Here’s One for All You Propagation Gurus

This evening, just after dark, I called CQ on 40m CW. On the second call, VE3QO, in Ottawa, ON replied to my call. On that first transmission, he was at least 10 dB over S9, and that’s saying something because the S-meter in my IC-746PRO rarely reads anything over S9. Unfortunately, on the next go-around, VE3QO was a lot weaker, and on his third transmission he was nearly unreadable.

This is not the first time that I’ve noticed this phenomenon. It often occurs just after it’s gotten dark. In fact, I can often predict that this will happen by how strong a station is on his or her first transmission. The more out of the ordinary the signal strength, the more likely it is that the station will also disappear quickly.

My question is what propagation mechanism is causing this behavior? Is it perhaps the combining of the F1 and F2 layers? If that’s the case, why is the calling station so unusually strong on the first transmission?

FeedBurner Deleted All My Subscriptions!

I’m sorry to say this, but somehow FeedBurner has deleted all of the e-mail addresses of folks who had subscribed to my blog via e-mail. If you were one of those, please resubscribe by typing your e-mail address into the textbox at the top of the right column.

If you weren’t previously a subscriber and would like to be, you can also type in your e-mail address there. I’d love to have you as a subscriber.

According to IEEE, Pocket Protector Invented by Michigan Engineer

According to the Institute of Electrical and Electronic Engineers, the pocket protector was invented by a Michigan engineer. Here are some snippets from the IEEE History Center Web page, ” Hurley Smith’s Pocket Shield .”

The original pocket protector was invented by Hurley Smith during the Second World War. He was born in Bellaire, Michigan in 1908 and spent his first few years there. Unable to formally attend school, he completed high school by mail. In his mid-twenties he had earned enough to return east and attend college. He enrolled at QueensUniversity in Kingston, Ontario. He earned a Bachelor of Science in Electrical Engineering in 1933. His first job upon graduation was marketing newly invented Popsicles to retailers in Ontario. He said that his diet consisted mostly of Popsicles that first summer. 1933 was not a good time to be graduating from college.

While working in Buffalo, Smith was concerned not only about the ink and pencil stains that would get on the white shirts that were the required costume for any engineer in those days, but with the fraying around the edges of the pocket that the pressure from items in the pocket produced. Back then, the traditional housewife purchased shirts with the expectation that would last for a long time even with constant washing, bleaching, and ironing.

He constructed his first prototype in the attic of his house Buffalo, having modified his wife’s ironer to heat the plastic enough to bend it properly. He modified the equipment over the years and by the time he moved to New Hampshire, the production of pocket protectors promised to provide enough income to allow him to quit engineering. He wanted to move the family to a location that was more economically promising. In 1949 he packed up the family and moved to Lansing, Michigan.

NOTE: I still have a ton of nifty pocket protectors that I’m selling for $2 each. For more info, click here.

Three Random Links

Three random links from my pile of “links to post one of these days.”

  • HP Archive. This site is run by Glenn Robb, an Electrical Engineer and HP aficionado. It’s goal is to help others collect, preserve and enjoy vintage HP equipment and literature. By making hard-to-find documentation easily available to all, it is hoped that others will begin collecting HP, and help preserve the shrinking supply of vintage materials. This site will serve to organize a community of collectors, experts and gather volunteers to work together towards a common goal of preservation.
  • Simple CPO. Build this simple code practice oscillator (CPO) in an Altoids tin. The straight key is mounted on the lid.
  • Surface-Mount Kits. Nightfire Electronics offers a number of different kits and prototyping boards for surface mount circuits.

Let’s Publish a Study Guide for Kids

At a concert Sunday afternoon, I ran into a guy who was in one of my One-Day Tech Classes. He’s really gotten bit by the ham radio bug, and he told me that his ten-year-old daughter has shown some interest, too. He went on to say that he tried using my study guide, but that it was just too dry for his daughter. She needed more explanation.

Well, that comment, and my recent posting about The Manga Guide to Electricity, got me thinking that if we really wanted kids to get into ham radio, then we need to write something like The Manga Guide to Ham Radio.

The thought of doing this both excites me and dismays me. It excites me because I think it—or something like it—would be the perfect way to get more kids interested in ham radio. It dismays me because I’m not sure that I know enough about manga, or about how to write something for kids, to actually pull this off.

Having said all that, anyone want to help me do this?

N1JER Does it Again!

Jeremy, N1JER, hasn’t been a ham long, but he’s really gotten into it in a big way, building kits and homebrewing QRP stuff. His latest creation he calls the “Toilet Paper L-Network Tuner.” The name comes from the material he used for the coil form.

Here’s what he posted to the qrp-l.org mailing list:

I shot a video documenting this project, and have posted some photos.

Overview:

  • Uses the standard L-Network out of the 2008 ARRL handbook, pp. 19.44 and 19.45.
  • Borrows the switched inductance coil idea from KD1JV’s ALT, and KI6DS’s SLT.
  • Uses an air coil formed around a Toilet Paper roll with multiple tap points.

