AmateurRadio.com

It's time once again for The Weekender. This is our bi-weekly departure into the world of amateur radio contests, open source conventions, special events, listener challenges, hedonism and just plain fun. Thanks for listening and, if you happen to get a chance, feel free to call us or e-mail and send us some feedback. Tell us how we're doing. We'd love to hear from you.

73 de The LHS Crew

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].

Hello and welcome to the 460th episode of Linux in the Ham Shack. In this short-topics episode the hosts discuss the RaDAR Challenge, the ARRL.org website redesign, secure deleting of files in Linux, new distros from Debian, Ubuntu and Fedora, contributing to open source and much more. Thank you for listening and have a great week.

73 de The LHS Crew

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].

In this episode, Colin Butler (M6BOY) is joined by Edmund Spicer M0MNG, Ed Durrant DD5LP, Dan Romanchik KB6NU and Leslie Butterfield (G0CIB) to discuss the latest Amateur / Ham Radio news. Colin (M6BOY) rounds up the news in brief and in the episode's feature Hamzilla 2022

We would like to thank Bradford Whiting (kd7gdt) and our monthly and annual subscription donors for keeping the podcast advert free. To donate, please visit - http://www.icqpodcast.com/donate

• ARRL Teachers Institute to Offer Four Sessions this Summer
• Russia and Belarus Suspended from CEPT membership
• Australian Radio Hams Help out after Floods
• AMSAT Receives a Grant From ARDC
• RSGB National Radio Centre re-opens
• International HEMA Day
• RSGB Announce Resignation of Board Director

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

One of the most valuable tools for amateurs worldwide to use when evaluating HF rigs is the set of bench tests that Rob Sherwood NC0B has provided for quite a number of years now. He ranks the receive tests by his favorite metric: narrow dynamic range in dB. It’s a key for CW contest operators (pun intended) which he is in spades. But it is a frequent question from readers of Rob’s table: why can’t I sort it on another criterion? Especially if I’m not a CW contest operator?

Well, now you can! Working directly with Rob NC0B, I’ve taken his latest receive test data and made a sortable table for the Sherwood Test Results. They are circa March 5, 2022. It’s at my companion site, foxmikehotel.com at this link. I plan to update it when Rob adds new radios to his Table.

I’ve also added sub-pages to illustrate some facets of the data. Based on my work over the past couple of years with adding price and consumer satisfaction data for each rig in his Table, I’ve learned that it’s important for readers to better understand both Rob’s tests and his ranking metric. In that research published in the ARRL’s National Contesting Journal, I created a composite of all nine of Rob’s bench tests which I called the Sherwood Performance Index (SPI). It is a broader assessment of receive performance than the narrow dynamic range. But it is not intended to be a replacement for Rob’s preferred metric, only a complement.

Thus far, I’ve added two interactive charts that will help the viewer better understand Rob’s table results. More may come.

One chart shows how the reader can “out-rank” themselves by ONLY focusing on how a rig is ranked on the narrow dynamic range measurement. Rob tells readers not to take the exact ranking as the only aspect of a rig for the top ten rigs are all very good on receive. This interactive graphic will allow the viewer to see how some rigs “bunch” together with almost identical narrow dynamic range but are, indeed, sequential ranked because of numerical differences that simply do not make much difference as realized in the rig’s actual performance. But, ever hear an athletic team cheer this after a game? We’re Number 10! We’re Number 10! I didn’t think so. But Number 10 might be just as good as Number 1 on the metric determining the ranking. You have to look at the data behind the ranking. This chart makes it easy.

A second chart demonstrates how Rob’s ranking variable, narrow dynamic range, relates to the composite SPI. You’ll find some interesting results from that chart, seeing how narrow dynamic range is important but there is more to some rigs than that. Especially if you’re not a contest operator, CW or otherwise.

As he has stated in various podcast interviews (including mine on the ICQ Podcast and recently on the Ham Radio Workbench), he started these bench tests for his own use as a CW contest operator. Rob disagreed with the ARRL’s tests as published in a review of the classic Drake R-4C receiver. So he created what he thought was a suite of appropriate bench tests. And the rest is history. For transceivers and receivers (“rigs”) over a 50 year period!

Here’s a trend line for the SPI by year over the horizon of rigs in his Table, circa November 2019. We are in the best period yet for receive performance in terms of Rob’s test suite. But now you can sort the Sherwood Table on any of his tests including the composite SPI that I added to asses your rig of choice.

Rob codes his website in conventional HTML. He recently had to suddenly change hosting providers. So he’s had enough on his plate with all of the other engineering contributions he makes almost daily to various email lists and groups. So while he could alter the HTML code to provide the ability to sort his table, I appreciate his spending his retirement time continuing to assist the amateur radio community as he does now. I hope that this offering of a Sortable Sherwood Table on my companion website will help the reader better understand this terrific tool as well as help Rob, too.

Frank Howell, K4FMH, is a regular contributor to AmateurRadio.com and writes from Mississippi, USA. Contact him at [email protected].

