On August 18, I activated Mount Peck (W0C/ SP-053) with Steve/K5SJC, which put me over the top of 2000 activation points for SOTA. This is commonly known as 2x Mountain Goat or Double Mountain Goat. (Joyce/K0JJW was out of town, leaving me unsupervised for a few weeks.)

Steve, thanks for doing Mt Peck with me, it was fun! Joyce and I had great fun activating it back in 2017, and it was good to return to it. The summit is near the Continental Divide Trail, accessed from Monarch Pass, so it is an excellent hike on top of the world. The coolest thing about this summit is the nice rock that served as a gear table (see Steve’s photo above.) No bending down to pick up my backpack or equipment.

I tend to see the Mountain Goat Award (1000 points) as the primary SOTA award, establishing the SOTA activator as serious about the program. Anything beyond that is just more points. But still, 2000 points is a milestone worth recognizing, and it caused me to examine my SOTA log in retrospect.

Here are my stats for SOTA activations:Thanks to all of the chasers who made these activations possible. Here are my top chasers:

Here are some fun facts I have from reviewing my log. Currently, I have 2005 activation points. If you ask the SOTAdatabase for my 2m log, it also shows 2005 activation points. This is not quite right in my view, because it counts all activations with points that have at least one 2m contact included. That is, not all activations had four 2m or VHF contacts. In reality, I have 9 activations (corresponding to 41 points) that used HF to get the required four QSOs (for points). This means I need 36 more 2m-only points to get a pure 2x VHF Mountain Goat, untainted by HF QSOs.

People wonder how often Joyce/K0JJW and I get skunked on a summit using only VHF. Out of 346 activations, I’ve had 20 times falling short of getting the minimum four QSOs (5.7% of the total). I basically never fail to activate a summit because Joyce is usually along, and we work each other (outside the activation zone) to qualify for the activation, but not the points. Sometimes we anticipate that a VHF-only strategy is going to be a problem, so we take along HF gear to make up the difference. This usually happens in a rural area with low population density or in some other remote location such as American Samoa (KH8). Sometimes, we’ve made an extra effort to arrange for capable VHF stations to chase us. Good examples of this are Mount Ojibway and Capulin Mountain. Finally, sometimes we just accept the likelihood that we will come up short on VHF, but do the VHF-only activation anyway.

I’ve written a lot about how to optimize your VHF SOTA activations on my blog. In particular, see The Truth About VHF SOTA. SOTA is a fantastic and versatile program that can be adapted to your particular interests. Keep having fun with your kind of SOTA, whatever that is!

Special thanks to my spouse, hiking partner, SOTA enthusiast, and favorite radio amateur, Joyce/K0JJW, for joining me on these many SOTA activations.

73 Bob K0NR

The post Another SOTA Milestone: 2x Mountain Goat appeared first on The KØNR Radio Site.

I’ve been having fun with mountaintop VHF ham radio for decades, way before Summits On The Air (SOTA) was a thing. It is an activity that I enjoy very much during VHF contests, Parks On The Air (POTA) activations, SOTA activations, and just goofing around in the mountains. Most of this activity has been on the 2-meter band, but any frequency above 50 MHz can be fun.

My philosophy with ham radio is to have fun doing ham radio things and tell people about it. If they think VHF SOTA looks like fun, other hams may try it. At the same time, I want to be open about the challenges that may be encountered. Doing SOTA activations using just VHF can be difficult, even frustrating. (This is one of the reasons I like doing it.) So this post is a cautionary tale, focused on three essential principles.

1. VHF SOTA is easy to do, except when it’s not

A VHF SOTA activation can be as simple as taking a $30 handheld radio on a hike up a summit and making a few contacts on 146.52 MHz or another simplex frequency. The radio is compact, lightweight, and completely self-contained, ready to go! This is arguably the easiest way to do a SOTA activation if the summit is near a populated area.  For example, Genesee Mountain (W0C/FR-194) at 8284 feet overlooks the greater Denver area, so hike to that summit and you should have plenty of stations to work on 2m FM.

Now, try that same approach in a more rural part of the state and you may run into trouble. This is when VHF SOTA is challenging and potentially frustrating.

Which leads us to the second important principle…

2. You need to have chasers within range to contact

This is obvious, but you do need stations that are within range to work. This becomes more difficult in areas that have low population density. There may not be many radio hams within range of your chosen summit; they may not have 2m FM gear, they may not be listening to your frequency, and they may not even have the radio turned on.

