May 13, 2009Editor: Ward Silver, NØAX
IN THIS ISSUE
NEW HF OPERATORS - THINGS TO DO
South America is rare on CW it seems, but the All America Contest sponsors are aiming to change that! Point the beam south and you will hear some of our South American friends. Remember that they are in the middle of their autumn, with lowered noise levels on the low bands, so this might be a good opportunity to pick up some low-band DX that you might not hear during the rest of the year.
No bulletins in this issue.
Oops - I plead guilty to RJ-overload. The fellow sitting next to EY8MM in the picture last time was BOB Ferraro, W6RJ, not Jim. (Thanks, Steve K6AW)
Complete information for all contests follows the Conversation section
NEWS, PRESS RELEASES, AND GENERAL INTEREST
ARRL Contest Branch Manager, Sean KX9X announces a change in the structure of the June VHF Plaque program, beginning with next month's contest. The ARRL Programs and Services Committee voted to award plaques based on ARRL Division, just like all other ARRL plaque programs. This recognizes the geographic diversity in VHF+ contesting and will foster more competition on the Section and Division level. The change in structure has created over 100 plaques on the Division level that are available for sponsorship. If you'd like to sponsor a plaque, drop Sean an email at email@example.com or give him a call at 860-594-0200 and he'll help find a plaque for you.
Dayton Hamvention -- New Products
Array Solutions will be showing a prototype of the new 8-Pakâ¢, a high-isolation 8X2 RF switching matrix that will allow two radios to select from eight antennas. This is a grand updating of the venerable and popular 6-Pakâ¢. It uses a 4-wire interface and the relay box is weatherproof. The company's new dual-port VNA-4180â¢ Vector Network Analyzer extends the model AIM 4170Câ¢ to 120 dB dynamic range and sub-dB resolution for less than $1000. An excellent tool for figuring out how good those filters you built really are (or aren't), or tuning those Field Day stubs right on frequency.
microHAM will be unveiling their USB Interface IIIâ¢ for the first time at Dayton. USB III is a simple, small USB serial interface that includes a USB soundcard optimized specifically for amateur needs. USB III also operates with default system drivers on Macintosh (OS 10.5+) and current LINUX distributions. As such USB III should support any application capable of using "USB Serial" and "USB Sound" devices. Joe W4TV envisions this as a great tool for contest expeditions requiring compact, integrated equipment.
West Mountain Radio will be introducing their new PWRguard that protects the radio, the power supply and the battery from damage. It is an automatic safety switch inserted between a power source and the load. It switches OFF whenever the voltage is over 15 volts or under 11.5 volts. It handles up to 40 amps, and uses an FET as the switch. Other new products will be on display, as well.
Dayton Hamvention -- Contest Content
Contest Super Suite - Wednesday, May 13th through Saturday, May 16th, at the Crowne Plaza hotel beginning at 7 PM each night.
Contest University - Thursday, May 14th
The Contest Super Suite festivities are hosted all or in part by Contest University, Mad River Radio Club, Frankford Radio Club, Potomac Valley Radio Club, and the North Coast Contesters.
50th Anniversary Celebration of CQ World-Wide Multi-Multi Category - Special Celebration Party in the Crowne Plaza's Miami and Beckel Ballrooms at 10:30 PM
May 15, Friday, 2:30 PM - 5:00 PM in Room 1 - Antenna Forum at HARA Arena
May 16, Saturday, 9:15 AM - 11:15 AM in Room 1 - Contest Forum at HARA Arena
17th Annual Dayton Contest Dinner - Saturday, May 16th at 6:30 PM, hosted by North Coast Contesters at the Crowne Plaza
More Hamvention fun -- AMSAT will be producing Satellite Demonstrations outside the Ball Arena Entrance to Hara Auditorium on both Friday and Saturday. There will be a SuitSat-2 hardware demonstration at the AMSAT booth, as well. Stop by and check it out!
In case you're having difficulty communicating the excitement of radio and radiosport, why not let 19-year-old Mark 2EØNCG try? Winner of the Radio Arkala essay contest, he gets the point across quite well! John KC9OQO and Brian WØDZ finished in second and third place, respectively. Argentinian Diego LU8DX was recognized for his submission of the best Spanish language piece.
