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The Ham Nation folks invited me on to talk about the Colorado 14er Event last night. Thanks for the invite! This turned out to be a concise look at the 14er event with lots of great photos of past operations.

Here’s the video (my segment was 20 minutes long):

We have lots of information on the event at ham14er.org.

73 Bob K0NR

The post Colorado 14er Event on Ham Nation appeared first on The KØNR Radio Site.

Amateur Radio Fun in the Colorado Mountains
August 4 through 7, 2023
www.ham14er.orgAmateur Radio operators from around Colorado will be climbing Colorado Summits On The Air (SOTA) peaks and communicating with other radio amateurs across the state and around the world. Join in on the fun during the annual event by activating a summit or contacting (chasing) the mountaintop stations.This event is normally held the first full weekend in August. Again this year, we will add two bonus days to the Colorado 14er Event. The main two days remain Saturday and Sunday (Aug 5 & 6), while the bonus days are Friday Aug 4 and Monday Aug 7th, for those SOTA enthusiasts that need more than two days of SOTA fun! Be aware that many mountaintop activators will hit the trail early with the goal of being off the summits by (1800 UTC) noon due to lightning safety concerns.

The 14er event includes Summits On the Air (SOTA) peaks, which provide over 1700 summits to activate. (See the W0C SOTA web page or browse the SOTA Atlas.) The Colorado 14er Event was started in 1991, about 19 years before the SOTA program was set up in Colorado. As SOTA grew in popularity, this event expanded from just the 14,000-foot mountains (14ers) to include all of the SOTA summits in the state. We still call it the Colorado 14er Event because, well, that’s where it all started and the 14ers are the iconic summits in the state.

Important: The recommended 2m FM frequencies have been changed to 146.58, 146.55, and 146.49 MHz, to align with the use of the North America Adventure Frequency for SOTA (146.58). The National Simplex Calling Frequency (146.52) may be used as appropriate. There will be plenty of action on the other ham bands, for more information see the operating frequencies page.

Resources:
Colorado 14er Event webpage  – Everything to Know About The Colorado 14er Event
Beginner Guide – For the first-time activator
Ham14er Groups.io  – Discussion Group for the event
Colorado SOTA groups.io – Colorado SOTA discussion group

Colorado 14er Event Task Force
[email protected]

The post 2023 Colorado 14er Event (Summits On The Air) appeared first on The KØNR Radio Site.

I caused a minor kerfuffle on Twitter recently, when I posted this:

This connector, properly called a PL-259, is the most common RF connector for ham radio use. The female counterpart is called the SO-239 connector. While these connectors are often “UHF” connectors, they actually don’t perform very well at those frequencies (300 to 3000 MHz). So I feel justified in disparaging that name.

The tweet generated a large number of replies, mostly in support of my anti-UHF-naming sentiment. It seems that other highly-educated and thoughtful radio amateurs agree with me. (It seems that the wise hams out there always agree with me.) You should be able to view the thread here: https://twitter.com/K0NR/status/1653575723838492672

Some people pushed back on the anti-UHF sentiment, usually saying that it is the common name for this connecter. A few folks pointed out that Amphenol calls these things “UHF Connectors”, which did surprise me. Who am I to disagree with this manufacturer of high-quality connectors? Of course, Amphenol also says this:

Originally intended for use as a video connector in radar applications, UHF coaxial connectors are general purpose units developed for use in low frequency systems from 0.6 – 300 MHz. Invented for use in the radio industry in the 1930’s, UHF is an acronym for Ultra High Frequency because at the time 300 MHz was considered high frequency. They can be used when impedance mating is not required.

Well, there you have it: the connector was named UHF back when UHF meant up to 300 MHz. (Today, UHF means 300 to 3000 MHz). I particularly like the comment “They can be used when impedance mating is not required.” What? That does not sound good for RF applications. I do agree that these connectors can generally be used to 300 MHz, but these days the ITU calls that VHF (30 to 300 MHz).

Wikipedia provides a more complete explanation, worth reading.

OK, so the name “UHF” is archaic but it has kind of stuck, the way old terminology sometimes does. I am still going to avoid using this term because it really should be deprecated.

And don’t use these connectors above 300 MHz (UHF frequencies). Unless you have to. Which I did last weekend when the only cable available for my 440 MHz antenna had a PL-259 connector on it.

73 Bob K0NR

The post About That UHF Connector appeared first on The KØNR Radio Site.

My article that describes last year’s SOTA/POTA/VHF contest activation from Pikes Peak appears in the June issue of QST magazine. This VHF/UHF activation occurred on the Saturday of the ARRL June VHF Contest and qualified for Summits On The Air (W0C/FR-004 Pikes Peak) and Parks On The Air (K-4404 Pike National Forest). The article highlights the use of the North America Adventure Frequency of 146.58 MHz.

