and make a mental inventory of what you have. Avoid frequent opening of the frig.

Collect what water you can.

Turn off major appliances at the breaker box

Turn off water to the water heater

Set up the cooking and lighting using camping equipment

Figure out how much fuel is on hand for each device and how many hours a day you can operate it

Decide whether to stay or evacuate (if you can)

Here’s another first-person account of April 27th and after, with some really informative links to some weather resources about the event.

Note that this was rescheduled due to me being busy with disaster recovery. We can talk about that, too if anyone is interested.

–

Please join us on Friday, May 6th at 14:00 UTC for:

Ubuntu and Amateur (Ham) Radio for Ubuntu Open Week

Steve Conklin AI4QR, and Kamal Mostafa KA6MAL

Curious about what you can do with Amateur Radio and Ubuntu?
Curious about Amateur Radio in general?

Steve and Kamal will take questions and do their best to answer them.

—-

Amateur Radio is a hobby and a public service enjoyed by at least a million people around the world. Whether you are interested in transmitting and receiving radio signals around the world to meet new people, in being of service after disasters, or in the technical aspects, there is probably something for you.

Amateur Radio covers a huge number of interests, including local and long distance communications, emergency communications, satellite communications, digital networks, competitions, and electronics design.

Ubuntu offers many software applications related to Amateur Radio. We’ll discuss some of our favorite apps for use in the “ham shack”, and show how you can receive and decode digital conversations and telemetry with Ubuntu and any shortwave radio receiver (no Amateur Radio license required!).

We will be holding an open Question and Answer session:

When: Friday May 6th at 14:00 UTC

Where: In the #ubuntu-classroom and #ubuntu-classroom-chat channels on freenode IRC.

For more information about IRC:

Here’s a web client for IRC:

You don’t have to wait until the session to learn more about Ubuntu and Amateur Radio and meet other interested people. Check out our team information page or drop into #ubuntu-hams on freenode IRC.

73, DE AI4QR

Continuing my exploration of SDR and the Softrock RX/TX Ensemble …

You can catch the beginning of those posts here.

The programmable oscillator on the softrock runs (in my case) at four times the desired mixer frequency. My unit is set to start up at 14.080 MHz, in the 20m band.

But - it would start up with the master oscillator running off frequency, which led to calibration being shifted by about 20 KHz on the band.

I’ve been using an application called usbsoftrock to access the firmware interface on the radio. Usbsoftrock is available packaged for Ubuntu as described here. I think that usbsoftrock is supposed to allow me to calibrate my radio so it will start on frequency every time. I grabbed the source for usbsoftrock, and read the README, and it looks like the proper steps are to run the calibrate command:

$ ./usbsoftrock -a calibrate
Version     : 15.12 fXTALL = 114.440115

Then as  I understand it, I can just set the crystal frequency in the radio eeprom like this:

$ ./usbsoftrock -a set xtall 114.440115
Version     : 15.12

This just resulted in the exact same behavior. Actually, when I ran the calibrate command, the frequency would change to being much closer to where it should be, but it was still a bit off. As soon as I would cycle power, it would return to the original value.

I decided to experiment with writing different crystal frequencies to the eeprom, and had the following results, measuring after cycling power:

Set xtall    |   Output
——————-|——————
 114.265     | 56.3253
 114.2745    | 56.3207
 114.275     | 56.3204
 114.2758    | 56.3200  <——-
 114.285     | 56.3155
 114.440     | 56.2390

Since I want it to start at 14.080 MHz, the correct value is four times that or 56.3200 MHz. Incidentally, I’ve been measuring at top hairpin lead of R13 using a frequency counter.

Having written the correct value, the radio starts up on frequency every time. It’s very close to being dead on, I can tell by listening to WWV on 10 MHz.

I’m not sure why the procedure I thought I should use with usbsoftrock didn’t work. I may investigate that more later. I’ve asked on the yahoo softrock group, and there’s a lot of expertise there. If I get an answer I’ll post an update here. Otherwise, at least here’s a trial and error method for you.

