I don’t usually mention special event stations—unless it’s one I’m operating—but since this one is from a museum station, I thought I’d give them a plug……..Dan

The HF and 2-meter Amateur Radio station at Colorado’s Wings Over the Rockies Air & Space Museum is operational, and we just got approval to operate a special event station celebrating the astronaut and NASA festivities on Friday, May 23. We will have a 12-hour special event station operating on 14250 or 7250 kHz (+/-) from 0900 to 2100 Denver time (1500 UTC 23 May to 0300 UTC 24 May). We will provide an 8-1/2 x 11 QSL certificate to confirmed contacts for an SASE.

In addition to opening the new exhibit, “Colorado’s Astronauts: in their own words,” the museum will host ceremonies for the presentation of NASA’s “Ambassador of Exploration Award” honoring one of Colorado’s astronauts, Jack Swigert.

NASA officials will present the award, including a lunar sample (part of the 842 pounds of Moon rocks returned during the lunar expeditions from 1969 to 1972) which will be accepted by his sister, Virginia Swigert and placed on display at the Wings Over the Rockies Air & Space Museum.

In addition to NASA officials and Virginia Swigert, special guests include:
- Jeaneen Spinelli (Jack’s niece),
- other Swigert family members,
- General Hall (Jack’s Commanding Officer),
- Gene Kranz (Lead Flight Director, Apollo 13),
- James A. Lovell (Spacecraft Commander, Apollo 13),
- Fred Haise (Lunar Module Pilot, Apollo 13),
- Ken Mattingly (Original Command Module Pilot, Apollo 13),
- Jeff Ashby (NASA Astronaut),
- Richard Truly (NASA Astronaut), and
- additional Colorado astronauts.

Local officials include Colorado Governor Bill Ritter, other Colorado Elected Officials, and Colorado Space Industry Representatives.

We have been making progress in setting up our satellite radio system in our full-sized Space Station crew module exhibit. I hope it will also be operational in time to have a role in these activities.

Other information can be found via the links on the K0WAR QRZ.Com page.

We held our second One-Day Tech Class yesterday, and I think I can claim success. Twelve folks signed up for the class, and eleven of them passed. This included current member Lisa Manthey and Candy Justyna, XYL of Ig, N0EFT.

Quite a few of the folks that passed learned about it via our local SkyWarn training. One of our club members took flyers with him when he went for the training, and about 20 folks expressed an interest there. About ten of them actually attended the class. I think it’s great that we were finally able to make that connection.

This time, I stressed pre-study, and I think it really paid off. The students seemed more prepared than they were last summer. Some students were so prepared that they decided to bolt after our first break and return at 3pm for the test. All three who did bolt, did indeed return and passed the test.

Onward and Upward
What I’m thinking about doing is to hold these at regularly-scheduled intervals, say ever two or three months. There were several SkyWarn people that expressed interest in the class, but could not make it yesterday. I also think that with more publicity, a regularly-scheduled class would make it easier for others to work this in to their schedules.

I’m also thinking a modest charge might be in order, say $10. Of course, all proceeds–except for perhaps a small amount used to purchase pizza for lunch–would be donated to our club. If 12 people attended each session, five sessions would net us about $500.

On qrp-l.org, there’s been a discussion of the J-Pole antenna. There were various short, incomplete explanations of how it works, some comparing it to a Zepp antenna. I can see the similarity to a Zepp, but must also admit that my understanding of how it works is incomplete.

Fortunately, Ed, K9EW, posted a link to From a J to a Zepp: The truth and its consequences by Gary E. O’Neil, N3GO. While I haven’t puzzled through it all yet, it looks like a very thorough analysis, and includes a number of observations that the author says appear to be contrary to popular opinion:

• Adjusting the feedpoint “tap” is not the proper way to tune a J-pole.
• 300 ohms is the optimal transmission line impedance to use in the construction of J-poles.
• 300 ohm TV twin-lead is minimally susceptible to RF current induced in the feedline coaxial cable, enabling the J-pole to perform well without a balun.
• The “stub” portion of the J-pole is electrically longer than a quarter wavelength.
• The J-pole “shorting bar” can be connected to an earth ground reference if and only if a balun is employed at the antenna feedpoint.
• The velocity factor is the most critical transmission line parameter to consider when designing J-poles.
• J-poles are easy to build, and tune (even by the inexperienced). As a consequence, they are easy to reproduce.