Another state QSO party returns to life - the 2009 Arizona QSO Party will be sponsored by the ARRL Arizona Section and the Catalina Radio Club on Oct 10th and 11th. (Thanks, Gary KE7DX)
Bob WA1Z is taking over the administration of the Super Check Partial database from Randy, K5ZD. Thanks to Randy for providing the contesting community with top notch support of the SCP database over the last few years. There's now a dedicated email address for submitting logs to the database - firstname.lastname@example.org. Blocked call requests can be submitted to the new email address as well. Bob has the existing blocked calls list, so only new requests are necessary. The next update will be released sometime around September.
Similar to the SCP mentioned above and popular on HF, VHF_USA.ZIP contains a VHF.DTB database consisting of the call signs and grid squares of 12, 242 stations located primarily in Canada, the Caribbean, Mexico, and the USA. A few calls from outside the Western Hemisphere also appear. The Database was formed from Contest Logs for the June, July, September, and January VHF contests provided by stations in all regions of the US and from Ontario. (Thanks, Dave W9ZRX)
KD7PRM, has put together a nice iPhone app called "Maidenhead Converter" for VHF+ contesters needing to manipulate location information. (Thanks, John K7VE)
Buy low, sell high - I guess that works at the solar minimum, too, as the story behind the headline "Oracle Buys Sun" seems to imply.
Web Site of the Week - Fans of the World Radiosport Team Championship were excited to hear the news that the WRTC-2010 Committee's Web site is up and running! Check it out - more details for the competition, to be held in the Moscow area in July 2010, will be posted as they are available! (Thanks, Harry RA3AUU)
WORD TO THE WISE
SIGHTS AND SOUNDS
Bob N6TV found a video of this amazing, fully-automatic keyer that makes both dots and dashes mechanically ("at moderate speeds"), built by WB9LPU. It's probably not iambic, and doesn't have a dot/dash memory, but is still fun to watch.
I think you'll agree that Radioman Ginsburg has that thousand-yard stare of a good Morse operator. (Thanks, Tim K3LR)
Chris W2PA found this nicely categorized Picasa album of QSLs. See any that you recognize?
RESULTS AND RECORDS
The 2008 ARRL SSB Sweepstakes Web version of N2IC's QST article is now online. This writeup includes the ARRL Affiliated Club scores and is a nice complement to VE4XT's article on the CW contest released previously. Take a look at the writeup from the 1930 Sweepstakes and a certificate for the hotly-contested Montana section!
Certificates for the 2008 June VHF QSO Party have all been shipped. Plaques have been ordered and will begin shipping in a few weeks. (Thanks, ARRL Contest Branch Manager, Sean KX9X)
Section records for the June and September ARRL VHF+ contests have been updated through 2008 and put up on the ARRL Contest Branch Web site. (Thanks, Curt K9AKS)
Set that clock! Phil AB7RW/V31RW reports a surprising number of QSL requests coming in with serious time errors. Time errors can cause NIL (Not In Log) results in log checking - or at least complicate the log checking process for your log and that is rarely a good thing. Furthermore, when you upload your log to Logbook Of the World, time misalignment can keep you from getting credit for your QSOs!
TECHNICAL TOPICS AND INFORMATION
"How Much Does Your SWR Cost You" by Stan Gibilisco W1FV, in the January 1979 issue of QST is a classic article showing the effect of SWR on line loss. One of the graphs shows "extra loss" given SWR at the load and transmitter and another shows loss based on SWR at the load and matched-line loss. This is also nicely presented in the Bird Technology Group application note "Cable Loss Masking Effect". Issues of QST prior to 2005 are available on-line to all ARRL members! (Thanks, Paul W9AC and Glen K9STH)
When building sloping dipole arrays such as those described in the ARRL Antenna Book, is it really necessary to switch both conductors of the feed lines? "Absolutely," is the Towertalk reflector consensus! The arrays require that the reflectors not be connected to the driven element in any way. Tying all of the shields together, such as if a common remote RF switch is used, will cause gross pattern distortion from the additional conductors. By using the 3/8-wavelength feed lines and switching both conductors, you will insure that the un-selected dipoles will act as reflectors.
