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The six meter calling frequency and perhaps other calling frequencies on other bands are a bit of a paradox.  Six meters is often dead and will magically open up between areas due to Sporadic E propagation.  You won't know the band is open unless you continually scan the lower end of six meters hunting beacons or someone happens to be calling on the calling frequency.

We have an amateur in the area who likes camp out on the six meter calling frequency and have his voice keyer automatically call CQ for a few hours some evenings.  It's logical to do such a thing as no one will know the band is open unless someone is transmitting and someone receives the transmissions.  But it's terribly annoying to listen to and I find myself getting frustrated when people do this.  I know others feel the same way as well.  Despite being a calling frequency it's impolite to use it for calling for long periods of time.

Perhaps what we should really have are multiple calling frequencies based on areas such as grid square fields, the first two characters of the Maidenhead Locator System (i.e. "FN", "EM", "CN", etc.).  You could camp out on the frequency for your grid square field and call CQ all you like, but if you just wanted to listen for an opening, you could leave your receiver on one of the other grid square field frequencies and not have to worry about a local station clogging the frequency for long periods of time.
Anthony Good, K3NG, is a regular contributor to AmateurRadio.com and writes from Pennsylvania, USA. Contact him at [email protected].

Welcome to Handiham World!

Update: Larry Huggins, KA0LSG, Handiham Volunteer, holds the Wouxun HT on cover of Worldradio

For Handiham World, I’m…

Patrick Tice
[email protected]

Pat Tice, WA0TDA, is the manager of HANDI-HAM and a regular contributor to AmateurRadio.com. Contact him at [email protected].

It’s time for a new episode of Linux in the Ham Shack. I can hear everyone cheering in unison from here. Richard’s Internet service was down for the recording so he had to bring some portable computers over to his father’s house and attempt to get everything done from there. Unfortunately, all did not go well. I was able to cobble together the broken bits of audio into something that sounds like a podcast. There’s even music, some production value and–most amazing of all–actual content. Thank you to everyone who stopped by for the live recording. Because I’ve been so busy over the last couple of weeks, we’re going to be doing it all again tomorrow night, July 27th. Hope to see everyone in the chat room and please enjoy this latest installment of the program. There are lots of new things in the works that I can’t mention right now, but it will all be a lot of fun and it all means more stuff for you out there to listen to. As if you already didn’t have enough to do. Don’t forget to send in that feedback, especially audio feedback. We want to hear from you. Until then, keep it real.

73 de The LHS Guys

Russ Woodman, K5TUX, co-hosts the Linux in the Ham Shack podcast which is available for download in both MP3 and OGG audio format. Contact him at [email protected].

As I mentioned in the earlier Field Day 2010 report, the CUARC group built two antennas for the event.  In this post I will describe the first one of these, an off-centre fed dipole.

The common place for the feed point of the off-centre fed dipole is at a 1/3 : 2/3 split in the arms. This has the advantage of providing low SWR (with a 4:1 balun) at even harmonic frequencies, such as 20m and 10m for an antenna cut for the fundamental frequency of 40m (around 66ft). Whereas a centre-fed dipole will only have the odd harmonics which for a 40m (7MHz) dipole is 15m (21MHz).
Rather than use the traditional off-centre length split of 1/3 : 2/3 for our Field Day antenna, it was decided to follow the design proposed by Richard Formato, K1POO, in two technical correspondences published in QST ^1,2 and followed up with further article with by Dale Gaudier, ³. In this design the feed point is moved closer to the 1/6 point on the short arm, the advantage being stated in the articles that you should get a 200Ω feedpoint there and so a low SWR on 40m, 20m, 15m and 10m bands when using a 4:1 balun, with no need for an antenna tuner unit.  The emphasis on the 15m band is intentional as a low SWR on that band is not usually possible with an off-centre fed dipole with the feed at 1/3 : 2/3 and a 4:1 balun.  Four bands on one 69 foot wire antenna with no tuner looked very attractive for Field Day.