Details:

  • Uses a varicap out of a junk AM/FM radio I found on the street.
  • Uses 1 insulated binding post, and 1 binding post that connects to the chassis for ground.
  • Uses an array of inexpensive switches that are soldered together.
  • I used a formula to have each switch control a coil that is
    progressively smaller. In order from left to right ~7uh, ~4uh, 2uh,
    1uh, and 0.5uh. I didn’t measure the actual values, but did pay strict
    attention to how the coils went on the TP. Each coil can be turned on
    independently so I can have 2+1+0.5 = 3.5uh.
  • Total cost was about $11 USD. (including value of junkbox parts).

In use:

  • Using a 51ft wire with a peak at about 30ft and a 33 ft ground wire.
  • I get a solid dip at 40m. (Tested using KD1JV ‘Tenna Dipper the LED gets very dim, but I don’t know the actual SWR).
  • Using same setup 30m on 20m the LED can go completely out.
  • On 80m there is a very slight dip, but I wouldn’t think good enough to operate.
  • I made one contact with this using my 40m 3w Wilderness SST, ~750 miles.

Have a great day everyone,

Jeremy Chase, N1JER
http://jeremychase.net

PR Idea: Posters

Steve, KD8BUN, started a thread this morning on the ARRL PR Reflector:

I was wondering if you had ever thought of perhaps putting together some full size posters for use in promoting amateur radio and then leave a small space at the bottom for groups to add there contact information. I wanted to mention it to you since you could probably get it done easier, cheaper, and make it available to more people than I have the ability to, especially with my limited resources. I thought the “when all else fails brochure” would be great material and of course one based on the hobby aspect would be good to. I thought it might be possible for you to get them made by whom ever does the ARRL brochures. It would look alot more professional than what we try to put together and there would be some solidarity in using the same posters overall. There may be some times to still make stuff but it would be a nice additional tool to make available to the amateur community and PIOs.

Lots of people jumped on this. Neal, WA6OCP, replied:

I have used posters for Field Day to communicate various aspects of ham radio. It’s not possible to engage everyone that stops by in a multi-faceted conversation. Also, some people prefer to just browse and read.

I have a trifold stand-up poster that describes Amateur Radio. I used pictures from an old ARRL calendar and added captions. I also have a poster that tells about ARES, one that explains Field Day, and one that uses press clippings of amateur involvement in fires, floods, and even the earthquake in China. Of course these are all supplemented by various handouts from ARRL.

Pat, KC8TRW, noted:

Once upon a time, there were two 8.5 x 11 posters available for download from the ARRL website, but a quick search of the site doesn’t list them any longer. I do have copies in my files. They certainly were not as slick or as eye catching as either the “We Do That” or “When All Else Fails…” brochures, but they are attractive enough. Given that these days, as I understand it, almost all graphic work from HQ is done on either Adobe Illustrator or CorelDRAW, I don’t doubt that the original layouts for both of these brochures are filed on disk in vector format. The nice thing about this is that it only takes a couple of keystrokes to turn off the layers with the text, and the artwork can be resized without concern that they suffer from “jaggies.” Whether or not HQ would want to do that is another matter, however.

Gary, K2GW, said:

The league has some very talented graphics designers. I’m sure they could take the themes of the three current public relations brochures (Hello – It’s fun!; We Do that- Technology, and When all else fails- EmComm) and pretty easily design three corresponding 18 by 24 posters that match the graphics, and professional, modern style of the current brochures.

Local clubs could then use them either as individual posters by adding their club name to some white space at the bottom, or cutting the white space off, apply them to a trifold “”science fair project” as the background for a tabletop display.

That way clubs have a starting point for effective PR displays.

I hope that the ARRL pounces on this. I would love to have a large poster along the lines of the We Do That! website and brochure. If it were in vector format, I’d take that design down to the local sign shop and have a large banner printed that we could hang at our club events.

More QSLs!

Yesterday, I received a couple more QSL cards from stations whose callsigns spell words—K4IN and N4PEG.

n4peg-k4in-qsl

I love the K4IN card, even though he got my callsign wrong. It was very nice of him to create a card just for me. Thanks, Gerald!

On his card, Ron, N4PEG, writes,”p.s. You would have loved my old call from thirty years ago in Chicago—WD9ARM. If I had a card, I wouldl have sent it. I had contacted the WDxARM calls and arranged skeds to get their QSLs.” That’s very cool.

FCC Denies Petition to Increase Size of Amateur Radio Question Pools

I got this via an ARRL maililng list.

We can argue about whether or not the tests should be more difficult, and I think a case could be made that the Extra Class test should be tougher, but I’m a bit aghast that the FCC says in this denial that,

the purpose of the examinations is not to demonstrate an applicant’s comprehension of certain material, but rather to determine whether he or she can properly operate an amateur station.