It's time once again for The Weekender. This is our bi-weekly departure into the world of amateur radio contests, open source conventions, special events, listener challenges, hedonism and just plain fun. Thanks for listening and, if you happen to get a chance, feel free to call us or e-mail and send us some feedback. Tell us how we're doing. We'd love to hear from you.

73 de The LHS Crew

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].

AmateurLogic.TV Episode 167 is now available for download.

George explores a Jameco Electonics Grab Bag. Mike installs Dragon OS Pi 64. Tom Apalenek, WA2IVD visits Quartzfest 2022. Tommy reviews the B3606 Power Controller. Importance of ESR in Capacitor Testing.

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George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at [email protected].

When doing VHF activations for Summits On The Air (SOTA), the radio range is dependent on the height of the summit and the surrounding terrain. The Radio Mobile website from Roger/VE2DBE is a great tool that can be used to estimate the radio range from a particular site. Repeater system owners often use tools like this to predict the coverage of their repeaters. I don’t normally do this type of analysis for SOTA…I just look at a topo map and get a rough idea of how far my signal will go. Then, I decided to spend a little time analyzing a few summits in Colorado to see what I could learn.

Pikes Peak (W0C/FR-004)

Pikes is a 14,115-foot summit that towers over the eastern plains of Colorado, making it an ideal radio site. The Radio Mobile plot shown below shows the solid radio coverage in blue and the fringe area in yellow. I won’t go into how to use Radio Mobile on this post. As you’d expect, you enter the location of the radio site (summit) along with various parameters such as frequency, minimum detectable signal level, transmit power, and antenna gain. I entered some nominal parameters consistent with typical SOTA stations on 146 MHz (2 meters).

Pikes covers about half of the state of Colorado, reaching out to the Kansas state line. To the west, the coverage does not go as far because the radio signals are blocked by other mountain ranges. In particular, the signal tends to drop off at the Sawatch Range, west of Buena Vista. I’ve activated Pikes many times and this plot lines up well with my general experience. The blue area can be worked quite reliably with a decent station on both ends. By “decent” I mean a 20-watt transmitter on the summit with a small Yagi antenna and a 40-watt radio with an omnidirectional antenna at the chaser station. Working stations near the Kansas state line is usually easy on 2m FM. The highest spot in Kansas (Mount Sunflower, not a SOTA summit) can usually be worked without much trouble. However, longer distance contacts are possible, especially using SSB or CW. I’ve written before about the Myth of VHF Line-Of-Sight.

When using VHF for SOTA activations, It is important to consider the potential stations that will be within range and on the air for you to work. Besides being a high summit, Pikes overlooks the major cities in Colorado, from Fort Collins to Pueblo, so finding someone to work on 146.52 MHz is usually easy. It is common to have a pile up of stations calling you.

Colorado has over fifty 14,000-foot mountains and all those are workable from Pikes Peak on 2m FM.

Mt Herman (W0C/FR-063)

Mt Herman is another popular SOTA summit, with an elevation of 9063 feet, not nearly as high as Pikes Peak. This summit also looks out over the eastern plains of Colorado, as shown in the coverage plot below. Although the range is not as good as Pikes, it still covers the major cities, so again it is easy to do a 2m FM activation from Mt Herman. It is more difficult to work stations to the west. I can usually work stations in Woodland Park and Divide from Mt Herman, but reaching Buena Vista is a challenge.

Threemile Mountain (W0C/SP-107)

VHF activations can be much more challenging when the summit is further away from populated areas. Let’s consider Threemile Mountain, which is 10,020 feet in elevation, located about 20 miles south of Hartsel, CO. This summit tends to get blocked to the east by the Front Range and to the west by the Sawatch Range. Even though the summit is higher than Mt Herman, its radio range is not as good.

In particular, it does not cover Denver, Colorado Springs, and Pueblo very well, so the number of available stations to work drops dramatically. There are a number of stations that monitor 146.52 MHz up in the mountains, so if you are patient you can usually make some VHF contacts. This can be a source of frustration for VHF activators, or you can take it on as a challenge.  I have activated Threemile five times and I don’t think I’ve ever worked a Denver station on 2m FM. I have worked some Denver stations from there using 2m SSB, during a VHF contest. Oh, I did manage to work Larry/N0LL in Smith Center, KS on 2m SSB for a distance of 372 miles. See Radio Fun on Threemile Mountain (W0C/SP-107). So you never know what you’re going to get on VHF/UHF.

Conclusions

So what conclusions can we draw from this analysis?

1. Radio Mobile does a good job of predicting typical 2m FM coverage. My experience on these summits aligns well with the Radio Mobile predictions.
2. But much longer distance contacts are still possible. VHF is not limited to line of sight. Radio Mobile is intended to predict reliable radio coverage, not the exceptional radio contact.
3. Be aware of the population density of the coverage area because that is a huge factor for making radio contacts. New VHF activators should start on summits that overlook the major Colorado cities.
4. Improve your VHF activator station. Every additional dB of signal improves your ability to make those weak-signal contacts on the edge of the coverage area.

As always, get off the couch, gather your radio gear, and head for a summit.

73 Bob K0NR

The post VHF Range From SOTA Summits appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to AmateurRadio.com and writes from Colorado, USA. Contact him at [email protected].