I love the ingenuity and know-how of the ham community. Need to estimate how much cable is on a spool? Try this online calculator courtesy of KG6D, but if you can't acquire the diameter A for that method, N6RK contributes an SWR-analyzer-based method. First, determine the cable's velocity factor with a one-meter piece of cable, attached directly as possible to the analyzer. Find the frequency, f, below 75 MHz at which the meter reads zero ohms. Velocity factor = f / 75. Now measure the spooled cable with an ohmmeter to determine if the inner end is shorted or open. Tune the analyzer to its lowest frequency, then increase frequency until you find an impedance minimum. If the inner end is shorted, this is the frequency at which the cable is Â½-wavelength long and if open, Â¼-wavelength long. Increase frequency until you get to the next impedance minimum. The electrical length of the cable in feet is 492 divided by the difference in the two frequencies. The physical length equals the electrical length multiplied by the velocity factor. (Thanks, Bob N6TV)
Dallas Lankford is well-known in the SWL and BC DXing community - his Web site he has a lot interesting articles on noise reduction receiving antennas for MW and SW. He is mostly an SWL, but the articles are very thoughtful, with a lot of good points. (Thanks, Larry N6NC)
A diplexer allows radios on different bands to use the same antenna - as opposed to a duplexer that enables a receiver and transmitter on the same band to share the antenna. Using a diplexer can be mighty handy on the VHF bands where a log-periodic or discone can easily cover 6 meters through 70 cm (and beyond). George WB2VNV recommends the Austin Antenna diplexers - actually a misnomer, since they make di-, tri-, and even pentaplexers that cover five different bands (28-50, 144, 220, 440 MHz, and 1.2 GHz). One -plexer at each end of a feed line would allow multiple radios to use multiple monoband antennas, too. Just the savings on feed line is substantial.
From the May issue of the Mt Airy VHF Contest Club's "Cheese-Bits" newsletter are references to three seminal Motorola application notes. AN-791 is titled "A Simplified Approach to VHF Power Amplifier Design" and includes a discussion of parasitic effects. AN-267, "Matching Network Designs with Computer Solutions" is a cookbook of matching networks that you can apply to the transistor of your choice. Finally, AN-721 is a detailed treatise on impedance matching, ""Impedance Matching Networks Applied to RF Power Transistors".
Loctite Extend Rust Treatment got a strong endorsement from "Click and Clack - the Tappet Brothers" on the April 29th show so I thought I'd pass that morsel along for the summer painting season.
As a construction electrician with considerable experience in the field, Chuck KI9A recommends a Kellum-type cable grip, with a swivel head, for cable pulls through conduit. Make certain the cables grip fits the wires, without much slack, use some thin tie-wire to help secure it, then, wrap with several wraps of electrical tape. Use liberal amounts of wire lubricant. If you plan on adding anything to the run later, pull a #12 stranded THHN wire in, to use as a pull wire later. Do not use rope or string, as it will chafe and abrade its way into the cables as you pull additional cables later. For the lubricant, Roger K8RI directs us towards "Wire Soap", available at hardware and home improvement stores.
The legendary ham thrift and ingenuity meet in this clever adaptation of a common kitchen sink strainer to antenna ground radial systems, described in this eham.net article.
The Belkin F5C594 cube acts as a line filter with up to 43 dB of suppression at 100 MHz and less at lower frequencies, but still possibly of use in certain circumstances. Other models may offer more filtering and features. (Thanks, Eric VE3GSI)
Bob K6KL contributes this simple example of electricity's power: If all the electrons in a copper penny are separated from their protons and the protons placed on the Moon, a person holding the electrons on Earth would feel a force attractive to the protons of about 400 pounds - enough to lift the person off the Earth and be propelled rapidly to the Moon across a distance of about a quarter-million miles -- by one penny's worth of electrons and protons!
Wooden A-frame towers were a staple of older editions of the ARRL Handbook and the ARRL Antenna Book, but none quite matched the scale of Tesla's 187-foot monsters. These were built for his wireless power experiments! But you don't have to go quite that far. Windmill and water tower designs abound on the Internet for the saw-wielding set. (Thanks, Red WO0W, Bob W5RN, and Brian, KE6IYC)
Why is it called a "Gamma Match"? Because the physical configuration of the gamma match -- a long rod with a perpendicular shorting bar to the element at one end -- resembles a capital gamma in the Greek and Cyrillic alphabets. (Thanks, Jerry K4SAV and Norm W1MO)
If you're building a tower and a leg of that next section is flared just a bit too much, rather than hammer on it, Dave NN5K says, "Use a heavy nylon ratchet strap. Just put it around the section that needs to be squeezed a bit and start cranking on it. When the tension is just right the tower section will slide right on." It works on Rohn 25 through 55 according to Dave.
