Topband: WWDXC Top-Band Anthology
Hi all, Interesting that these should pop up again after so many years! They were published in 1998 and 1999, IIRC. I don't have the electronic files on my current system. They may be on floppies upstairs in a box somewhere :-) Unlikely that they are in PDF format but maybe. I'll eventually get a chance to look and see what is stashed away. At any rate, neither volume (there were two) is currently available. 73, Ward N0AX _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: New Top Band and VHF Contesting Authors
I'm glad to let everybody know we have a new author for the ARRL 160 Contest writeup. Mark Beckwith N5OT has stepped into the ample shoes of outgoing author, Gary Breed K9AY whose writeups we enjoyed for a number of years. Hats off to both gentlemen! I know we'll continue to hear K9AY on Top Band - have some fun, Gary! On the very-short-waves end of things, Ralph "Gator" Bowen N5RZ is replacing Jeff Klein K1TEO for the ARRL September VHF Contest. Jeff had been thinking about retiring from being the author for a while and now has his hands full dealing with the loss of a tower and a bunch of antennas from high winds just before the Hamvention. We'll miss him on the bands and in the authors roster, both. Gator, we are looking forward to the Texas perspective on this fall's contest. Extending the run of new authors, Bob Striegl K2DRH has schedule conflicts and needs to give up his post as the author of the June VHF Contest, coming up next weekend. We have an offer of assistance from long-time active contester, Tim Marek K7XC, to provide some research and statistics to whoever takes the reins as lead author. But we do need a new lead author - if you'd like to give the writeup a try, drop me or ARRL Contest Branch Manager, Bart Jahnke W9JJ (w...@arrl.org) a note to learn about the specifics. There are lots of resources for you and you'll acquire a new appreciation of the contest. Thanks to all of the volunteers and "friends of contesting" who keep the wheels going in the ARRL Contest Program. With more than a dozen unique contests, it takes a lot of shoulders to that wheel and a lot of goodwill. See you on the bands! 73, Ward N0AX ARRL Contributing Editor _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: ARRL 160
If the web upload app for log submission finds something in a QSO: line it can't deal with... > The ARRL submission AP tells you to correct the mistakes rather than remove or unclaim them and that is NOT RIGHT! Point of clarification - the app does not really know anything about a particular call. It just knows that the data it found in what it thought was a call sign field did not look like a call sign. (You would get a similar error if the Sent Call data is bad or the RST isn't an RST.) It is up to the log submitter as to what to do about that. If the QSO: line is just mis-formatted, rearranging the information to satisfy the Cabrillo format is perfectly OK. If the call sign is busted (from typo, mis-copy, or whatever), my suggestion would be to remove the line entirely. Same thing if the the section abbreviation is not valid. 73, Ward N0AX _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Clean Sweeps in ARRL 160
Yeah - manual but doable. There are a lot of obviously wrong entries there - like "97" sections. Probably a typo or sections + entities. I'm looking for "83" :-) 73, Ward N0AX On 12/4/2016 4:54 PM, Mark K3MSB wrote: 3830 Scores -> Contest Summaries is one source, but it's not official http://3830scores.com/listeditions.php?arg=B6cgaWz5a3 73 Mark K3MSB On Dec 4, 2016 4:17 PM, "Ward Silver" <hward...@gmail.com <mailto:hward...@gmail.com>> wrote: Not by me, I assure you, but several have been reported after this weekend's excellent conditions. Does anyone know of historical clean sweeps of all ARRL/RAC sections in any prior ARRL 160 contests? The online score database only lists "mults" which include both sections and DXCC entities. 73, Ward N0AX _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Clean Sweeps in ARRL 160
Not by me, I assure you, but several have been reported after this weekend's excellent conditions. Does anyone know of historical clean sweeps of all ARRL/RAC sections in any prior ARRL 160 contests? The online score database only lists "mults" which include both sections and DXCC entities. 73, Ward N0AX _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: ADC Overload
Perhaps an alternative analogy would be helpful here... Each of the many signals can be imagined as its own phasor. One end of the phasor is anchored on the origin (0 V) and the other is spinning around the origin at the frequency of the signal with a length equal to its amplitude. Since the ADC responds to instantaneous voltage, what matters is the vector sum of all those many phasors. A large number of the phasors must align perfectly to add up to extreme voltages that overload the ADC. As you might imagine, this happens very, very rarely under most circumstances. Even when it does happen, it only happens for a fleeting instant because of the semi-random phase and frequency relationships between the phasors. Thus, Jim's bell curve in which the extreme voltage probability is very low. One caution about circumstances: if there are truly large signals present (such as at a multi-multi station or near an AM or SW broadcast station) many fewer phasors must align to create the overload voltage and so the overload happens more frequently. Still, the alignment is quite brief and after the raw sample set is decimated, overloads lasting for just a few samples or less don't have a lot of effect. 73, Ward N0AX On 10/14/2015 11:00 AM, topband-requ...