NASA-funded researchers have released to the general public a new “4D” live model of Earth’s ionosphere. Without leaving home, anyone can fly through the dynamic layer of ionized gases that encircles Earth at edge of space itself. All that’s required is a connection to the Internet.

A screenshot of the 4D Ionosphere. Red denotes regions of high electron density where radio communications can be limited to few or no frequencies. Credit: Google

“This is an exciting development,” says solar physicist Lika Guhathakurta of NASA headquarters in Washington, DC. “The ionosphere is important to pilots, ham radio operators, earth scientists and even soldiers. Using this new 4D tool, they can monitor and study the ionosphere as if they’re actually inside it.”

“The best way to appreciate the 4D ionosphere is to try it,” says W. Kent Tobiska, president of Space Environment Technologies and chief scientist of its Space Weather Division. He offers these instructions:

“One, download and install Google Earth at http://earth.google.com

“Two, visit our web site http://terra1.spacenvironment.net/~ionops/ES4Dintro.html and click on the link “Total Electron Content” found on the top navigation bar.”

Wait for the file to load and voila—you’re flying through the ionosphere.”

“Colors represent electron content,” he explains. “Bright red is high density; that’s where radio communications are restricted to few or no frequencies. Blue denotes low density; no problem there.”

Using the intuitive Google Earth interface, users can fly above, around and through these regions getting a true 3D view of the situation. Make that 4D. “The fourth dimension is time. This is a real-time system updated every 10 minutes,” he says.

The ionosphere is, in a sense, our planet’s “final frontier.” It is the last wisp of Earth that astronauts leave behind when they enter space. The realm of the ionosphere stretches from 50 to 500 miles above Earth’s surface where the atmosphere thins to near-vacuum and exposes itself to the fury of the sun. Solar ultraviolet radiation breaks apart molecules and atoms creating a globe-straddling haze of electrons and ions.

Ham radio operators know the ionosphere well. They can communicate over the horizon by bouncing their signals off of the ionosphere—or communicate not at all when a solar flare blasts the ionosphere with X-rays and triggers a radio blackout. The ionosphere also has a big impact on GPS reception. Before a GPS satellite signal reaches the ground, it must first pass through ionospheric gases that bend, reflect and attenuate radio waves. Solar and geomagnetic storms that unsettle the ionosphere can cause position errors as large as 100 meters. Imagine a pilot flying on instruments descending toward a landing strip only to discover it is a football field to the right.

“Understanding the ionosphere is clearly important. That’s why NASA’s Living with a Star (LWS) program funded this work,” says Guhathakurta. Space Environment Technologies, Inc. of California received the LWS grant and they partnered with Space Environment Corp. of Utah and the US Air Force to develop the 4D ionosphere.

The 4D model can be fun and even a little addictive, warns Tobiska, who likes to use it to pilot an imaginary plane over the Arctic. “A growing number of commercial business flights are crossing the Arctic Circle,” he says. “It’s the shortest distance between, say, Chicago and Beijing and many other major cities.”

The ionosphere is particularly important to these lucrative flights. While they are over the Arctic, planes lose contact with most geosynchronous satellites and must rely on “old-fashioned” radio communications—a link that could be severed during a radio blackout. Using the 4D model, a flight controller could examine the ionosphere from the flyer’s point of view and use that information to anticipate problems that could cause a flight to be delayed or diverted.

The proper name of the system is CAPS, short for Communication Alert and Prediction System. Earth-orbiting satellites feed the system up-to-the-minute information on solar activity; the measurements are then converted to electron densities by physics-based computer codes. It is important to note, says Tobiska, that CAPS reveals the ionosphere not only as it is now, but also as it is going to be the near future. “Forecasting is a key aspect of CAPS available to our customers from, e.g., the Dept. of Defense and the airline industry.”

Start your own flight at http://terra1.spacenvironment.net/~ionops/ES4Dintro.html

When I last blogged about this, I simply reported that we’d applied for a grant from the IEEE Foundation. While we don’t expect an answer to our proposal for a while, Jack, WT8N, and I have been brainstorming about how we might use the money. Part of the money we requested were to go towards, “two to four tabletop displays,” and given that we are working with the “hands on” museum, we’ve been trying to come up with exhibits that kids could actually get their hands on.