Once I got the radio into a case and out of the rats-nest of cabling that I was using for testing, and disconnected the counter, the signal quality improved drastically. Here’s a screenshot covering the 20m band from about 14.050 to 14.095 MHz. You can see some CW at the left, a bunch of psk31 traffic around 14.070, and rtty around 14.085. It was amazing to see the phone portion of the band, there’s some sort of contest going on this weekend.

My previous two posts are about the Softrock RXTX Ensemble board, and getting it built. After I got mine built, I had trouble finding software applications to use it. Applications are out there, it’s just that I couldn’t find them. I’d be really happy to have something like Flexradio’s PowerSDR available for Linux. That application is great and it’s open source, but it’s Windows only.

(I’m definitely open to advice here, from the Linux SDR people who find this)

I’ve ended up being able to use an application called “quisk” as a receiver, but it required some customizations. My work was all done on Ubuntu Lucid 10.04.

This is not a solution you can just install and run, so be warned. You’ll have to twiddle with it, especially with respect to how your sound devices are configured.

Also, in order for this to work, you will have to have previously installed usbsoftrock as described in my last post, and it will have to be on your default path. This is because quisk starts usbsoftrock in the background to control the SDR board.

When I went looking at quisk, I found an older version on the yahoo softrock group which had been modded to work with the softrock, but it didn’t work for me. I ended up grabbing the latest version of quisk (3.4.8) and copying and modifying some files from the one that was on the yahoo group files area.

Grab quisk from the link above, then also grab this tarball containing two files.

Put the file named quisk_hardware_vk6jbl.py in the directory with the rest of the quisk source. Copy the file named ai4qrdot.quisk_conf.py to $HOME/.quisk_conf.py

At a minimum, you will probably need to edit .quisk_conf.py to set your audio input and output devices. Quisk will receive audio on both stereo channels of the input (actually higher in range than you can hear, up to half the sampling rate). On my system, this is set like this:

name_of_sound_capt = “hw:0”

There’s a script in the quisk directory named portaudio.py, which will print information about sound devices - this may help you find the one you want. You’ll also need the correct input selected in the Ubuntu sound mixer, have it set to mic level, and adjust the volume there. Once you get this right, you’ll be able to see some noise (and hopefully signals) on the quisk display.

In order to hear the selected (tuned) output, you’ll have to have the output device set also. Now for me I was unable to listen on the speakers, which are the same device number as the input I’m using. I would get a split second of sound and then silence. I changed the output to be a pair of USB headphones I use, and that worked. For me, the USB headset device was selected like this:

name_of_sound_play = “hw:2”

A few other things to be aware of - If everything appears sort of ‘mirrored’ around the center of the display, i.e. you tune up in frequency and the signals you see shift up (right) instead of down, then you have the I and Q channels reversed, and need to swap them in these lines in the config file:

channel_i = 0

channel_q = 1

I hope that’s enough information to help. As I was doing it I didn’t really have in mind to document it, only to get something working.

It looks like quisk is capable of transmitting, using AM, SSB, or CW, but as far as I can tell it won’t handle PSK-31 and doesn’t make the audio available for other applications like fldigi. I could be wrong, I haven’t gotten into it very deeply. This may be possible using “jack” but I don’t know.

I’ve also only just discovered sdr-shell, and that looks like it does exactly what I want, with DttSP. In fact, I see that Bob McGwier was one of the starters of DttSP, which invokes full recursion.

In my last post, I described how I ended up finally starting with SDR. I’m experimenting with the Softrock RXTX Ensemble. This kit is a transceiver with 1 Watt output, definitely QRP. It features a USB interface which allows setting the frequency and keying the radio for SSB and PSK31 transmissions. It also has a key jack for CW, and connectors for everything, so you don’t have to hang wires from the board for connections.