Before activating a summit, consider the likely range and how many chasers might be around for you to contact. Take, for example, Aspen Ridge (W0C/SP-084) on the west side of South Park. The hike up is easy, and the elevation is substantial at 10,740 feet. The map shown above has a circle with a radius of ~25 miles, which is a conservative rule of thumb to get us started. Making radio contacts within this radius should be a slam dunk from this elevation, but it does depend on the actual terrain.

From the map, we can see that we should be able to work stations in Buena Vista and Salida, which are small mountain towns with a corresponding small ham radio population.  Some of these folks make it a habit to monitor 146.52 MHz to see what activity occurs on the calling frequency, which helps. But it helps to get the word out to the target audience that you will be on the air. The basic idea is to “send invitations” for your planned activation. The local radio club (Chaffee Lake Amateur Radio Association) has a groups.io list, so you could drop an email message there. If you know some of the hams in the area, you can always reach out and ask them to be listening for you. It is always good to post an ALERT and then a SPOT on SOTAwatch because some chasers may see that. Also, keep an eye on SOTAwatch for other SOTA activators that are on other summits.  During the summer months, it is common to encounter tourists, campers, hikers, or off-road enthusiasts on 2m simplex.

Looking at my Aspen Ridge logs, I see that I’ve worked K0MGL at his home station near Florrisant, at about 60 miles, with some mountains in the way. So the 25-mile radius shown on the map is quite conservative. (Much longer distances are possible.) Now, I probably would not be able to work K0MGL with just a handheld radio and a rubber duck antenna.

Which leads us to our third and final principle…

3. Every decibel of signal strength matters

VHF radio often gets described as being limited to “line of sight,” which is a helpful model but one that is incomplete. (See The Myth of VHF Line of Sight.) I often make VHF contacts beyond line of sight, bouncing signals around the mountains without knowing the actual radio path. These VHF SOTA contacts happen at the fringes of radio coverage. That is, there is just enough signal to complete a contact, but small changes in signal strength can make the difference between success and failure. So you should optimize your station as best you can.

First up is ditch the rubber duck antenna and get an antenna that is a half-wave in length on the 2-meter band. See A Better Antenna for Dualband Handhelds. Make sure it is a half-wave and not just one of those extended rubber duck antennas that are a quarter-wave. Those work a little better than the typical rubber duck, but the half-wave is far superior.

Another half-wave option is the roll-up J-pole antenna, such as the N9TAX Slim Jim antenna. (There is a slight difference in construction between a J-pole and a Slim Jim antenna but they are so similar, I consider them the same.) You can purchase this type of antenna already assembled, but it also makes for a fun project to build one from scratch. (Just search on the web for “2 meter j-pole antenna plan.”) You’ll need some way to support this antenna, such as a non-conductive pole or a rope strung from a tree.

The next step up in antenna performance is to add additional gain and directivity. I use the Arrow II 2m Yagi antenna, which provides about 6 dB of gain over a half-wave radiator. I normally just hold this antenna in my hand, but you can also set up a mast to support it.

Another option is to increase your power level. The typical HT puts out about 5 watts but a mobile radio can go up to 50 watts, a 10-dB improvement. While antenna improvements help on both transmit and receive, increased transmitter power only makes your transmitted signal stronger. However, if the other station is also running 50 watts in a vehicle or at home, more power from the summit tends to balance things out.

The key point here is that even a few decibels of improvement can yield more radio contacts.

Wrap It Up

So there we have it, three important principles to keep in mind when pursuing SOTA activations using VHF. I have had a ton of fun doing this, but I also know it can be frustrating. The most fun occurs when I make a long-distance contact that I did not expect. (My best DX from a SOTA summit using 2m FM is 245 miles.) Keeping these principles in mind helps to set expectations while providing some ideas for improving your odds of success.

73 Bob K0NR

The post The Truth About VHF SOTA appeared first on The KØNR Radio Site.

The Summits On The Air (SOTA) program offers a good set of tools for chasing and activating summits. Outside of the SOTA program, many different outdoor and hiking apps are also useful for planning and doing activations.

The tools I use have changed over time, so here’s an inventory of what I am currently using. This is not an exhaustive list, but my own personal, commonly-used list of tools. Recall that I typically chase and activate summits only on frequencies above 50 MHz, which affects how I use these apps.

Chasing

SOTAwatch is the main website for setting and monitoring Alerts and Spots, always useful.

