WA5ZNU

Ham Radio Technician Test in XML and XForms, redux

2010-01-15T17:29:00.005Z

Chris Wallace saw my Ham Radio Technician Test in XML and XForms post and pointed out a few simplifications that could be done:

eliminate syllabus (I mechanically produced the XML from the original NCVEC document, and left in the syllabus, which as Chris points out is redundant.)
Changed some obviously unique element values to ID attributes
Fixed a few typos

I've taken Chris's data and fixed one more typo (question T7C09 wasn't RNC valid), and re-indented it back to two spaces. I have updated the RNC schema and Ham radio technician tests to use the new data. Thanks, Chris!

Adding the images would be a good next step. Probably I will split them out into individual files and add relative URI references to them within the document; the XForms display can use the XForms output element with a mediatype of "image/*" to display.

Chris also has on his page an XQuery presentation of the test, plus some starts at interactive versions. I believe XForms is more suitable for the interactive version, and XQuery and XSLT for a static presentation; so in some sense, Chris and I are doing things backwards, as I started from a static version and he's started from an interactive version. But I'm sure we'll all learn something fun.

A bit of background: Dan McCreary and Kurt Cagle are strong promoters of the XRX approach, combining XML, XForms, XQuery, and XSLT with REST. I do this in my Day Job, which is coincidentally at Xerox, but there's no connection between the name XRX and Xerox, nor is Xerox interested in my ham radio work!

I'm going to continue to use this test pool as a use case for XForms 1.2 Future Features for making the interactive part of the testing easier to author. XForms 1.1 has some features (such as the ability to add nodes) that will make it possible to update the test instance with spaces for answers, even without the cooperation of the original test author, but ideally XForms 1.2 would capture this use case and make it easier to describe declaratively.

Ham Radio Technician Test in XML and XForms

2010-01-13T23:58:00.005Z

With the release of the new Technician (Element 2) test data from NCVEC, I've produced an XML version of the test data (with schema). It doesn't yet include the figures. I also created an a XForms page (works in most browsers) that will let you view the questions and answers.

Chinese OTH Radar

2010-01-12T16:02:00.004Z

With the events in China, it seems likely that the interference on 40m and 60m is from either Chinese or Taiwanese Over-the-Horizon Radar.

Shown here are images from fldigi for the close-in spectrum and quisk with the 96 KHz spectrum, both from an Elecraft K3.

It definitely occurs in bands. There's a strong one in the 60m range, and another just below 40m (shown). It extends into the lower portion of 40m as well, though about 20dB less strong.

K12G (K12M) audio amplifier tube kit

2009-12-07T02:09:00.004Z

I built an S5 Electronics K12G amplifier kit, a new version of the K12M kit. The kit came without a chassis. Though S5 does offer a chassis, the style wasn't one I wanted, so I built it on an LMB box as others have done. I need to do a little more painting, but it's in use and working now. This page describes some of the choices I made.

QRPacificon / Norcal QRP / HFPack Dinner

2009-10-09T22:24:00.002Z

Although the Norcal QRPacificon 2009 page doesn't say the location, there is a dinner tonight according to James KA5DVS:

Location is the Hometown Buffet in Milpitas: 212 Ranch Dr Milpitas, CA 95035 This is just across 237 from the hotel. There is a reserved area for Norcal QRP starting at 5:30PM and the HFPack folks are most welcome to join us.

(previously reported)

Difference Engine 1

2009-09-28T00:59:00.003Z

A copy of the portion of Babbage's first Difference Engine that was built. This one is under glass, and was made by IBM in the 1970's.

Babbage's Difference Engine

2009-09-28T00:58:00.003Z

Babbage's 2nd Difference Engine, built in London in modern times and on display at the Computer History Museum in Mountain View. You can see them operate this one daily.