Here are some links related to the board:

• WB5RVZ’s Build notes and information
• Ordering page (Tony Parks KB9YIG)
• Yahoo Group for Softrocks

A word of warning - These kits sell out very fast, and apparently Tony is having trouble getting components. One of the effects of the global recession we’re in is that there are shortages of electronic components, so I’m not sure what the availability will be.

The kit has surface mount components, and requires winding transformers and inductors on small toroids. If you’re not comfortable with this then try to find someone to help you with these parts. Mounting Surface Mount Devices (SMDs) without any special tools other than a very fine-pointed soldering iron and a good head magnifier is not that hard, but it really helps to get some pointers and watch someone else do it. If your vision and motor skills are average or better, then you can do it, and it will be a rewarding project.

The kit can be built for a number of “super bands” as described here. The kit comes with all components for all options, which means that 1) you have to pay attention to the instructions while you build it, and 2) you will have parts left over.

I built mine for the 20m/30m/40m option. This is because I’ll be traveling with it, and having both 20m and 40m gives me bands which are open during day and night, respectively (at least as it stands now in the current solar cycle). I also like 30m, so this is a good set of bands for me.

I built it in exactly the order recommended in the build notes, but didn’t actually test it until it was finished. This isn’t recommended, as the various tests in the build notes are helpful in isolating problems before they get compounded. So this is a case of “do as I say, not as I do”, unless you are confident that you can troubleshoot your way out of problems of your own making. I did have one short caused by sloppy lead clipping, which didn’t cause any damage.

The thing that caused me the most troubleshooting time is that the audio signal coming out of the board is labeled “Line In”, and the signal into the board is labeled “Line Out”. Presumably this labeling is for what they should connect to on your computer sound card but I missed that, despite the fact that it is correctly marked on the schematic and block diagrams. 

An aside: The kit includes parts and instructions for a low-pass filter which must be used on the TX output “if transmitting on 30m”. Does anyone know why this would only apply to 30m? Are there stricter requirements for harmonic emissions on 30m? I’ve been meaning to look this up but while I’m writing this maybe I can crowd-source the answer.

One reason I skipped the build tests is that I hadn’t found a good application for Linux that would allow me to control the oscillator on the board using the USB port. There is a ton of information on the softrock yahoo group, in files and in the message archive, but the majority of what’s there relates to using windows applications. I did actually try to use a windows 7 machine to connect to the board, but after losing about 4 hours to erratic behavior caused by conflicts in USB drivers and the application, I gave up. It was a reminder of all the things that I don’t like about windows.

I’m an Ubuntu Linux user (and developer), so I decided to just figure out how to make this all work there, and document it. Everything documented here is for the Ubuntu Lucid 10.04 release.

The one thing you need early in the build is a way to control the oscillator on the board via the USB port. This lets to make sure that it works, and check the quadrature signals to the mixers. On the softrock yahoo group, I found an application named usbsoftrock, which does this. In writing this post, I’ve discovered that usbsoftrock has been packaged for Ubuntu and is available in a PPA by Jonathan, AF6YF (now N6JU). He has some notes here. I’ve not tried this, but hopefully it will work for you and save you the trouble of building it.

Usbsoftrock expects the softrock (USB) device to appear as /dev/softrock. In order to make this happen, you are going to have to add a udev rule. I found a rules file by G3VBV somewhere in my searching of the web. I’m sorry I can’t link to the original because I can’t find it, but I’ve put a copy here. copy that file to /etc/udev/rules.d/88-softrock.rules. You’ll have to be super-user. Make sure it’s owned by root and has permissions 644:

$ sudo chown root:root /etc/udev/rules.d/88-softrock.rules

$ sudo chmod 644 /etc/udev/rules.d/88-softrock.rules

Now restart udev to pick up the new rule:

$ sudo service udev restart

Now, read the 88-softrock.rules file and follow the instructions for adding a softrock group and adding your username to it. Now when you plug in the softrock board, the device /dev/softrock should be automatically created, and you should be able to access it.

Usbsoftrock has an interactive mode that lets you change the frequency through a curses text interface, which is helpful for testing. To invoke it use “usbsoftrock -a interactive”.