@contesting.com wrote: My example considered an SDR transceiver that received two signals, each with instantaneous RF voltage that varied from +3V to -3V, and for simplicity I assumed each signal could have only seven values spanning this range. I didn't make it clear that these are independent signals on different frequencies. Thus every time the ADC in an SDR samples the voltage sum of the two signals at its input, it will get a different result. For example, with one sample the SDR may see a voltage of +1V, which comes from +2V from one signal and -1V from the other signal. A later sample might produce a voltage of -2V, which could come from +1V from one signal and -3V from the other. In other words, with each sample, the SDR will measure a different voltage, because the signals have different frequencies and are not in phase with each other. Suppose now that we let the SDR sample the voltage a million times, one after another. Then the Central Limit Theorem tells us how those million measurements will be distributed, in other words how many times the SDR will measure 6V, 5V, 4V...0...-4V,-5V,and -6V. What the CLT tells us is that the distribution of these measurements generally follow a bell-shaped curve, with the peak at 0V. This means that most of the time, the SDR will measure approximately 0V at its input. Only infrequently will it measure the large +6V and -6V voltages, because those large voltages are at the extreme edges of the bell-shaped distribution. _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Missing Contest Listings - Contest Update for 19 Dec
An unfortunate cut-and-paste misfire resulted in omitting the RAC Winter Contest and Stew Perry TBDC contests from the lists of upcoming events - I've corrected the online version. The ARRL Letter should have the correct information when it goes out later this week - apologies. 73, Ward N0AX Mis-editor, ARRL Contest Update ___ It is undesirable to believe a proposition when there is no ground whatsoever for supposing it is true. - Bertrand Russell
Topband: ARRL 160 and Other Inequities
I concur with Tree that it is a good thing having three quite different 160 meter contests in the space of two months (ARRL, Stew, CQ WW) and the ARRL DX Contest if you want to do it as a single-band entry. The scoring is different because all of them have different missions. I also recognize that there are significant inequities in the scoring. This makes it hard for disadvantaged areas to be noticed because the writeup authors, of necessity, have to focus on the overall competition. What is the solution, short of changing the scoring in pursuit of the elusive level playing field? Why not add some regional reporting as we have done for the ARRL DX Phone and, on occasion for the ARRL DX CW? There are plenty of people out there who have enough experience on the band to look at the scores in their areas and come up with a good summary. This won't change the overall Top Ten but it can go a long way to recognizing excellent efforts. The ARRL has defined several regions (see any recent major ARRL contest extended writeup at www.arrl.org/contests) that could be used as the basis for such a report. I can't speak for CQ or the Boring ARC but as the managing editor for ARRL contest writeups who works with each author, I can assure you that we have room on the web for regional coverage and would welcome it in any of the ARRL contests. Drop me a note about your region of interest and I'll explain the general process. 73, Ward N0AX ___ Topband reflector - topband@contesting.com
Re: Topband: HFTA, Radio Arcala, general comments
My comments?follow on three topics that have been brought up, ? HFTA - It can import?the elevation angle files generated from IONCAP/VOACAP that Dean N6BV produced. HFTA?does not have an ionospheric module in it. And yes, the files only go down to?80m because of IONCAP/VOACAP limitations. ? Radio Arcala - I have always believed that a horizontal antenna on 160m at very high latitudes would?generally be worse (note that I didn't say always)?than a vertical due to the effect of the Earth's magnetic field. How?theory translates to the real world is always subject to careful consideration, but I've seen enough data in the technical literature to stand by my belief. ? Propagation on 160m - This is a very difficult topic. Most of what makes 160m go is down at D region and E region altitudes, and it is very tough to gather data on these regions at night. What data we have is mostly from rocket flights and scatter radar - which gives us a model that probably doesn't capture all the? variability.?And I don't think we know all the mechanisms yet that give us good propagation versus bad propagation. ? Carl K9LA Bob Brown NM7M (SK) wrote lots about propagation being quite a bit different on 160 and MF because the ionosphere does not interact with the waves in the same way it does at HF. The electron gyrofrequency (I just *love* saying gyrofrequency, don't you?) in the lower layers (what Carl is referring to above) is much closer to 1.8 MHz and causes the wave coupling to change dramatically in ways that are not well understood. This changes with latitude and time of day (or night). There were a number of articles by Bob about ducts between the layers that were very dependent on wave launch angle to get into them. Such effects lead to odd propagation like the frequently observed spotlight propagation and the high-angle antennas hearing and working DX signals when low-angle would seem to be what should work better. My point is that applying models of ionospheric propagation that work at HF, even 80 meters, often have a lot of trouble at lower frequencies because the physics are different at those frequencies. That means you might need a different approach to antenna system design than you would find successful at higher frequencies. Things like improving system efficiency give the same benefits but the most desirable antenna radiation pattern may not be what you expect. Consequently, this is an area in which amateurs truly can push the state of the art. 73, Ward N0AX ___ Topband reflector - topband@contesting.com