The GoTo SOTA app on my iPhone is SOTA Goat, which can set and display alerts, spots, and other information. This app is very handy and useable.

I recently wrote about HamAlert, which I normally have set to let me know of any SOTA spot in the state of Colorado (W0C Association). I am looking for summits that I can work on VHF, so I monitor for only in-state activations.

Planning

For planning, the SOTA Atlas (Sotl.as) is an excellent mapping website. It offers some good filtering tools to view such things as unactivated summits, frequently-activated summits, summits that you have not activated this year, etc.

SOTA Atlas does more than just mapping. It includes pages that show other SOTA information.

Of course, the repository for all things SOTA is the SOTA Database. One handy feature for planning purposes is the Resources section associated with each summit. Here, your fellow SOTA enthusiasts may provide links or tips concerning activating a particular summit.

For more detailed mapping around a particular summit, I use GaiaGPS. I pay for the premium service that provides access to a wide variety of maps, which can be essential for finding the best access and approach to a summit. I use their iOS app, which I load with waypoints for summits in areas that I expect to activate.

Lately, I’ve been using AllTrails to gather route information for a particular hike or summit. There are many hiking apps out there, and you probably have your favorite.

Alerting & Spotting

To set an Alert or Spot, I use either SOTAwatch or SOTA Goat, already mentioned above. An Alert provides advance notice of an activation, while a Spot indicates that an activator is on the summit and on the air.

I have also found it helpful to maintain an email list of potential VHF chasers in my area, and I will drop them a quick email indicating that I’ll be on a summit at a particular time and frequency.  These folks may or may not pay attention to SOTAwatch, so pinging them via email lets them know a local activation is coming.

One app and website that I only use occasionally is SOTAmat (“SOTA Mate”). This is a very clever app that supports SOTA (and POTA) spotting when normal internet connectivity is not available. I have not used this app very often, but when I did, it was super helpful.

Logging

My hiking partner Joyce/K0JJW and I usually log on paper during an activation. When we get home, I transfer the paper log into an electronic format using the G0LGS SOTA Editor. This is the best, simple SOTA logging program I have found. Sorry, it only runs on Windows. It stores the log in CSV format, but it can also export the info into ADIF.

Sometimes I need to edit and manipulate the log file, especially when I do a combined SOTA + POTA activation. ADIF Master is an excellent tool for editing ADIF files. (Sorry, Windows only.)

Summary

This is an overview of the main tools I use for SOTA. It is quite awesome that we have these apps and websites available for free or at a very low cost.

What tools are you using for SOTA?

73 Bob K0NR

The post My Favorite SOTA Tools appeared first on The KØNR Radio Site.

Many of you already know about this wonderful alert tool: HamAlert. From the HamAlert website:

HamAlert is a system that allows you to get notifications when a desired station appears on the DX cluster, the Reverse Beacon Network, SOTAwatch, POTA, WWFF Spotline, or PSK Reporter. No need to keep checking these resources manually if you’re looking for a certain callsign, DXCC, CQ zone, IOTA island, SOTA summit or WWFF/POTA reference.

HamAlert is quite versatile, allowing you to tune its alerts to meet your needs. You do this by defining triggers that, well, trigger an alert. I won’t cover all of the possibilities here, but I will show you how I have my triggers set:

Most of these are just ham friends and family that I want to keep track of, see when they are on the air: K0JJW, KF9EY, KB9DPF, & W0BV. W0BV is a special case because he is an active DXer not too far from me, so it is helpful to see what he’s doing on 6 meters and HF. W0CLA and KV0CO are the callsigns of clubs I belong to. For these callsigns, the trigger is set for any activity on any band.

K0GU is a noted 6m enthusiast in Colorado that I follow because if something is happening on 6m, he is usually in the mix. (A major part of the challenge of 6 meters is knowing when the band opens.)

Probably the most important trigger for me is the Summit Association W0C, which alerts me whenever a SOTA activation is spotted in Colorado (W0C). I am only interested in working Activators on VHF/UHF, but I set the trigger for any band. Many times, activators are spotted only on HF, but they may still operate VHF/UHF. Similar to this is the POTA trigger for parks in Colorado. I just want to be alerted to park activations happening only in my state.

I have my callsign K0NR on the list because it is helpful to know where I am getting spotted. This can be very helpful when trying to work DX or activating a SOTA summit. If I am looking for a particular DX callsign, entity (country) or zone, I can add that to this list as well. When we travel, I may adjust these for local activity, depending on the situation.