I made 80 radio contacts that day, on the 6m, 2m, 1.25m, 70cm, and 23cm bands. Not a great score for the VHF contest but quite nice for a VHF SOTA and POTA activation. My primary piece of equipment was the ICOM IC-705, which enabled all modes on the main VHF/UHF frequencies.

If you are an ARRL member, look for the article on Page 58 of the print edition of June QST or the online version. Not an ARRL member? Darn, you should fix that if you want to read articles published in QST.

If you are an ARRL member, please look at the article and consider voting for it in the QST Cover Plaque Award. Thanks!

73 Bob K0NR

The post June QST: SOTA, POTA and VHF Contest appeared first on The KØNR Radio Site.

We were looking for a SOTA summit to activate near Salida, so I started to poke around using SOTLAS. There is still plenty of snow at the higher elevations, so we wanted to stay lower. SOTLAS has some useful filtering features that allow you to show only the summits of interest. Initially, I looked for a summit that Joyce/K0JJW and I had not yet activated.

Then I noticed that an unnamed summit (W0C/SC-102) had never been activated, not by anyone. When a summit has never been activated, it is often because it is really difficult to access or it is on private land. Using Gaiagps, my preferred mapping software, I checked out land ownership and the surrounding terrain.

The summit is on land managed by the Bureau of Land Management (BLM). The box labeled Sand Gulch is Colorado State land. This area is clearly on public land without any private property to deal with. We considered two routes to get to the summit. One option is to hike up from the west, which would probably work. But we noticed a 4WD road that approached from the north side that might provide better access. We weren’t sure how difficult the road would be to drive but we decided to give it a try. The road turned out to be easy 4WD, with just a few steep sections that might prove troublesome if the road were muddy. It presented no problem for our stock Jeep Wrangler. There were several side roads not shown on the map that could be a diversion, so having Gaiagps on my iPhone was helpful.

The parking spot for the Jeep is shown on the map above. We were careful with the route finding for this summit, even though it is only a mile or so. We wanted to stay on top of the ridgeline and not get lost in one of the side drainages. Gaiagps on my phone recorded the hike as 1.1 miles one way with an elevation gain of 360 feet, so not very difficult.

The photo below shows the typical terrain as we hiked along the ridge. There was plenty of pinion pine and juniper, along with a surprising number of small cacti. Since the summit is unnamed, we decided to call it Cactus Ridge.

We made contacts mostly on 2m FM (146.52 MHz) using the 50-watt Yaesu FT-90 transceiver driving a 3-element Yagi antenna. I was curious to see how far we could work because the summit is not that high and sits roughly in the canyon of the Arkansas River, between Salida and Canon City. As expected, Salida stations (KD0VHD, K0LPR) were close by and easy to work. Stations in Buena Vista (KF0IHL, KD0MRC, W0BV) also came in quite strong. Our best DX for the day might be N0KM near Center, CO at a distance of 55 miles. But we also worked K0EEP, N0CFM, and KA0SDE camping somewhere near Jefferson, perhaps 60 miles or so, not sure exactly. Although they were due north of us, we had to point the Yagi antenna to the south to work them, apparently getting a nice reflection off one of the high peaks. Similarly, when we worked K0LTH in Guffey (to the north), we had to point the antenna south. We tried to work Amanda/K1DDN in Canon City but were unsuccessful. I thought we might be able to funnel a signal down the canyon to her with a few favorable reflections. No luck with that, but you never know until you try.

Thanks to everyone that listened for us and worked us!

The weather report was sketchy for the day but conditions were cloudy and warm (50 deg F) when we were on the summit at 11:30 AM. Later in the day, after we were back in Salida, we had rain and snow coming down. Springtime in the Rockies.

This was a very enjoyable summit, partially because it had the experience of exploring something new. The easy 4WD road was a pleasant surprise and made us wonder where the other roads in the area lead. At 8280 feet, this summit is only worth two SOTA points. But it’s not about the points, right?

73 Bob K0NR

The post Exploring a New SOTA Summit (W0C/SC-102) appeared first on The KØNR Radio Site.

I do a lot of SOTA activating using 2m FM and have developed a few operating habits that can really make a difference. These may seem obvious but might be overlooked by operators new to the game. To get an overview of using VHF for SOTA, look at this article: How to Do A VHF SOTA Activation.

Here are three operating tips when using 2m FM for SOTA:

1. Upgrade Your Antenna

A handheld radio is commonly used for SOTA operation because it is a self-contained, compact radio. These radios always come with a rubber duck (electrically-short monopole) antenna. These antennas vary in quality but they are universally poor performers compared to a half-wave radiator. I’ve measured the effectiveness of many rubber duck antennas on 2 meters and they are somewhere between 8 and 12 dB worse than a half-wave radiator. So an easy upgrade is to use a half-wave telescoping antenna. Another popular option with a half-wave radiator is the roll-up J-pole (often called a “Slim Jim” antenna). An even better choice is a small 3-element Yagi such as the 146-3 from Arrow antenna,  which is about 6 dB better than a halfwave antenna. Keep in mind that the Yagi should be held vertically-oriented for FM operating.

