Archive for the ‘ham radio’ Category
Height Above Average Terrain
November 25th, 2025 | 
Author: When I get asked why I only use VHF/UHF frequencies for my Summits On The Air (SOTA) activations, I usually reply with:
Height Above Average Terrain
More specifically, I mean that using VHF for SOTA is fun because Height Above Average Terrain (HAAT) has a dramatic effect on the propagation of my radio signal.
HAAT has a specific definition, found in the FCC regulations. HAAT basically describes the height of a transmitter relative to the surrounding terrain in all directions at distances of 3 to 16 km. This HAAT calculator tool provides the HAAT of a site based on its latitude and longitude. Note that the FCC definition of HAAT compares against the terrain relatively close to the transmitter, 16 km (10 miles). For SOTA purposes, we are more concerned with distances further away.
In a recent presentation on mountaintop VHF operating (Hamcon Colorado), I provided these two contrasting examples to drive home the importance of HAAT.
Punkin Center
Punkin Center is a small town located on the eastern plains of Colorado. The elevation is 5364 feet, and its HAAT is roughly zero feet. That is, the terrain is flat. Punkin Center is a fine place to be, but it is not a very good VHF location. The radio range using a 5-watt VHF handheld radio is about 4 miles.
Pikes Peak
Compare this to America’s Mountain, Pikes Peak, which has an elevation of 14,115 feet and a HAAT of 4,445 feet. That is, it rises more than 4,000 feet above the surrounding terrain. (The height advantage is even more pronounced when looking further east towards Kansas, where the highest elevation is ~4,000 feet.) Based on my experience operating from there, the VHF handheld range is over 100 miles.
The improved HAAT of Pikes Peak provides a VHF radio range that is 25 times better than Punkin Center. Again, nothing wrong with Punkin Center, but if I want to make VHF contacts, I’ll choose Pikes Peak.
Let’s compare this to using the High Frequency (HF) bands. The normal propagation mode on HF is skywave propagation via the F layer, which supports radio propagation across North America and around the world (depending on frequency, time of day, solar conditions, blah blah blah). The radio signal refracts off the ionosphere and can go very long distances. From Pikes Peak, I can work the world. From Punkin Center, I can work the world. Not much difference, except the views from Pikes are generally better, and the oxygen is less plentiful.
So when I hike up a mountain, I am excited to get out the VHF gear and see what contacts I can make due to the improved HAAT. I don’t get as excited about working HF, because I can do that from home…or Punkin Center, or other places, with similar results.
Other SOTA activators see it differently, and that is just fine. (VHF contacts represent only ~20% of all SOTA contacts.) There are many ways to enjoy SOTA and ham radio. Just make sure you have fun messing around with radios.
73 Bob K0NR
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Confirming K0NR Does Have HF Equipment
A few days ago, someone told me that a rumor is circulating that I don’t own any gear capable of operating on the high-frequency (HF) bands. I laughed out loud, wondering where this came from.
Actually, I know where this comes from: most of my postings here at k0nr.com are oriented towards VHF operating, often from the top of a summit. I fully admit that VHF/UHF has always been my favorite part of the amateur radio spectrum.
And I do operate on the HF bands.
Home Station
The photo above shows my ham shack set up at home. The primary transceiver is an ICOM IC-7610, which covers the HF bands and 6 meters. To the left is an ICOM IC-9700 that I use for 2m, 70cm, and 23cm. An ACOM 1000 linear amplifier sits at the far left. It is usually configured for 6m, just waiting for the band to open.
Here is a closer look at the two transceivers. Hey, look at that, the IC-7610 is listening to 20m CW. Yes, I even operate CW.
My antenna farm includes two towers but they are used for VHF/UHF antennas. For the HF bands, I use wire antennas. This article describes the end-fed wire antenna I have been using for the past 5 years. It covers 40m through 6m with one antenna.