I generally set up the triggers via the web interface and then receive the Alerts on my iPhone, via the HamAlert app, as shown below.

Anyway, take a look at this handy app and let me know how you use it.

73 Bob K0NR

The post HamAlert Is My Friend appeared first on The KØNR Radio Site.

I’ve been whining about the fact that for many years the 2m FM calling frequency, 146.52 MHz, was prohibited for use in VHF contests and Field Day. See The One Frequency You Should Never Use on Field Day. Well, the ARRL removed this restriction in 2015, so that issue has been resolved.

The CQ WW VHF contest also prohibited the use of 146.52 MHz, and up until now stuck with it. During the reconfiguration of this contest into two separate contests:  analog contest (CW/SSB/FM) and digital contest (FT8, FT4, etc.), the 146.52 rule was dropped. The rules now say:

Use of commonly recognized repeater frequencies is prohibited. Recognized FM simplex frequencies such as 146.49, .52, .55, and .58, and local-option simplex channels may be used for contest purposes.

Of course, this change is only relevant to the analog contest, as FM is not allowed in the digital contest.

This is a relatively minor change, not earth-shattering at all, but it cleans up an outdated rule in the CW WW VHF contest. This eliminates the need for me to explain to new VHF contesters that you can’t use the calling frequency.

73 Bob K0NR

The post CQ WW VHF Contest Allows 146.52 MHz appeared first on The KØNR Radio Site.

At first, I was just looking around on the web for some simple Rules of Thumb that compare the weak-signal performance of commonly used analog and digital modulation types. I was mostly focused on FT8 and FT4 but I also wanted to compare SSB and CW. I failed to find a simple comparison of these modes but I did find a number of good articles that compared some but not all of them. This article is my attempt to aggregate the available information into something easy to understand.

Disclaimers

I decided to leverage the work of others and to not try deriving everything from basic principles. I am telling myself that I am perfectly capable of doing the analysis but that I would never find the time to actually complete it. (Yeah, that’s my story, and I’m sticking to it.) Where the articles disagree, I tried to identify which one(s) had the most convincing analysis or rationale and used those values.

My goal is to compare common modulation types primarily in terms of weak-signal performance. This means focusing on how well a signal can be detected with low signal-to-noise ratio (SNR). I have ignored other factors, such as signal fading, frequency drift, multipath distortion, etc. Also ignored are factors such as the information rate provided by the modulation type and the required signal bandwidth. This is focused on having the ability to pass just enough info to make the contact.

Literature Survey

Searching the internet provided me with a number of good articles that have examined this topic, listed below in the References section. My approach is to compare the results of these articles and aggregate them into a concise summary. These minimum SNR values are listed in the table shown below, along with my aggregated conclusions in the righthand column.

Most of these articles presented SNR data in terms of a 2500 Hz bandwidth, with the goal of providing an easy comparison between modulation types. SSB is the widest signal discussed, and it roughly fits into a 2500 Hz bandwidth, which is often the IF bandwidth of the receiver being used. Some authors make this explicit by tagging this SNR as SNR2500.  It is common practice in communications work to normalize the bandwidth to 1 Hz, which indicates the modulation’s bandwidth efficiency. However, we’ll stick with SNR2500.

I started with the article by PA3FWM [Ref 1], which provides a look at many of the modes I was interested in comparing. Unfortunately, this article does not include FT4 and FT8. N6MW [Ref 2] has a good treatment of FT4 and FT8 as well as minimum SNR values for SSB and CW. These lined up well with the PA3FWM values, so that was a good sign. N6MW referenced the foundational article about FT4 and FT8, published in QEX, written by the FT4 and FT8 developers [Ref 3]. The KB9II article [Ref 4] focuses on VHF weak-signal performance and provides minimum SNRs for SSB, RTTY, CW, and PSK31. He introduces the concepts of SNR (average) and SNR (peak). I used the SNR (average) numbers in the table. The KF6HI [Ref 5] article provided another set of SNR values that lined up pretty well. Finally, I came across a presentation by K0LB and KK4SNO [Ref 6] that includes a slide summarizing SNR performance. Because it is slideware, it does not include much about the sources of their numbers, but it seems useful to include them in the table.

The authors have somewhat different approaches to determining their SNR2500 numbers, mostly related to the assumptions used. You may want to read through these papers to gain a better understanding of the fine points. Overall, there is good alignment on results, with a few exceptions.