Oops! Left the SWR Analyzer on and ran the batteries down again? Insert a dummy plug for the external power source into the jack, disabling the internal battery supply. Even if you press the analyzer ON switch by accident it won't turn on until you pull the plug out of the jack. (Thanks, Rob K5UJ)
For reference, so to speak, the units dBd mean "decibels with respect to the maximum gain of a dipole in free space". The last three words are important because if the reference antenna (the dipole) is NOT in free-space, then one must also specify that the antenna whose gain is being compared to the dipole is installed at the same mean height over the same reflecting surface. So "free-space dBd" is a little redundedundant, but it's sometimes important to make sure apples are being compared with apples.
Technical Web Site of the Week - Lots of "I can't find a source for..." questions are answered with a
succinct "try McMASTER-CARR on-line." I'd love to see that warehouse!
Lots of presentations on contesting stress the importance of planning. Plan your operating strategy, sleep time, band changes, and so forth. This is all very well and good, but as the generals know, no plan survives contact with the enemy! So it is with radiosport as the conditions rarely are exactly as expected, the contact rate doesn't make your choices clear and unambiguous, and maybe the equipment gives you an unwelcome surprise or two.
Now what? Pitch the plans out the window and go for it - whatever it is? The best-prepared operators will go to that backup plan, maybe one of several. After all, it should hardly be surprising that circumstances may present you with surprises. As the saying goes, "In theory, theory and practice are the same. In practice, theory and practice are different!"
Where does Plan B come from? It comes from remembering what happened during the last contest and that's why you write down what happened last time - so you'll remember! When the antenna switch developed an open position, what did you do? Would that be a good thing to plan for? The best, of course, is to prevent the problem in the first place with a little preventative maintenance, but given our finite resources, there just might be a failure we don't foresee or forestall.
The problem might not be in the shack - there might be an ionospheric disturbance or maybe an unforeseen sunspot might rotate into view. Either changes the bands and maybe operating strategy. It's a good idea to ask yourself what you would do if the conditions improved or degraded during the weekend. How would you change your operating strategy or sleep time? Would you shift emphasis on the high or low bands? What about changing antenna direction through the day? There are literally hundreds of questions to answer.
I know we have lots of non-contesting readership, as well, that need a Plan B just as much as contesters do, if not more! Every net should have a backup frequency, in case the band is closed or crowded. Never make a schedule without having a second or third frequency and a schedule for using them. And give them a try every once in a while to see if Plan B would actually work! Emcomm groups frequently run exercises using simplex communications - no repeaters - to make sure they can get the job done with little supporting technology.
The real benefit of Plan B however, may not just be in having a backup, but in considering the possibilities of what can go wrong with Plan A! A very useful exercise for project planning is to consider reasons why the project might fail. Certainly, it's important to have confidence that Plan A will work and work well, but a plan that doesn't harden itself against the slings and arrows of everyday life depends on everything being "just right". How often does that happen?
Both populations can mitigate against the need to go to Plan B by reducing the probability of surprises. Contesters can study the bands, propagation forecasts, clean and maintain equipment, and so forth. A problem found and fixed before the contest is that many more points in your pocket! The non-contester can avail themselves of propagation forecasts, too, as well as the numerous on-line contest calendars that provide plenty of warning about band loading in the future. After all, not planning for solar disturbances that occur on 27-day intervals or being surprised by a contest that's run on the first weekend of a month for more than 50 years...well, maybe Plan A needed a little polishing.
I really hate those maddening "surprises" that make hash out of my careful plans, but Mother Nature and Mister Murphy work hand-in-hand to keep me on my toes. The only defense I have is preparation and Plan B. How about you?
An expanded, downloadable version of QST's Contest Corral in PDF format is available. Check the sponsor's Web site for information on operating time restrictions and other instructions.
