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Best of the ARRL Contest Update Since Dayton 2011 Ward Silver NØAX, Editor

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Best of the ARRL Contest Update Since Dayton 2011 Ward Silver NØAX, Editor Best of the ARRL Contest Update since Dayton 2011 Ward Silver NØAX, Editor The following is a potpourri of contester-friendly tidbits gleaned from ARRL Contest Update issues since the 2011 Dayton Hamvention. The newsletter is free to ARRL members – just log on to the ARRL website and edit your membership information to add the Contest Update to your list of newsletters and bulletins. 25,000 readers can’t be wrong! This great three-part series on impedance matching was published by Lou Frenzel W5LEF in Electronic Design magazine. Part 1, Part 2, Part 3. (Thanks, Al AB2ZY) Mike WØBTU has created an informative web page on Beverage antennas - especially how to build and control a two-wire Beverage. A reminder - asking to be spotted is considered "self-spotting" and is specifically not allowed in nearly all contests. The documentation on K2AV's Folded Counterpoise Antenna (FCA) contain a lot of good information. Take a look around the WØUCE web site for more! Jim AD1C has released version 3.1 of PASS - a program to analyze passing stations from band-to-band during contests. This version includes pass_win.exe which will work from a command prompt under Window 7/Vista as well as Windows XP. Brian K1LI writes, "In the category of "useful resources," I find that the Space Weather Alerts and Warnings Timeline gives me, at a glance, lots of information that helps me understand what's going on propagation-wise, such as the timeline for Jan 16 -31. It gives a very interesting depiction of the events we all witnessed.” If you aren't getting the ARRL Propagation Bulletin by Tad K7RA, there is a lot more to it than just solar indices. Tad spices up the discussion with background on solar events, stories from readers, and great links to online resources. Log into the ARRL web site and click "Edit Your Profile" - you'll find the bulletin on the "Edit Email Subscriptions" tab. The website Amanogawa has many nice online electromagnetic engineering Java applets that open in separate windows for circuits, antennas, transmission lines, EMC/EMI, and a very interesting Smith Chart tutorial. This week's handy map gadget was contributed by Bob N6TV who located this interactive topo map that offers features useful to hams scouting out QTHs and antenna locations. Not only does the map tell you the elevation, it tells you the slope angle and slope direction of US locations, as well. The late G4FGQ created a number of useful calculator utility programs such as this radial calculator that includes the conductivity of the soil. With it you can begin to answer the question, "How many ground mounted radials do I need and how long do they need to be?" All such calculators are a model and probably deviate from an exact simulation but you can get an idea of what might work. Another tack is to vary the radial length but keep the number of radials constant. (Thanks, Bob N6TV) Todd KC9BQA has made several new web posts to that are helpful to newer VHF+ contesters, such as the articles titled VHF Contesting School. The articles are broken down into bite-sized pieces geared toward getting a novice VHF+ operator comfortable calling "CQ Contest". With the CQ 160 contests coming up shortly, here's a simple receive antenna recommended by Tim K3LR. The VE3DO loop is also straightforward to build and install, making it a good "temporary" antenna. John G3JVC/GM3JVC recommends a useful publication for your bookshelf on fighting EMI developed by the US Naval Postgraduate School, "The Mitigation of Radio Noise From External Sources at Receiving Sites". It's a tour-de-force on problems hams know well. The Internet Archive project has just published nearly every issue of defunct 73 magazine, all the way back to January 1961. While dominated by the editorial adventures of Wayne Green W2NSD, the magazine also featured loads of simple (sometimes too-simple) construction articles, expedition adventure writing by Gus Browning W4BPD and others, and had a loyal following for many years. You may read the material online or download PDF files. (Thanks Leigh WA5ZNU via the QRZ.com website) If you answer a CQing station and they respond with an error in your call, the most reliable way to be sure they have your call correct is to send only your call sign again and not the exchange. Don't send the exchange until the CQer responds with your correct call - then send your exchange. Mike K5WMG has written and published a good paper illustrating the effects of height-above-ground on vertical