2. Open Your Squelch

The squelch circuit in an FM receiver requires the signal to be large enough to flip the squelch open. When operating at weak signal levels, the squelch may mask a signal that is actually readable. A recommended technique is to just open up the squelch control and let the FM noise come through. This maximizes the opportunity to pick out that weak signal out of the noise.

3. Point Your Antenna Everywhere

If you have a directional antenna, make sure you methodically point it in a variety of directions when calling CQ. For example, with a 3-element Yagi, you should divide up the 360 degrees around you into 45-degree sections. Point north, make a call, point northeast, make a call, point east, make a call, and so forth. Also be aware that the direct path to another station may not be the strongest path. This is especially true if you have tall summits around you that can block or reflect your signal. Many times I’ve pointed in the “right direction” to work another station but then found that the signals were strongest with the antenna pointed away from the direct path. So the secret is go ahead and try different antenna orientations to maximize the signal strength, even when you know the physical direction to the other station. Sometimes the radio waves decide to take another path.

Those are my three tips for today.
Do you have any to add?

73 Bob K0NR

The post Three Tips for 2m FM SOTA appeared first on The KØNR Radio Site.

While doing a presentation about choosing the right coaxial cable, someone suggested that RG-8X (also called “Mini 8”) might be the best general-purpose cable for amateur radio. There is a lot to like about RG-8X. It is about 1/4-inch in diameter, and is flexible and affordable. This comment made me realize that I default to a larger cable (LMR-400 or RG-8) for everyday use and consider RG-8X as the cable for lightweight, portable applications (such as SOTA and POTA). But perhaps I am underestimating the capabilities of RG-8X.

So let’s take a look at the specs on RG-8X, using the DXEngineering RG-8X datasheet. Other manufacturers of RG-8X will have similar specs.

Power Rating

Most general-purpose amateur radio operation occurs at power levels of up to 100 watts for frequencies of 3 MHz to 54 MHz and up to 50 watts from 144 MHz to 450 MHz. I am thinking in terms of a station that has a 100-watt radio for HF and 6m and a typical 50-watt FM dual-band radio for 2m and 70 cm.

These power levels are easily handled by RG-8X. In fact, the cable is spec’d for over 1 kW for all of the HF bands. At 50 MHz, the power rating drops to 900 watts and further reduces to 400 watts at 150 MHz. DX Engineering does not specify the power at 440 MHz, so I looked at other websites and found that the power rating drops off to about 100 watts. So power handling is not going to be an issue.

Signal Loss

Signal loss may be a more significant limitation. How much loss are we going to be comfortable with? That is difficult to answer because each of us may make different tradeoffs to accomplish our radio operating objectives. As an upper bound, I hate to see the cable loss go as high as 3 dB, which corresponds to losing half the power in the cable! But living with 1 dB might be acceptable, which is 20% power loss. So let’s use that.

(Someone reading this is thinking: 3 dB is only half an S-unit, it won’t matter that much. To which I say: it won’t matter unless you are operating near the noise floor and 3 dB is enough loss to have your signal disappear.)

The table above shows the loss in dB per 100 feet. At 100 feet, the loss creeps up to 1.5 dB at 30 MHz. Let’s stretch our 1 dB rule of thumb to 1.5 dB, which means the loss is reasonable for all the HF bands using a 100-foot cable. At 50 MHz, the loss increases to 2.3 dB/100 feet, so to stay within 1 dB or so, we would need to limit our cable length to 50 feet. At 150 MHz, the loss rises to 3.8 dB/100 feet so we should keep our cable length less than about 25 feet. We don’t have a spec for the loss at 450 MHz but checking other websites reveals a typical loss of 6.6 dB/100 feet at 400 MHz. A 25-foot cable at 450 MHz will have a little over 1.6 dB loss.

So now the problem becomes clear: signal loss at high frequencies will be the limiting factor. (This is why I tend to grab a larger cable because I’m often operating above 50 MHz.)

Conclusions

So what can we conclude in very broad terms? Is RG-8X a good choice for a “general purpose” coaxial cable? I am going to say “Yes, But”. The key issue is signal loss and that is driven by the frequency being used and the length of the cable. So Yes, RG-8X is a good general-purpose coaxial cable but watch out for signal loss and cable length at high frequencies.

Here’s my Rules of Thumb for this cable:

For HF, RG-8X is great for all bands with cable lengths of 100 feet (maybe longer).
For 6m, RG-8X is good with a cable length of up to 50 feet.
For 2m and 70 cm, RG-8X is good with a cable length of up to 25 feet.

In all cases, checking the manufacturer’s specs and doing your own calculations is recommended. For a slightly deeper look at coaxial cables, see Hey, Which Coaxial Cable Should I Use? 

73 Bob K0NR

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