EU PSK DX Contest--Digital, from May 16, 1200Z to May 17, 1200Z. Bands (MHz): 3.5-28. Exchange: RST and EU area code or serial. Logs due: 28 days. Rules
His Majesty King of Spain Contest--CW, from May 16, 1200Z to May 17, 1200Z. Bands (MHz): 1.8-28. Exchange: RST and serial or EA province. Logs due: May 19. Rules
All America Contest--CW, from May 16, 1500Z to May 17, 2359Z. Bands (MHz): 3.5-28. Exchange: RST, continent, and category. Logs due: Jul 30. Rules
Baltic Contest--Phone,CW, from May 16, 2100Z to May 17, 0200Z. Bands (MHz): 3.5. Exchange: RS(T) and serial. Logs due: Jul 1. Rules
Worked All Britain - LF Phone, from May 17, 1000Z to May 17, 1400Z. Bands (MHz): 1.8-7. Exchange: RS, serial, and WAB nr or DXCC entity. Logs due: 21 days. Rules
Bill Windle QSO Party--CW, from May 23, 0000Z to May 23, 2359Z. Bands (MHz): 1.8-28, 50,144, Frequencies: 15 to 40 kHz above band edge. Exchange: RST, name, FOC number. Logs due: Jun 7. Rules
MI QRP Memorial Day CW Sprint--CW, from May 25, 2300Z to May 26, 0300Z. Bands (MHz): 1.8-28. Exchange: RST, S/P/C, MI QRP number or power. Logs due: 30 days. Rules
Bill Windle QSO Party--CW, from May 23, 0000Z to May 23, 2359Z. Bands (MHz): 1.8-28, 50,144, Frequencies: 15 to 40 kHz above band edge. Exchange: RST, name, FOC number. Logs due: Jun 7. Rules
LOG DUE DATES
13 May to 26 May
May 13 - Low Power Spring Sprint, email logs to: email@example.com, paper logs and diskettes Radioklub OM3KFV, P.O.Box 3, 038 61 Vrutky, Slovakia. Rules
May 13 - Araucaria VHF Contest, email logs to: firstname.lastname@example.org, paper logs and diskettes (none). Rules http://www.avhfc.com/rules/avhfc_ee.pdf, May 15 - Georgia QSO Party, email logs to: email@example.com, paper logs and diskettes John Laney, K4BAI, PO Box 421, Columbus, GA 31902-0421, USA. Rules
May 15 - SKCC Weekend Sprint, post log summary at: http://www.skccgroup.com/sprint/wes/wes-submit.html, paper logs and diskettes (none). Rules
May 16 - TARA Skirmish Digital Prefix Contest, email logs to: (none), post log summary at: http://n2ty.org/seasons/tara_dpx_score.html, paper logs and diskettes (none). Rules
May 18 - Michigan QSO Party, email logs to: firstname.lastname@example.org, paper logs and diskettes Mad River Radio Club, c/o Dave Pruett, 2727 Harris Road, Ypsilanti, MI 48198, USA. Rules
May 18 - 10-10 Int. Spring Contest, CW, email logs to: email@example.com, paper logs and diskettes Dan Morris, KZ3T, 131 Valencia Lane, Statesville, NC 28625, USA. Rules
May 18 - 10-10 Int. Spring Contest, Digital, email logs to: firstname.lastname@example.org, paper logs and diskettes Dan Morris, KZ3T, 131 Valencia Lane, Statesville, NC 28625, USA. Rules
May 18 - Microwave Spring Sprint, email logs to: email@example.com, paper logs and diskettes 2009 Spring Sprints, c/o Chuck Towner, W9KQJ, PO BOX 73, PALATINE, IL 60078-0073, USA. Rules
May 19 - ARLHS Annual Spring Lites QSO Party, email logs to: (none), paper logs and diskettes Dave Ruch, NF0J, P.O. Box 20696, Bloomington, MN 55420-0696, USA. Rules
May 19 - EA-QRP CW Contest, email logs to: firstname.lastname@example.org, paper logs and diskettes Vocalia de concursos (Concurso CW), PO Box 17, E-16080, Cuenca, Spain. Rules
May 19 - YU DX Contest, email logs to: email@example.com, paper logs and diskettes Savez Radio-amatera Srbije, YU DX Contest, P.O. Box 48, 11001 BEOGRAD, Serbia. Rules
May 20 - ES Open HF Championship, email logs to: firstname.lastname@example.org, paper logs and diskettes Toomas Soomets, ES5RY, P O Box 177, Tartu 50002, Estonia. Rules
May 26 - Florida QSO Party, email logs to: email@example.com, paper logs and diskettes Florida QSO Party, c/o Ron Wetjen, WD4AHZ, 5362 Castleman Dr., Sarasota, FL 34232, USA. Rules
May 26 - 50 MHz Spring Sprint, email logs to: firstname.lastname@example.org, paper logs and diskettes 2009 Spring Sprints, c/o Chuck Towner, W9KQJ, PO BOX 73, PALATINE, IL 60078-0073, USA. Rules
May 26 - SP DX RTTY Contest, email logs to: email@example.com, paper logs and diskettes (none). Rules