That should be enough software to get you through the build. 

Next, how I was able to actually receive signals using the softrock and Linux software.

I’m pretty easily distracted by shiny things. That’s one reason that things get stalled in my project queue. If an opportunity or project of interest comes along, I’ll indulge that and devote some time to it.

I’ve been interested in SDR (Software Defined Radio) for a while. I studied signal processing at university, and I once wrote a prototype FSK modem as a work project. I’ve been following developments, hanging around in the FlexRadio booth at hamfests, and thinking about getting involved “some day”, when I could get in at a reasonable cost (meaning under $100).

I’ve also been wishing for a small QRP (low power) tranceiver that I could use for CW and PSK-31 while traveling. I travel light, so it needs to be small. I have a KX-1 that works for CW, and that size is about right.

A few weeks ago I met Bob McGwier, N4HY on Facebook, because he noticed that we had some interesting mutual friends. Bob has done some really cool things, and is an expert on SDR, so I asked him whether he could recommend a small, cheap introductory SDR rig that was a transceiver. He was very helpful and recommended the Softrock RX/TX Ensemble, designed by Tony Parks, KB9YIG. Tony has brought low-cost SDR kits to a lot of people, enabling a lot of amateurs to get into SDR experimentation. There is a really excellent set of builder information for the kit by WB5RVZ, which helps make the kit accessible to more experimenters.

I dropped an email to Tony, and got an immediate response. So I was already having an amazing week, having connected with two rock stars of the SDR world. Tony told me he had an order in prep, and if I sent him payment via paypal, he’d have a kit for me. I did, and a few days later, the kit arrived.

Now, as of today, I already have the rig running as a receiver, but I’m stopping to document some of how I got here, especially since a lot of the documentation and software applications available are for Windows, and I used Linux.

I’m going to break this up into a few posts for readability. Next, some information about the Softrock RXTX Ensemble.

“At this point, since Ubuntu is beginning to look like a really viable alternative OS, the next big issue is whether it will support the ham radio applications that we want to run. Fortunately, the answer to this question is — yes it will.”

- - Ubuntu Linux for Hams

My Ubuntu Hams badge. Some nerd bling just in time for hamfest.

For some amateur radio operators, the annual Field Day is a big deal. Here in Madison County, Al we put on a pretty big effort, and get to practice our rapid-response skills and be competitive at the same time.

If you are at all curious and want to see a lot of different aspects of Amateur Radio all in one place, come visit this weekend. There will be lots of hams there to talk to about everything that’s going on, and non-hams can even talk on the air, under the supervision of a licensed operator.

While the on-air competitive portion of field day starts Saturday at 1:00 PM and ends Sunday at 1:00 PM, we’ll be starting work at 1:00 PM Today (Friday, June 25th) - putting up four 50’ antenna towers, a satellite ground station, and a VHF/UHF station.

Our location is  250 Business Park Blvd, Madison 35758, just south of I-565.

Here is a google map.

It’s been a great week for the Ubuntu-Hams team. We’ve had a lot of activity on IRC for weeks, but we finally set up some scheduled nets, and had the first of those this week.

Of the four nets on the schedule, we managed to have two - the 80m net ended up moving to 20m because it just wasn’t working for us on 80, and we had a nice round-robin net until the band closed on us. Today we had our first echolink net. There were only two of us, and it was a chance for me to hear the voice of 9W2PJU in Malaysia. Due to his location, power and band limitations, it’s not likely that he and I will be able to make an actual rf contact for a long time.

If you’re an amateur radio operator or want to be, and you are interested in Linux in the ham shack, check out the team page and join us on IRC.

The Ubuntu Hams team was started a year ago, and has seen a lot of membership growth since then. We just finished the first BOF session we’ve ever had at an Ubuntu Developer’s Summit, and it was a lot of fun. As soon as I can I’ll email a summary to the team mailing list. The discussion was wide-ranging, from enabling translation of amateur radio packages, to increasing the number of upstream maintainers that we engage with.