Accordingly, we’ve come up with several ideas that will attempt to demonstrate some aspect of wireless technology, but in a “hands on” kind of way. What we’ve come up with so far includes:

• Morse Code. Being ham radio operators this is a natural. The question is how to do it. Kids do seem to love to “pound brass,” so getting them to use the key to produce a sound is a no-brainer, but how to get them to learn something is another matter. One idea is to have them type in their name, send that in code, then have them try it. Another is to have two stations and have kids send code to one another.
• Ohm’s Law. The idea for this exhibit would be to have users switch resistors in and out of a circuit, and possibly set the level of a voltage source and have a big ammeter so that they see how changing the voltage and resistance in a simple circuit affects the current in a circuit.
• See your voice on an oscilloscope. Kids would speak into a microphone and see their voice on an oscilloscope display.
  
• Transformer. Similar to the Ohm’s Law display, kids would somehow be able to switch in more or fewer windings and see how that affects the output/input voltage ratio. We’re kind of sketchy on how to actually do this, though.
  
• Tuned Circuit. Kids would tune a capacitor and see how that affects the output frequency of an oscillator. This might be a visual display (oscilloscope) or audio output.
• Directional Antennas. In this display, kids rotate directional antennas and note that when the antennas are pointing at one another, they are able to hear a signal or talk to other kids at second station. We were thinking of doing this with 440 MHz antennas and radios, as the antennas would be of a reasonable size. This might not, however, be legal for unattended operation, even with very low power. Anyone know of a frequency we could use for this kind of thing?

All of these displays would be accompanied by some text that explains the phenomenon.

In addition, to the tabletop displays, we were thinking of conducting regular fox hunts. Kids seem to love fox hunts. One thing we’re wondering about, though, is how well we could conduct a fox hunt inside the museum. That is will the fox’s signal reflect off all the metal inside making  finding it nearly impossible.

Another concern is how safe it will be to have kids running around with 440 MHz Yagi antennas. I’ve done a little surfing on fox hunting, and thought I’d found a way around this by using a loop antenna. One website, though, says that while they are great for direction finding at HF frequencies, they’re not really that good for VHF. Anyone have any experience to share with us on this point?

You know about resistors, capacitors, and inductors, but how about the “memristor”? According to an article in EE Times, “virtually every electronics textbook will have to be revised to include the memristor and the new paradigm it represents for electronic circuit theory.” The new circuit element, which was proposed back in 1971 by Prof. Leon Chua of UC-Berkeley, but only recently invented by HP Senior Fellow R. Stanley Williams, “remembers” changes in current passing through it by changing its resistance.

According to the article:

The memristor behaves like a non-linear resistor with memory–a small, compact and highly energy-efficient means of creating a memory device. But Chua and Williams claim it is also a new type of circuit element that should enable the creation of new devices never before imagined.

An article on this new component has also been published in Spectrum, the magazine of the Institute of Electrical and Electronic Engineers (IEEE).

I want to know when I can buy some from Mouser. :)

I don’t use a calculator much anymore, but companies are still making them, and they’re more useful then ever. Below, find information just sent to me by HP, a company that’s been at it for a while…….Dan

Just wanted to update you on the latest with HP calculators:

• HP calculator blog - Read what’s top of mind for Wing Kin Cheung, the new general manager of HP’s iconic calculator business, and chat with him on his blog “The Calculating World with Wing and You.”
• HP Solve monthly newsletter – Check out HP’s monthly newsletter containing calculation concepts, advise to help you succeed in your field, RPN (Reverse Polish Notation) tips and limited-time HP calculator offers:
  • With the licensing exam season starting in April, read HP’s advice on gaining an edge when taking the FE or PE exam. Of note, both the HP 35s and the HP 33s Scientific Calculators are approved for the FE/PE exams and are the only scientific programmable calculators that allow users to store commonly used equations prior to the exam. (Volume 1, Feb. 2008)
  • Learn why HP calculators are so popular with Surveyors (Volume 3, April 2008)
• New online classes – HP offers convenient, self-paced, interactive computer based training that allow users to see the calculator of choice and the problem set side by side. The newest classes include HP 35s FE/PE exam computer-based training and HP 35s learning module.