Europe Beam Pattern

2009-09-25T04:36:00.004Z

Today in celebration of sunspots I pointed my beam at 30 degrees (Europe) and left fldigi and PSK Reporter running. When I got home I saw signals throughout Europe and Asia and the US, but a particularly strong line through Europe. Sure enough the line is at 30 degrees. I know the SteppIR pattern isn't that tight, but what a coincidence!

QRPacificon October 9/10 2009 in Milpitas

2009-09-20T04:07:00.000Z

Pacificon is likely not to be with us next month, but the Norcal QRP is having an activity in Milpitas, and HFPack group will also be participating. The event will take a recess for the ASVARO Flea Market on the Saturday 10th in the morning and resume in the afternoon. For more information, read below or visit

http://norcalqrp.org/pacificon09.htm

-------- Original Message --------

Subject:	[QRP-L] QRPacificon 2009 additional details
Date:	Tue, 1 Sep 2009 15:44:36 -0700 (GMT-07:00)
From:	James Bennett

QRPacificon 2009 will be held October 9 and 10th this year in Milpitas at the Crowne Plaza Hotel:

Crowne Plaza Hotel
SAN JOSE-SILICON VALLEY
777 BELLEW
MILPITAS, CA 95035
Hotel Front Desk: 1-408-3219500 | Hotel Fax: 1-408-3219599
http://www.ichotelsgroup.com/h/d/cp/1/en/hotel/sfomp

The hotel is located in Milpitas just a short distance from the San Jose Airport has a complimentary airport shuttle.
Free parking for guests and attendees of QRPacificon 2009.

Hotel booking link for QRPacificon 2009 rate of $65 per night :

https://resweb.passkey.com/Resweb.do?mode=welcome_ei_new&eventID=1457326

If you do not wish to book online, please call 888-233-9527 to make reservations and ask
for the Norcal QRPacificon 2009 rate of $65

QRPacificon 2009 Events schedule
Silicon Valley surplus store tour Friday afternoon

No host dinner Friday evening at 5:30 (location to be announced)

Meet and greet in the hotel ballroom along with vendors and swapmeet ~7-11PM

Saturday morning is the De Anza College Electronics Fleamarket: http://www.electronicsfleamarket.com/
Folks often arrive with flashlights before daylight to get the best bargans. The location in Cupertino is about a 20 minute drive from the hotel.

We will start presentations at 10:30 and will have a great lineup of speakers. Presentations will run through the day

Lunch will be 12:30 to 2PM with presentations following until 5PM

Saturday evening is dinner on your own 5-7PM

At 7 we will regroup in the ballroom for an auction. Due to time constraints, we will limit it to one item per
seller. So bring something surplus to you that needs a new home.

We will also have door prizes and lots of fun so come out and join us for QRPacificon 2009.

Doug, James and the Norcal QRP Club

USB 5V Car power adapter converted to APP

2009-08-22T21:44:00.004Z

I got a 5V USB power adapter for my car, but it broke and fell apart. I retrieved most of the parts, but the tip was lost. So I took it apart, and found broken wires and bad solder joints. I replaced the tip with an Anderson PowerPole connector.
Read more about my USB car adapter converted to Anderson PowerPole.

HP5216A Frequency Counter

2009-08-22T19:35:00.006Z

At the ASVARO Electronics Flea Market I bought an HP-5216A frequency counter. It needed a new power cord, and some other TLC.
Read my HP5216A Frequency Counter Saga.

Arduino - High Sierra Sidekick Antenna Controller

2009-08-17T02:48:00.005Z

I'm building an Arduino-based High Sierra Sidekick antenna controller.
See current status.

Jackson Harbor Press LF receiver

2009-06-19T22:36:00.003Z

I built a Jackson Harbor Press LF receiver kit and had some fun with NDBs, DGPS, WWVB, and other assorted LF noises. Read More.