The antenna was cut carefully prior to Field Day and the end insulators were added.  When cutting the antenna the length measurement included the ‘pig-tail’ connections that I have on the 4:1 balun. The diagram below shows the arrangement of the antenna.

On the day the antenna was installed between two trees at about 35ft off the ground. While the second antenna was being constructed (to be featured in a later post) its SWR was measured with my Autek RF-1 antenna analyzer.  The results were taken by Maria, VA3MMI and Gil, VE3JRY and are tabulated below.

_______________________________________________

Band (m)    2:1 VSWR Range (MHz)          Minimum VSWR
40                                                                      3.1 : 1 (at 7.38 MHz)
20                       13.29 – 14.65                            1.4 : 1
15                       21.20 – 22.31                            1.5 : 1
10                      27.78 – 29.25                            1.7 : 1
_______________________________________________

The overall results were very pleasing, although the 40m band was a little disappointing. This higher than expected SWR on 40m was also encountered by Dale, M0AOP/K4DG, and was reported ³ by him to be due to the severe imbalance in the antenna, so requiring a choke balun to remove the stray RF on the coax.  We did not try a choke balun, since we were unlikely to operate on 40m, that was another station’s band of operation.  However we had an antenna tuner unit if we needed to try and tame the SWR. It was very good to see the SWR profile observed in reference 3  was repeatable.

On Sunday morning Maria, VA3MMI, returned with a portable analyzer borrowed from work and did a sweep analysis.  The response is below and markers have been inserted to show the minimum SWR associated with the bands. Thanks goes to Maria for the measurement and the plot.

It would be interesting to remeasure the SWR response again with a choke balun in place.  I expect the SWR will drop below 2:1 within the 40m band as found by the author of reference 3.  If this does happen then four bands and no tuner needed makes this antenna one for serious consideration on HF. Even without a low SWR on 40m the antenna offers three bands and it performed well on 15m and 10m for us on Field Day.

As a final note, I should reiterate the warning by Dean Straw, N6BV, at the end of reference 1 where he warns about using the antenna on 30m, 17m or 24m, as a very high SWR could damage the balun at the feedpoint.

References

1. “Improved Feed for the Off-Centre-Fed Dipole” R. A. Formato, K1POO, Technical Correspondance, QST, May 1996 p76.

2. “Off-Centre-Fed Dipole Comments, Part 2″, R. A. Formato, K1POO, Technical Correspondance, QST, October 1996 pp72-73.

3. “Choke the OCFD” D Gaudier, M0AOP/K4DG, Technical Correspondance, QST, September 1997, pp82-83.

Note: all three of the above papers are collected together in “More Wire Antenna Classics Volume 2″ ARRL, (1999).

The Field Day photographs above are from the Ottawa Valley Mobile Radio Club’s photo gallery.

Alan Steele, VA3STL, is a regular contributor to AmateurRadio.com and writes from Ottawa, Ontario. Contact him at [email protected].

Various QRP related email reflectors and lists are full of chatter about the Flight Of the BumbleBees (FOBB). Comments about the CW being too fast and the weather being too hot at this time of year make it sound like a broken event. IMHO it is far from being broken! It is probably the premier QRP event of the year. And I say, if it ain’t broke… yep, you guessed it, don’t fix it.

Sunday the bands were full of QRP ops, both home based and portable, so the activity really did make a BUZZ despite band conditions that have not been all that helpful to hf qrp contacts.  The weather was HOT, but hey, find some shade, altitude or water and go for it. Historically this is the time of year for this event and as others have commented, it keeps our activity up during the summer time when vacations and mowing the grass take their toll on ham radio activity.