SSB

The single-sideband SNR2500 values are a mix of 10 dB and 6 dB. Frankly, I think 10 dB is a bit high for “minimum SNR” because I’ve spent quite a bit of time making weak-signal VHF/UHF contacts with the signal right at the noise level. I’ve squeezed out radio contacts with SNR much less than 10 dB. I looked at the rationale supplied in the articles for this value and it is mostly just assumed. So I went with my own experience and chose something smaller, 6 dB, aligning with KB9II and KF6HI. Even this number might be a bit conservative.

RTTY

I found only four values for RTTY, and they vary quite a bit. After studying the articles, I judged KB9II to have the best justification, so I went with -9 dB. I suspect that the actual decode performance may vary depending on the type and quality of the detector.

CW

The SNR2500 numbers for CW varied significantly, over a range of 10 dB. One way to estimate CW performance is to use the bandwidth of the receiver and compare it to 2500 Hz. Using a typical CW filter bandwidth of 200 Hz, SNR2500 = 10 log (200/2500) = -11.0 dB. However, it is well-known that the human ear/brain combination provides additional signal processing. The classic article by W2RS [Ref 7] covers this topic quite well. Using actual on-the-air tests, the article explains that the skill of the operator can introduce a variation of 3 to 6 dB. Another interesting note is that if the operator knows in advance the type of information they are expecting (such as the callsign of the other station), it provides a 3-dB advantage.

We can and probably will debate the SNR2500 value for CW until the cows come home, but I decided to adopt -12 dB in the right-hand column. This is probably conservative for a highly skilled operator.

FT8, FT4

For FT8 and FT4, I used the N6MW values, which come directly from the FT4 and FT8 paper [Ref 3]. I rounded off to the nearest decibel to be consistent with the rest of the column.

JT65

The JT65 values are quite consistent. An article by K1JT [Ref 8] says JT65 SNR is “roughly -28 to -24 dB in 2500 Hz,” so I put -24 dB in the righthand column.

WSPR

WSPR is a popular beacon mode and the king of weak-signal reception. Signal reports are collected worldwide and shared via WSPRnet.org. WSPR performance will vary depending on the specific settings used on the software and we have some variation in the table. The K1JT & W1BW article [Ref 9] says, “The WSPR protocol is effective at signal-to-noise ratios as low as –28 dB in a 2500 Hz bandwidth, some 10 to 15 dB below the threshold of audibility.” So I used -28 dB in the aggregated column.

Conclusions

The rightmost column in the table provides a reasonable comparison of the listed modulation types. I don’t claim that the values are perfect, but they should be helpful in understanding the performance of these modes. These data show that SSB is the least sensitive mode, followed by RTTY and PSK31. As mentioned earlier, the CW number is open to debate but it performs better than RTTY and PSK31. This brings us to FT4 and FT8, which are commonly used WSJT protocols with reasonable throughput. (FT4 and FT8 using 7.5 and 15-second transmit/receive intervals.) JT65 operates at lower SNR, but it is really in a different category, It is designed for Earth-Moon-Earth contacts, using one-minute intervals. WSPR is also unique as a beaconing system and not designed for two-way radio contacts, but it does have the best SNR performance on the list.

When using this data, keep in mind that most of these modes degrade slowly so there may not be a sharp cutoff at an exact signal level. The values are Rules of Thumb, accurate to within a few dB.

Thanks to Jim/K5ND and Bob/WØBV for reviewing this article and providing feedback.

73 Bob K0NR

References

1. Signal/noise ratio of digital amateur modes – Pieter-Tjerk de Boer, PA3FWM

2. FT8 Modulation and Decoding – A Dive into SNR interpretation N6MW

3. The FT4 and FT8 Communication Protocols – Steve Franke, K9AN- Bill Somerville, G4WJS – Joe Taylor, K1JT

4. A Comparison of Common Digital Modes for Weak Signal VHF Communications – John Matz, KB9II

5. Signal to Noise Ratio, definition and application to Radio Communications – KF6HI

6. Digital Modes in Amateur Radio – Larry, K0LB and Scott, KK4SNO

7. The Weak-Signal Capability of the Human Ear – Ray Soifer, W2RS

8. EME with JT65 – Joe Taylor, K1JT

9. WSPRing Around the World – Joe Taylor, K1JT, and Bruce Walker, W1BW

The post Weak-Signal Performance of Common Modulation Formats appeared first on The KØNR Radio Site.

Six Meter WAS

Chasing States By Band

WAS Score Card