12,877 new hams in the last year

2009-06-17T05:58:00.002Z

K3UD reports on QRZ.com that the totoal number of US amateur radio operators increased by nearly 13,000 from June 15, 2008 to June 16, 2009. javascript:void(0)

SP2FAP/FF (World Flora-Faura Greendays)

2009-06-10T05:47:00.000Z

I heard SP2FAP calling CQ as SP2FAP/FF on 14.040. The suffix seems to be related to "World Flora-Fauna GreenDays" and since SP2FAP was sending "SPF-025" I think that means he's in Park Krajobrazowy Wysoczyzny Elbląskiej which seems to be quite a pretty picture. I was running 5W to the SteppIR from my K3. OM was 599 with some flutter, but had no trouble hearing me when I timed the pile-up right, and I got a 599 and a FB QRP, as I said I was QRP after he answered. (There wasn't much of a pile-up and it seemed like a fun event.)

EMU-0202 now works at 96KHz on Linux

2009-06-09T05:22:00.003Z

I bought my EMU-0202 at the beginning of 2009, but it only worked at 44.1KHz. Now we've got it working at up to 96Khz in Linux, with an Alsa change forthcoming.

Here's the story: Shortly thereafter Creative released Mac USB drivers and I spent some time looking at the source and saw there were two ways to set the sampling rate: a "direct" method and a "clock" method. The "Extension Unit" code confused me, and I never got around to mapping between the Mac USB and the Linux USB stacks.

But just recently "mellowman" described a patch to get 48Khz sampling working. Over at UbuntuForums "v.stiff" reported success, and I then figured out the quirk to extend it to the full range. CannibalZerg either took my patch or figured it out alone, and we've all tested it and it works!

So I have got the EMU-0202 working at up to 96KHz on Linux. Others report the 192Khz sampling working on the EMU-0404, but the 0202 says you have to disable the input monitor before doing that, and it's not clear to me that that's working yet.

Why's this useful? Well, it lets me use my Quisk K3 LPPan package to see 96Khz of the band instead of 44KHz, a major improvement.

Science: Experiments vs. Wolfram Alpha

2009-05-18T20:44:00.003Z

This morning I thought about a fun science experiment for kids: Use a laptop with a sound analysis program such as fldigi to use its FFT to measure the audio doppler shift from an oscillator carried aboard an oncoming bicycle or car. If you know the frequency of the audio source and the velocity of the vehicle, you can calculate the speed of sound. Then, having measured the speed of sound, you can use the laptop to sample and display the varying velocity of a vehicle. A GPS might be good for calibrating the initial vehicle velocity measurement.

Or, you could just skip the experiment and do it all in The Matrix.

Radio Shack SA-10 Audio Amplifier

2009-05-03T19:25:00.002Z

I have a Radio Shack SA-10 Audio Amplifier which I use with my Squeezebox. It's surprisingly hard to find a good, inexpensive small audio amplifier with RCA inputs these days; most of the industry now makes amplifiers with proprietary Apple connectors.

This SA-10 has always had an intermittent buzz to it, and a low-level hum. I took it apart and didn't see any obviously blown capacitors, so I did a search and found a quick review article on the Realistic SA-10 Audio Amplifier by Joe Roberts. Joe points out that C108 is perhaps under-rated for its job, so I replaced it with a 50V one I had on hand. We'll see if that takes care of the intermittent buzz.

The power cord is a two-line one that goes directly to a transformer. The hum went away when I grounded the case, so I fashioned a third-wire for it and am now enjoying a bit of the old Ludwig van.

Python K3lib Update

2009-03-13T06:04:00.002Z

I've updated the K3 Python rig control library to include a time setting function and a few other new methods. I'd been intending to write a time setter, but David W4SMT provided explicit instructions on how to do it. I read about the eighth bit in the K3 programmer's guide and guessed at 50ms timeouts in a few places.