We decided to begin having monthly meetings on IRC for Ubuntu-hams, as well as starting to have some HF nets. If you’re interested in following this, join the team and subscribe to the mailing list. We’ll be having followup discussions there.

Calling all developers of amateur radio software …

Recently there has been discussion in several of the amateur radio development communities that I participate in about establishing standards for interoperability of amateur radio applications.

Discussion has been around protocols and data formats for amateur radio applications, to be used both on a local host and for interaction with web-based applications.

In the last week, the discussion gained enough momentum on the linux-ham mailing list that it was suggested that interested participants take the discussion to the arswd Yahoo group:

http://groups.yahoo.com/group/arswd/

The informally stated purpose is to create an open cross-platform specification that will allow interoperability of applications. This is not aimed at any particular operating system or distribution.

This is still in the stage of having people gather for further discussion, so it’s wide open for contribution.

it would be great to have participation by the principal developers of various amateur radio applications, no matter which O.S. your applications run on. No one knows better than you what would help you make your app work better. No matter what your area of knowledge - logging, sound card modems, satellite comms, contesting … there are probably unique aspects of those applications that should be accounted for in the spec.

I personally see this as a step toward some amazing amateur radio applications, suites, and web-based applications.

Steve AI4QR

Last weekend I went on a two-night backpacking trip in the Sipsey Wilderness Area with ten scouts and a couple of other adults. We had a great time, with two nights with sub-freezing temps. For me this was a milestone, the first backpacking I’ve done in years since knee and shoulder surgeries.

I had forgotten a couple of things - The first was just how many stars (and other objects) you can see from earth when you are far away from light pollution. Adding to the clarity we had clear, cold air overhead from the front that had just passed through. The second thing I hadn’t thought about in a while was how much lower the rf noise floor is away from my house and urban areas. I had my Elecraft KX-1 along, and threw an antenna up into a tree. I ended up not trying to make any contacts because a) It hurt to take my hands out of my gloves and b) there was a CW contest on, and I was not very confident that I could copy well enough. So I spent several hours just practicing copying CW, and made some real improvements. I was amazed by what I could hear! Just like realizing that there are so many stars you normally can’t see, there were an incredible number of signals out there.

I need to get out more often.

Antennas on hillsides - interesting stuff:

I’ve been thinking about how to optimize antennas for HF at my location, which is on a hillside. This provided me with some insight. I’m not sure what I’ll end up with for propagation to the East (over the hill), but to the West I can probably end up with very good results. Modeling will help. I’ll post more when I get to that.

On November 6th I’ll be helping Dave Freese, W1HKJ make a presentation about fldigi to the Huntsville Amateur Radio Club. Fldigi is an amazing open-source cross platform application for communicating using sound card digital modes on amateur radio.

Dave is really knowledgeable about the encoding and error correction used for the various modes, and I learned a lot by helping him with a similar presentation at the Huntsville Hamfest this year. Our demo was cross-platform between Windows and Ubuntu Linux.

There are some really interesting uses being made of fldigi and some companion applications - sending digital files error-free by amateur radio. This is useful for emergency communications in post-disaster situations, when information must be accurately transmitted. Some of these applications do not use point-to-point connections, and therefore allow a file to be received by multiple stations at once. That way, if any station fails to receive the file correctly, they can get a “fill” from any other station who did get it.

It’s possible to perform these file transfers simply by holding the microphone on an FM radio near the computer speaker, and to receive them with a computer microphone near the receiver!

This should be a worthwhile presentation for people with any level of interest or experience in digital sound card modes. For more information see Dave’s excellent web site. Don’t miss his sights and sounds of digital modes page, especially if you’ve been listening to the sounds on the ham bands and wondering what modes they are.

The presentation will be November 6th at 7:30 at the American Red Cross chapter house, 1101 Washington street, Huntsville, AL. This is the regular weekly meeting place and time of the Huntsville Amateur Radio Club.