As far as fast cw, I’m not fast (not even close hi hi), but it sure is fun listening to the buzz on the bands rather than QRN and a high noise level with only a few weak signals. Certainly I am not a hard core contester. My cw skills are still in need of practice, but isn’t that what events like this provide? I often have to listen multiple times to get the callsign and info but that repetition and practice pushes my speed and confidence level up every time I try. After listening to a fast op several times I have the info I need and then I jump in and have fun making a contact at speeds faster than my comfort zone. Most of us slow guys can send faster than we can receive, right? Come on in, the water is fine, and FUN!

My XYL, Connie and I drove over to Honeymoon Island State Park on the Gulf Coast in Dunedin, Florida. This is a very pretty beach, not overly crowded most of the time and has been one of the top rated beaches in the US for several years. The weather cooperated, there was no sign of the BP oil spill that has run so many tourists to other locations, and we snagged a primo spot to operate right next to the water.The only negative, if you call it that, was that the view was sometimes distracting, but sure was enjoyable.

My trusty Sierra and Buddistick provided plenty of action so I never switched over to my mini-bac Delta Loop backup antenna. I also stuck to 20m the whole contest since 40m has been in such poor condition here in Florida lately.

One of the great things about these events is the leveling of the playing field. It is fun to contact the guys that write the articles, create the websites and design the equipment that we use for our hobby. My score was modest at 26 QSO’s, 18 Bumblebees and 17 states and provinces but it was one fantastic day of activity for me! Being able to connect with the big guns of QRP was a thrill too!

For me, one of the highlights was when W8DIZ rode over to meet me as I was setting up my site. Diz lives about 3.5 miles from Honeymoon island and is a regular bicycle visitor of this great beach location. I’ve been a customer of his toroid and kit business and have benefited from the info he has shared, not to mention being one of the movers and shakers of the Famous Flying Pigs QRP group. Diz I was honored that you took time out from a busy family day to swing by and say HI! Thanks for the help getting our screen house up too!

Thanks to Adventure Radio Society and the guys that put this event on for all of us. We appreciate the effort it takes and you deserve the very best of 73′s from all of us.

72,

Kelly K4UPG  BB #10

Kelly McClelland, K4UPG, is a regular contributor to AmateurRadio.com and writes from Florida, USA. Contact him at [email protected].

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Matt Thomas, W1MST, is the managing editor of AmateurRadio.com. Contact him at [email protected].

Readers who follow this blog regularly (all five of you in straight jackets) have probably noticed that I haven't blogged much recently.  I'm still alive, in good health, and pumping RF into the atmosphere.  In fact, I've emitted more RF into the atmosphere these last few weeks than I have in quite awhile.  Six meters has been hopping and I re-joined the local amateur radio club to participate in Field Day.  I think I may be getting my radio artisan mojo back that I thought I was losing much of the previous year.

In my Blogger drafts area I have 98 articles that I've started but haven't completed or I've completed but just haven't felt like they should see the light of day.  Some are just titles of quick, fleeting ideas I had for an article but just haven't had the time or inclination to further develop.  Several are April Fool's joke articles.  And then there are the rant or soapbox articles.  I hope to polish some of these draft articles in the coming weeks and months and slim down my drafts area.  Hopefully I don't release any clunker articles in the process.

The web animation I did a few weeks ago with virtual radio artisans Bob and Jane was done on a bit of a whim.  I'm working on a second web animation on a different topic with most of the dialog again coming from online amateur radio forums.  I'm entitling this series of web animations Off Frequency.  I intend to add more characters and other sources of dialog, focusing on this strange hobby we all love and the often strange people within in. We'll see where this goes.

On an aside, I have to give a shout out to KE9V for his Cornbread Road podcast.  I'm hooked on the story and I'm impressed with the production quality of the podcast, and I'm not much of a podcast aficionado.  If you haven't been following Cornbread Road, I strongly suggest you check it out.
Anthony Good, K3NG, is a regular contributor to AmateurRadio.com and writes from Pennsylvania, USA. Contact him at [email protected].