Grab the Python-rigcontrol package and install it, and then run k3fixtime

tar xzf python-rigcontrol-0.3.2.tar.gz
cd python-rigcontrol
sudo python setup.py install

6W/DL2RMC (Senegal)

2009-01-26T17:58:00.000Z

I heard 6W/DL2RMC on 14.027 and spent a lazy 20 minutes calling at 120W on my K3 and SteppIr. Africa is difficult from here, so I appreciate the OM operating from Senegal. QSL via DL1RTL.

EMU 0202 USB sound device

2009-01-15T21:02:00.004Z

I bought an EMU-0202 sound device from Sweetwater. (Actually I got their demo model for $10 off.) The Sweetwater folks have been very attentive, and asked what my plans were. I told them Linux and amateur radio, and they didn't bat an eye, though their main business is of course music. They said they'd report my interest in Linux support to the manufacturer. Hopefully that will result in some official support for the ALSA developers on the project from EMU.

Briefly, I found that in Ubuntu 8.10, 48Khz stereo input works with certain bit formats, and 48Khz output as well. 96Khz is recognized, but just produces a bunch of aliases. 192Khz causes segfaults in the application. Also, the device can't be plugged in during boot as it causes a hang very early on.

Patrick W9PDS reports that he's had better luck using raw ALSA builds as described here, but it's a dicey non-packaged installation.

Update: 44.1Khz works; 48Khz does not. The Creative Drivers page claims that it now defaults to 44.1Khz even after a power reset. Maybe the OSS Mac drivers will help.

K3/K2 and Rotor Python Rig Control (with SteppIR on the way)

2009-01-12T04:45:00.004Z

I've been using this Elecraft K3/K2 rig control program in Python for a few years, adding bits as I needed them. It's both a set of command line utilities and a small library. Also included is a rotor control package for the Idiom Press controller. A SteppIR command library is in the works (being re-coded from C).

I've recently packaged it up into a release; it may have some issues, but I decided to go ahead and release it anyway.

Next up: Web libraries, a REST based interface, and integration into QUISC (which I was on the verge of writing when I found someone else had already done it).

By the way, don't forget hamlib if you're doing C programming. This is a convenience package for me to experiment with Python control.

Update: now a Python module Download

101-Led Wreath

2008-12-29T02:38:00.008Z

We made a wreath totally out of LEDs and posted it on Instructables. It turns out they're running a contest for holiday decorations, so vote for it (once you log in...)!

Update: We won a runner-up prize! Thanks to all who thought this was a worthwhile project.

Power Supply

2008-12-04T04:56:00.005Z

I found a stash of old Lambda linear regulated power supplies. They were so old, the regulator IC was in a round metal can with 8 gold wire legs coming about 1/2" long, and the circuit board was all wavy, hand-drawn lines. Still, I wanted to make at least one of them work. So I cranked it up from 12v to 13.2V and put it in a Radio Shack case, fused in and out, with an EMI filtered IEC connector from Halted and a red/green LED switch.

Now I have a 13.2V/5A linear supply, which I guess I can use for charging my LiFePO4 batteries (which need about that).

Why did I do this? One of my favorite science fiction authors, Stanislaw Lem, offers a glimpse: In the introduction to Lem's book "Mortal Engines," Michael Kandel quotes Lem:

In his autobiographical essay The High Castle, [Lem] writes: "I used to be a philanthropist to old spark plugs, I would buy parts of incomprehensible gadgets, I would turn some crank or other to give it pleasure, then put it away with solicitude. . . To this day I have a special feeling for all sorts of broken bells, alarm clocks, old coils, telephone speakers."

ARRL FMT 2008 Results

2008-12-01T03:10:00.003Z

Alan WB6ZQZ encouraged me to participate in the ARRL Frequency Measuring Test. I heard W1AW and WA6TZY on 40m but neither on 80m, probably due to time confusion. I got two of the four frequencies measured at less than 1 Hz, and the one was off by 1.35Hz. All four were under 2Hz, and my final differences were both under 1Hz (due to cancellation of errors). Here are the results. Alan was one of only three stations to get all measurements within 1Hz.