Operating Results
I run hot and cold on chasing DX, but over time, I have made many DX contacts and worked quite a few countries. I favor the DX potential of the higher bands: 20m, 17m, 15m, 12m, and 10m. Recently, I discovered that the 30m band can be a lot of fun, too. My current stats are: 205 DXCC Entities and 39 (out of 40) CQ Zones. Still looking to work Zone 34, Northeastern Africa. I’ve also been working on Worked All States (WAS) for each band, having completed 40m, 30m, 20m, 17m, and 6m.
Going Portable with HF
Joyce/K0JJW and I often operate portable on the HF bands, almost always a Parks On The Air (POTA) activation. Our favorite radio for POTA is a Yaesu FT-991, which covers the HF bands along with VHF/UHF. Almost all of the POTA work is on HF but sometimes we do make a few VHF contacts.
We also have an ICOM IC-705, also covering all bands, and is especially useful for backpack portability. We favor VHF/UHF for SOTA but sometimes we will use the IC-705 to make some HF SOTA contacts. We have a variety of wire antennas, all different types of end-fed designs. The IC-705 does not have a built-in antenna tuner, so we take along a small manual tuner.
Wrap Up
So there you have it, I do have some HF gear and I do use it!
Remember, the universal purpose of amateur radio is to have fun messing around with radios. Using whatever amateur band you choose.
73 Bob K0NR
The post Confirming K0NR Does Have HF Equipment appeared first on The KØNR Radio Site.
Pile-Up Control System
PUCS: Take control of the pile-up!
Every special event station (SES) operator knows the thrill — and the chaos — of a true pile-up. The excitement of dozens of stations calling you simultaneously can quickly turn into frustration when QRM, doubles, and missed calls clutter the frequency. Wouldn’t it be great if there were a way to bring order to that chaos without losing the fun of real-time operating?
Enter PUCS, the Pile-Up Control System, a fully open-source, web-based platform designed by and for radio amateurs. Born from the ingenuity of the Radio Scouting Fellowship PA3EFR/J, PUCS elegantly blends traditional ham ingenuity with modern AI-assisted software development. The result is a modular, flexible system that any club or individual can tailor to their own operating style — from large-scale SES activities to small club field days.
PUCS can be seen operational at pucs.pa3efr.nl
From Normandy to the Netherlands
The idea for PUCS was sparked during an SES operation on the beaches of Normandy, where operators of TM80DDAY overheard multiple Australian colleagues discussing a private sign-up system for QSOs. Intrigued but unable to obtain the software, Erwin PA3EFR and his team decided to build their own version — and then share it freely with the world. With the help of AI tools and some Python wizard Barry, PC1K, PUCS was born. It was much later when Erwin decided to develop PUCS within his own environment.
Today, PUCS is freely available, fully documented, and open to anyone willing to experiment. It’s more than just software — it’s an invitation to collaborate, learn, and contribute to a smarter way of managing pile-ups.
What Makes PUCS Unique
At its heart, PUCS is a distributed system consisting of two parts:
- Frontend (commercial hosting): This is the public entry point where operators register their callsigns to join the queue. Think of it as a digital “waiting room” — transparent, fair, and visible to everyone.
- Backend (local PC): Here’s where the magic happens. The backend checks QRZ.com logbooks every minute, automatically removes callsigns that have already been worked, and provides an admin dashboard to manage the queue, export logs, and adjust settings on the fly.
Open Source, Open Spirit
PUCS is more than a tool — it’s a philosophy. The creators explicitly invite others to modify, enhance, and restyle the system to their own preferences. Whether you want to change the interface colors, add logging features, integrate digital modes, or redesign the operator dashboard, the code is yours to explore. There’s no hidden agenda, no locked components — just open code and open collaboration.
All scripts, examples, and documentation are available on GitHub:
https://github.com/PA3EFR/PUCS
Why You Should Try It
PUCS is a perfect project for your club’s next technical workshop. It offers practical lessons in networking, APIs, databases, and web hosting — all wrapped around a real amateur radio application.
Beyond that, it promotes fairness in pile-ups, gives weaker stations a chance to make contact, and even allows SWLs to log their participation.