takeoff angle for beam antennas. It shows why a good "first tower" height of 50 feet works well and why higher performance antennas need that extra vertical "oomph". Kirk K4RO found this nice video about building Beverage antenna transformers. I especially like the "mount on lid, not box" idea. Sometimes finding the right person to answer questions at the local power company is more difficult than the 80th section near the end of Sweepstakes! In the meantime, complete documentation and all sorts of valuable guying information and soil information can be found at the AB Chance civil construction web pages. (Thanks, Tom N4NW) If you live in a location where ice can build up on your guy wires, watch out for melting ice sliding down into the Preform Big Grips - they can be knocked loose by a big enough impact! Dave W6NL suggests placing a small hose clamp around the end of the grip - this prevents the grip from loosening due to an impact. Voice maintenance - to keep your voice in good shape during a long contest, learn to speak clearly at a comfortable level without shouting. It helps to practice with a friend on the air in setting your mic gain and compression levels properly. If you use voice recordings, take steps to reduce the amount of background noise in them and try to match your normal speaking voice settings for clean transmitted signals. (And watch that VFO frequency when clicking on a spot - it's easy to not notice that the frequency is outside your operating privileges or too close to a band edge.) If you know what cables will be in a run of conduit, an alternative to pulling them through the finished run is to lay them out next to the trenches and slide the conduit sections into place over the cables. Then glue the sections together as you lay them into the trenches. You can include a pull rope in to the bundle for future use. Make sure the conduit joint surfaces are completely clean before gluing. This might not be practical for very long runs of conduit, though. (Thanks, Alan K9MBQ) Pat WW9R contributes this tip for computer logging - "I find it helpful to run a strip of masking tape above the Function keys and mark what each one does. Then, in the heat of the battle or when you get really tired, you can find all the messages! I fill all available CW messages with something like "73""GL" "?" "AGN" and the individual parts of the exchange; sometimes a slowed-down version of the exchange so I don't need to touch the CW speed setting." Tektronix veteran, Don W7WLL recommends the YouTube videos by W2AEW as really good tutorials on using an oscilloscope for ham radio measurements. He also has an excellent video at the same site titled "Scopes For Dopes" - it is an excellent tutorial for those who are daunted by the oscilloscope. Read the rules BEFORE the contest, runic though they may be! How much off-time and how long are the breaks? Where are the power limits set? Can single-ops use the spotting networks? Don't embarrass yourself by having to back-track after the contest, submitting in a category you didn't know you had entered! Tower climbing pro, Dan K1TO, points out that thrust bearing bolts are not designed to support a heavy mast as described in the previous issue. The way to do this properly is to have at least one muffler clamp with a saddle (or better yet, two saddles with through bolts) tightened securely to prevent any downward slippage of the mast while moving the rope attachment point. When installing antennas on a mast, don't forget to leave a "rotator loop" in the feed lines to allow the antennas to turn without pulling on the cables! As Steve K7LXC points out, "There are two rotator loop methods. One has the cable(s) coming off the mast with 5-6 extra feet to just hang off the tower and follows the mast around as it turns. The other way is to loop the cable(s) 2-3 times around the bottom of the mast at the flat top of the tower 2-3 times. The cables sit on the tower top and allow lots of rotation. Either way works Fine Business." Thanks to K6TD, the Cabrillo Statistics program originally developed by K5KA (SK) and now maintained by Bob N6TV, has just been ported to the Mac OS X environment. This program generates hour-by-hour rate sheets and valuable SO2R statistics from a Cabrillo-formatted file. It creates a simple text file that can easily be pasted into a reflector post. You may now download CBS version 10e for Windows, Mac OS X, and Linux. CBS Version 10e adds new support for NAQP-RTTY and CQ-WW- RTTY logs, as well as a number of bug fixes and minor improvements. This is a simple command line utility written entirely in C and is small enough to download from a slow dial-up connection (<100 kbytes).
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