I’m not big on working satellites, but this is kind of cool…..Dan

ZCZC AS04
QST de W1AW
Space Bulletin 004 ARLS004
>From ARRL Headquarters
Newington, CT April 28, 2008
To all radio amateurs

SB SPACE ARL ARLS004
ARLS004 Ten New Satellites in Orbit

Ten satellites reached orbit April 28 aboard an Indian PSLV-C9
rocket launched from the Satish Dhawan Space Center. The primary
payloads were India’s CARTOSAT-2A and IMS-1 satellites. In addition
to the NLS-5 and RUBIN-8 satellites, the rocket carried six CubeSat
research satellites, all of which communicate using Amateur Radio
frequencies. All spacecraft deployed normally and appear to be
functional at this time.

The SEEDS satellite is designed and built by students at Japan’s
Nihon University. When fully operational, SEEDS will download
telemetry in Morse code and 1200-baud FM AFSK packet radio at
437.485 MHz. The satellite also has Slow-Scan TV (SSTV) capability.
Several stations have reported receiving SEEDS CW telemetry and the
team would appreciate receiving more reports from amateurs at their
ground station Web page.

AAUSAT-II is the creation of a student team at Aalborg University in
Denmark. It will downlink scientific telemetry at 437.425 MHz using
1200 or 9600-baud packet.

Can-X2 is a product of students at the University of Toronto
Institute for Aerospace Studies, Space Flight Laboratory
(UTIAS/SFL). Can-X2 will downlink telemetry at 437.478 MHz using 4
kbps GFSK, but the downlink will be active only when the satellite
is within range of the Toronto ground station.

Compass-One was designed and built by students at Aachen University
of Applied Sciences in Germany. The satellite features a Morse code
telemetry beacon at 437.275 MHz. Compass-1 will also provide a
packet radio data downlink, which will include image data, at
437.405 MHz.

Cute 1.7 + APDII is a satellite created by students at the Tokyo
Institute of Technology. This satellite will not only provide
telemetry, it will also offer a 9600-baud packet store-and-forward
message relay with an uplink at 1267.6 MHz and a downlink at 437.475
MHz.

Delfi-C3 was designed and built by students at Delft University of
Technology in the Netherlands. It includes an SSB/CW linear
transponder. The satellite will be in telemetry-only mode for the
first three months of the mission, after which it will be switched
to transponder mode. Delfi-C3 downlinks 1200-baud packet telemetry
at 145.870 MHz. The linear transponder, when activated, will have an
uplink passband from 435.530 to 435.570 MHz and a corresponding
downlink passband from 145.880 to 145.920 MHz.
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/EX

The March 2008 issue of High Frequency Electronics featured two articles on impedance matching:

• Improving the Bandwidth of Simple Matching Networks. This article discusses not only the classic L, T, and pi networks designed for a specific frequency, but also other circuit types that allow you to design a broad bandwidth matching network.
• Matching Using Only 50-Ohm and 75-Ohm Transmission Lines. This short article shows you how to use a Smith Chart to match impedances using coaxial transmission lines. It includes a list of references to websites with info on the theory and use of the Smith Chart.

Say what you will about the ARRL, but no other organization could mount this type of legal challenge…..Dan

QST de W1AW
ARRL Bulletin 8 ARLB008
From ARRL Headquarters
Newington CT April 25, 2008
To all radio amateurs

SB QST ARL ARLB008
ARLB008 Court Finds FCC Violated Administrative Procedure Act in BPL Decision

The US Court of Appeals for the District of Columbia Circuit today released its decision on the ARRL’s Petition for Review of the FCC’s Orders adopting rules governing broadband over power line (BPL) systems. The Court agreed with the ARRL on two major points and remanded the rules to the Commission. Writing for the three-judge panel of Circuit Judges Rogers, Tatel and Kavanaugh, Judge Rogers summarized: “The Commission failed to satisfy the notice and comment requirements of the Administrative Procedure Act (’APA’) by redacting studies on which it relied in promulgating the rule and failed to provide a reasoned explanation for its choice of the extrapolation factor for measuring Access BPL emissions.”