So fire up your soldering iron if you must, but this time, your “kit” is made of code.
Download PUCS, make it your own, and bring calm to your next pile-up.
As Erwin, PA3EFR, says: “Ask AI as your friend for support — and enjoy your own moments of challenge!” On behalf of the Radio Scouting Fellowship PA3EFR/J we look forward to see you on our PUCS screens at a next special event occasion.
~ Sander PD9HIX
Three Useful HT Accessories
Here are three affordable accessories that can help round out your VHF/UHF handheld transceiver (HT) kit. These items can significantly improve the performance of your radio and make it more useful.
1. A Halfwave Antenna for 2m
I’ve already written about the RH660 antenna, which is a huge improvement over a typical rubber duck antenna. Make sure you get the version with the proper connector for your HT.
2. A Compact Magmount Antenna
Another handy antenna is a small magnetic-mount antenna for the 2m and 70cm bands. The primary usage of this antenna is on the roof of a vehicle, connected to your HT inside your vehicle. This puts the antenna on the roof, outside of the vehicle, working in concert with the effective ground plane of the metal roof. Note that for the magnet to hold, the roof needs to be made of a ferrous metal, not aluminum, fiberglass, fabric, etc.
This antenna can also function as a portable/temporary antenna by placing it on a steel object such as the top of a refrigerator, a cookie sheet, metal door frame, filing cabinet, metal folding chair, etc. The antenna is about 19 inches in length, so it packs well for travel. There are many models available, including this one on Amazon.
3. A Few RF Adapters
It seems that we often encounter incompatible RF connectors, so it is good to have a few adapters available to make the connection.
SMA Male/Female Adapters
These days, handheld transceivers have SMA antenna connectors, but some models provide a male connector, while other radios have a female connector. Having a few SMA adapters can deal with this issue.
SMA to BNC Adapters
BNC connectors often show on on various radios and cables, so it can be handy to adapt this popular connector to an SMA.
SMA to PL-259 Adapters
The PL-259 and its companion SO-239 are the most popular RF connectors for ham radio use, so you may encounter one of these. (I try not to call them UHF connectors: see About That UHF Connector.) They are not used on HTs, but you may find an antenna cable with one of these attached. Again, an adapter or two can help you make the connection to an SMA connector.
These are some handy devices to have along with your HT.
Any other suggestions?
73 Bob K0NR
P.S. If you are having trouble identifying the connector on your HT, take a look at this article: What’s That Connector On My HT?
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It’s our 50th Anniversary!
Commemorative VHF Net check-in
Tuesday 7 October at 8 pm (PST)
SARC will be hosting its usual net at 8 pm (Pacific time) on Tuesday, October 7 on frequency 147.360 MHz +600 KHz, tone 110.9 Hz for a special commemoration of the society’s founding on Tuesday, October 7, 1975.
Members and non-members are invited to check in. We'll also be connecting to IRLP reflector 9005 for any stations who wish to join from outside our repeater’s footprint. You can connect a repeater or your personal device by dialing node 9005.
You can read about SARC's history at The Communicator Digital Edition: The Communicator July - August 2025
We encourage SARC members, past students, non-members, and readers of The Communicator to check in on this historic net and we hope to commemorate our 50th anniversary with a record number of check ins.
~
A New 2m/70cm Telescoping Antenna
I came across this new antenna, the TWAYRDIO RH 660S, mentioned in this Ham Radio Crash Course video. I have previously been recommending the TWAYRDIO TH770 antenna via this post. The RH 660S is a newer dual-band 2m/70cm telescoping antenna from the same company.
For Summits On The Air (SOTA), I generally take along such an antenna. The performance of any half-wave antenna on a handheld radio is always much better than the standard rubber duck. Although a 3-element Yagi antenna provides even better performance, it has to be pointed in the right direction. Sometimes, we will set up the RH 660 or TH 770 on a small vertical pole (actually a camera monopod with a homebrew BNC attachment). This allows us to monitor and work the band with an omnidirectional antenna without having to hold or point the Yagi. Much more convenient while sitting there eating lunch.