If that were the case, then why even bother with having three different classes of license? This just doesn’t make any sense to me. How about you?

Dan

QST de W1AW
ARRL Bulletin 16 ARLB016
From ARRL Headquarters
Newington CT March 20, 2009
To all radio amateurs

SB QST ARL ARLB016
ARLB016 FCC Denies Petition to Increase Size of Amateur Radio Question Pools

In April 2008, Michael Mancuso, KI4NGN, of Raleigh, North Carolina, filed a petition with the FCC, seeking to increase the size of the question pools that make up the Amateur Radio licensing exams.Mancuso sought to increase the question pool from 10 times the number of questions on an exam to 50 times more questions. On March 19, 2009, the Commission notified Mancuso that it was denying his petition.

In his 2008 petition, Mancuso claimed that the current question pool is too easy to memorize and “that there has been a significant increase in the number of Amateur Radio operators receiving their licenses over at least the last decade or more who do not appear to possess the knowledge indicated by the class of license that they have received. Most discussion about this topic, both on the air and on Internet forums, generally refers to these widespread observations as the ‘dumbing down’ of Amateur Radio. It has been widely assumed that the cause of this observed situation is based upon the subject material addressed by the license examinations, that the material requirements specified for the examinations does [sic] not meet some minimum level of knowledge expected by some or many in the Amateur Radio community.”

The FCC pointed out to Mancuso that each applicant for a new or upgraded Amateur Radio operator license “is required to pass a written examination in order to prove that he or she possesses the operational and technical qualifications required to perform properly the duties of an amateur service operator licensee, i.e., that he or she is qualified to be an amateur service licensee.”

The Commission summed up Mancuso’s petition, saying, “You argue that the current question pool size is no longer adequate, because online practice examinations enable examinees to memorize a question pool without fully comprehending the subject matter being tested. Consequently, you propose to increase the size of the question pools, in order to hinder memorization.”

The Commission concluded that Mancuso did not present grounds for the Commission to amend its rules: “As noted above, the purpose of the examinations is not to demonstrate an applicant’s comprehension of certain material, but rather to determine whether he or she can properly operate an amateur station. Moreover, your contention that there has been ‘a significant increase in the number of Amateur Radio operators…who do not appear to possess the knowledge indicated by their class of license’ is not supported by any data or facts.”

The FCC pointed out to Mancuso that the Commission’s Rules only dictate the minimum number of questions for each question pool for the three Amateur Radio license classes. This, the Commission told Mancuso, “does not prevent the National Conference of Volunteer Examiner Coordinators (NCVEC) from increasing the number of questions in a question pool should it decide that this is appropriate. We conclude, therefore, that the petition presents no evidence of an existing problem or other reason for a rule change.”
NNNN
/EX

Electricity for the Manga Generation

I just received this press release today, so I haven’t actually seen the book yet, but it looks like it would be fun……Dan

The Manga Guide to Electricity
Learn About Electricity in a Shockingly Fun Way

San Francisco, CA, March 19, 2009—Rereko is just your average high-school girl from Electopia, the land of electricity. Except she’s completely failed her electricity exam! Now she has to go to summer school on Earth—and this time, she has to pass. Luckily, her ever-patient tutor Hikaru is there to help. So begins the The Manga Guide to Electricity (March 2009, 224 pp, ISBN 9781593271978), the charming third volume in a series of technical EduManga titles from San Francisco-based geek book publisher No Starch Press.

The Manga Guide to Electricity combines an entertaining plot with authentic manga comics and lessons that offer readers a unique introduction to the world of electricity. Readers learn alongside Rereko as her tutor explains the basics of electricity by examining everyday devices like flashlights, heaters, and circuit breakers.

“I’m really excited about this latest Manga Guide,” said No Starch Press Founder Bill Pollock. “I can’t even count the number of people who have no clue about how electricity works or what diodes, resistors, and capacitors do. This is a great and painless way to sort through the mumbo jumbo.”

The real-world examples in The Manga Guide to Electricity teach readers:

  • What electricity is, how it works, how it’s created, and how it can be used
  • The relationship between voltage, current, and resistance (Ohm’s law)
  • Key electrical concepts like inductance and capacitance
  • How complicated components like transformers, semiconductors, and transistors work
  • How electricity produces heat and the relationship between current and magnetic fields

As they progress through the book, readers will explore more abstract concepts of electricity like electrostatic force, Ampere’s law, and the Seebeck effect. Co-published with scientific and technical publisher Ohmsha, Ltd. of Tokyo, Japan, The Manga Guide to Electricity will make learning about electricity a shockingly good time for readers of all ages.

About the Author
Kazuhiro Fujitaki is a lecturer at the Tokyo Metropolitan Vocational Skills Development Center. He has written a number of books on electrical engineering and runs a website offering useful information about Japan’s qualifying examinations for electrical technicians.

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