The Court agreed with the ARRL that the FCC had failed to comply with the APA by not fully disclosing for public comment the staff studies on which it relied. The Court also agreed with the ARRL that the Commission erred in not providing a reasoned justification for its choice of an extrapolation factor of 40 dB per decade for Access BPL systems and in offering “no reasoned explanation for its dismissal of empirical data that was submitted at its invitation.” The Court was not persuaded by the ARRL’s arguments on two other points, on which it found that the Commission had acted within its discretion.

The conclusion that the FCC violated the APA hinges on case law. “It would appear to be a fairly obvious proposition that studies upon which an agency relies in promulgating a rule must be made available during the rulemaking in order to afford interested persons meaningful notice and an opportunity for comment,” the Court said, adding that “there is no APA precedent allowing an agency to cherry-pick a study on which it has chosen to rely in part.”

The Court continued, “The League has met its burden to demonstrate prejudice by showing that it ‘has something useful to say’ regarding the unredacted studies citation omitted that may allow it to ‘mount a credible challenge’ if given the opportunity to comment.” Information withheld by the Commission included material under the headings “New Information Arguing for Caution on HF BPL” and “BPL Spectrum Tradeoffs.” The Court concluded that “no precedent sanctions such a ‘hide and seek’ application of the APA’s notice and comment requirements.”

With regard to the extrapolation factor, the Court ordered: “On remand, the Commission shall either provide a reasoned justification for retaining an extrapolation factor of 40 dB per decade for Access BPL systems sufficient to indicate that it has grappled with the 2005 studies, or adopt another factor and provide a reasoned explanation for it.” The studies in question were conducted by the Office of Communications, the FCC’s counterpart in the United Kingdom, and were submitted by the ARRL, along with the League’s own analysis showing that an extrapolation factor closer to 20 dB per decade was more appropriate, as part of the record in its petition for reconsideration of the FCC’s BPL Order. The Court said that the FCC “summarily dismissed” this data in a manner that “cannot substitute for a reasoned explanation.” The Court also noted that the record in the FCC proceeding included a study by the National Telecommunications and Information Administration that “itself casts doubt on the Commission’s decision.”

The briefs for the ARRL were prepared by a team of attorneys at WilmerHale, a firm with extensive appellate experience, with assistance from ARRL General Counsel Christopher D. Imlay, W3KD. Oral argument for the ARRL was conducted by Jonathan J. Frankel of WilmerHale. Oral argument was heard on October 23, 2007; the Court’s decision was released more than six months later.

After reading the decision, General Counsel Imlay observed, “The decision of the Court of Appeals, though long in coming, was well worth the wait. It is obvious that the FCC was overzealous in its advocacy of BPL, and that resulted in a rather blatant cover-up of the technical facts surrounding its interference potential. Both BPL and Amateur Radio would be better off had the FCC dealt with the interference potential in an honest and forthright manner at the outset. Now there is an opportunity to finally establish some rules that will allow BPL to proceed, if it can in configurations that don’t expose licensed radio services to preclusive interference in the HF bands.”

ARRL Chief Executive Officer David Sumner, K1ZZ, added: “We are gratified that the Court decided to hold the FCC’s feet to the fire on such a technical issue as the 40 dB per decade extrapolation factor. It is also gratifying to read the Court’s strong support for the principles underlying the Administrative Procedure Act. Now that the Commission has been ordered to do what it should have done in the first place, we look forward to participating in the proceedings on remand, and to helping to craft rules that will provide licensed radio services with the interference protection they are entitled to under law.”

ARRL President Joel Harrison, W5ZN, concluded: “I am very pleased that the Court saw through the FCC’s smoke screen and its withholding of valid engineering data that may contradict their position that the interference potential of BPL to Amateur Radio and public safety communications is minimal. The remand back to the FCC regarding their use of an inappropriate extrapolation factor validates the technical competence of Amateur Radio operators and especially of the ARRL Lab under the direction of Ed Hare, W1RFI. We are grateful for the work of our legal team and especially for the unflagging support of the ARRL membership as we fought the odds in pursuing this appeal.”
NNNN
/EX