A key advantage to an omnidirectional antenna is that it is always pointed in the right direction.
The RH660 is available with the three standard connectors: BNC, SMA Male and SMA female. Make sure you pick the right one that matches your radio.
On our most recent SOTA activation, I did a quick comparison between the old TH 770 and the new RH 660 on 2 meters. The RH 660 seemed to perform ever so slightly better, but that was probably within the measurement error of the test. It certainly was not worse than the TH 770. I only did the comparison test on 2 meters, as that is the GO TO band for VHF SOTA. However, the antenna seemed to work OK on 70cm as well.
The packaging on the antenna indicates 3.0 dBi gain on 144 MHz and 5.0 dBi gain on 430 MHz. Do I believe those numbers? Not really, but they are probably close. (An ideal halfwave radiator has a gain of 2.2 dBi.) Note that the newer antenna does not have the magic tuning lump in the middle of the radiating element, which simplifies the mechanical design. This is the main advantage of the new antenna: no lump in the middle, resulting in a slimmer and sturdier design.
Summary
I am pleased with this new design, and I now recommend it as a good compact antenna for portable use. As with all telescoping 2m half-wave antennas, it is long and should be handled with care. Otherwise, you can poke someone’s eye out, break it in two, or snap the connector off your HT.
The RH660 antenna is available at Amazon for ~$17. At this price, why wouldn’t you have one in your backpack or Go Bag?
73 Bob K0NR
The post A New 2m/70cm Telescoping Antenna appeared first on The KØNR Radio Site.
ARRL – Pass The Bill
You’ve probably seen the messages about the ARRL push for relief from antenna restrictions by Home Owners Associations (HOAs). If not, take a look here. It is clear that excessively tight HOA restrictions are a significant barrier to getting started in ham radio.
ARRL has launched a nationwide grassroots campaign aimed at securing the passage of federal legislation that would grant Amateur Radio Operators the same rights to install antennas on their property as those enjoyed by users of TV antennas, wireless internet, and flagpoles.
The campaign, announced in an ARRL Member Bulletin on September 17, 2025, follows the reintroduction of the Amateur Radio Emergency Preparedness Act in February 2025 (see ARRL News 02/07/2025). The bipartisan bills — H.R.1094 in the House and S.459 in the Senate — are designed to prevent restrictive homeowners’ association (HOA) rules that currently prohibit or severely limit the installation of amateur radio antennas, even when such antennas are hidden in trees, placed in attics, mounted on vehicles, or look like flagpoles.
While the ARRL is pushing for this bill, I have not seen much written about what is actually IN the bill. You can read the entire text here: HR 1094 – Amateur Radio Emergency Preparedness Act.
But here’s my summary. The bill requires that specific amateur radio antennas not require approval from HOAs or similar organizations:
- Antennas that are 1 meter or less in diameter
- Flagpole antennas, not to exceed 43 feet in height
- Wire antennas – minimally obtrusive wire antennas
- Vertical antennas – not to exceed 43 feet in height
Note that this does not mean you will have the right to put up a 60-foot tower with multiple large antennas on it. Some folks are probably disappointed in the limited nature of this bill. My view is that it is a reasonable accommodation to basic ham radio operation, very reasonable for urban and suburban environments. If you want to build the ultimate contest station, you’ll need to buy some rural property. This ARRL page provides some background on why this bill makes sense.
I am somewhat surprised by the 43-foot height limit for vertical antennas. This is apparently a carryover from previous ARRL legislative attempts. I would settle for something shorter than this…but what the heck. For reference, a quarter-wave vertical for the 40m band is about 33 feet high.
I think the ARRL has lined up the legislation, the lobbyists, and some Congresspeople to push this through. Can we get this passed? I don’t know, but I suggest we all get behind this by making our voices heard in Congress. The ARRL has made this VERY EASY to do. Just go here: https://send-a-letter.org/hoa/
That’s my view. What do you think?
73 Bob K0NR
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