Amateur Radio Weekly – Issue 410

Amateur Radio Weekly

Inovato and N0LSR Design support and promote the OHB project
OHB public server keeps your HamClock running indefinitely.
N0LSR Design

Useful knots and applications for Radio Amateurs (PDF)
253 pages discussing ropes, knots, and their application within the Radio Amateur community.
PA3DJS

Fifty things you can do with a software defined radio
This project attempts to create GNU Radio flowgraphs for each of those items.
Onno VK6FLAB

Ham Radio Manifesto: From utility to creativity
The current approach to Amateur Radio, focused on communication and disaster relief, is no longer sufficient to attract today’s technical profiles.
F4JXQ

TPRFN launches live network views
Your real-time pulse on system performance.
TPRFN

KX2 battery capacity when charged from different voltage sources
I was curious to see how a lower charging voltage would correspond to capacity.
AE5X

Online museum tours and talks
You don’t need to travel the world to visit and enjoy many of the most impressive museums related to Ham Radio and radio communications.
Amateur Radio Events

Ham Radio Dashboard
Displays solar weather, band conditions, the 11 closest Ham Radio satellites, and data from PSK Reporter.
Andreas Peters

United States Bunkers on the Air
USBOTA joined the Worldwide Bunkers on the Air (WWBOTA).
USBOTA

The Last of the hybrids: Kenwood TS-830s
These transceivers aren’t “all-tube” in the boatanchor sense, nor are they fully solid-state like modern SDRs
Ham Radio QRP

Video

AMSAT discusses futureGEO
President Glasbrenner talks feasibility of a geostationary Ham sat.
AMSAT

The story of the Hams that founded Zenith
What happened to the factory that put a television in every American living room?
The Last Shift

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Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.

Second Edition of VHF, Summits, and More

Big news — I’m proud to announce that the Second Edition of my book VHF, Summits, and More is now available. I’ve received tons of positive feedback on the first edition, published in 2019, and I decided it was time for an update. This new version is printed in color, which greatly enhances the photos and graphics.

This book is an easy-to-understand introduction to VHF/UHF ham radio with an emphasis on mountaintop VHF operation. I’ve enjoyed ham radio and writing about it ever since I received my first FCC license. Although I’ve used the ham bands from 160m to 10cm (10 GHz), I find the VHF and higher frequencies the most interesting. This is mainly because of the interplay between mountains, Height Above Average Terrain (HAAT), and VHF propagation. VHF has lots of spectrum, lots of modes, and lots of fun challenges.

For the second edition, I gave everything a fresh look. I updated every chapter and added 100 pages of new material. In Part I, the VHF tutorial section, I added new chapters to improve the treatment of basic VHF/UHF: Popular VHF/UHF Bands, Antennas, Coaxial Cables & Connectors, and WSJT-X Digital Modes. Part II covers topics that originated from my blog, often based on questions I hear from newer hams.  In Part III, which is focused on SOTA, I added several chapters on how to be successful doing VHF SOTA, and I added a few new trip reports. I also added some information on combined SOTA/POTA activations.

The book is available in two formats: a color print edition and a Kindle edition, both available from Amazon. The print version ships immediately; the Kindle version will follow shortly.

Order your copy now. Operators are standing by.
(Actually, just use the Amazon site.)

73 Bob K0NR

The post Second Edition of VHF, Summits, and More 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].

Recent 630m Fun!


Working new stations on 630m at this time of the solar cycle can be a rare occasion but two 'new ones' recently found their way into my logbook!

The first was Frank, K6FOD, in South Pasadena, to the north-east of Los Angeles. Now if Frank can have success on 630m in this densely populated location, then most amateurs should be able to have fun on the 630m band!




Frank is running about 200W output into a short inverted-L. Up until recently, his antenna was a large wire loop pointing east-west with which he had a lot of success working stations towards the east. He and I had several skeds while he was using the loop but since I was directly in the null of the loop, I was never able to detect a trace of his signal, nor was he able to hear me! The break through came when the vertical was erected ... but I'll let Frank tell more of the story ...

As a long-time shortwave listener I had always been very curious about the realm below the AM broadcast band, so not too long after I got my ham license in 2018 I started working on a 630m rig.

Most ops on that band use inverted-L antennas, but they are highly dependent on a robust system of ground radials. At my location, there just isn’t enough open ground to lay out an extensive radial network. This seemed like a show-stopper.

However, John Langridge KB5NJD, who was writing the MF/LF column for CQ magazine, suggested that I try a vertical loop tuned by a vacuum variable capacitor, which does not use a ground connection at the feed point. He mentioned that this was being used at the time by Ben Gelb N1VF. Between Ben and John, they helped out greatly on getting it going. Mine ended up with a circumference of about 100 feet.

By adding a 630m class D amp to my K3S, which has an internal 630m transverter, I was able to get on the air with digital modes, which at the time were JT9 for two-way QSOs and WSPR for beacon modes. The winter of 2019-2020, I worked a dozen ops in six states, the most distant being South Dakota. My WSPR signal was heard from Hawaii to the Cayman Islands.

Due to their size compared with the wavelength of the 630m band, loop antennas like the one I built are notoriously inefficient. Based on measuring RF amperage to the antenna, I calculated that it was sending only 47 milliwatts into the atmosphere. On the other hand, the winter of 2019-2020 was near a solar minimum, the point in the 11-year solar cycle when conditions are best for the low bands. And there was also a lot of activity on 630m that year because it was a fairly newly approved band and was attracting a lot of experimenters.

One downside of the vertical loops is that they are fairly directional, with a deep null off their sides. Because mine pointed east-west, it was exceptionally difficult to hear or be heard by stations due north.

After that experience, other parts of life got in the way, and I didn’t get back onto the 630m band until the winter of 2024-25. That winter, I used the same rig and vertical loop antenna as before, and worked eight ops in six states and Mexico.

But due north was still unreachable. Steve VE7SL and I gave it a good try, but neither of us could hear the other. So in the fall of 2025, despite my limited ability to lay out ground radials, I thought I’d give an inverted-L antenna a try. John KB5NJD again provided great guidance, and Steve VE7SL also lent very useful ideas.

At my location, going super tall wasn’t going to be feasible, so I ended up with a lightweight aluminum mast of 36 feet height. Because of my lot’s dimensions, instead of having one top wire to form the inverted L, I used two top wires in opposite directions, each 50 feet long — making what some call a “Tee Antenna.” 

Like inverted-L’s, its small size compared to the 630m wavelength meant it would require a substantial loading coil. I made this using a popular approach of a large coil wrapped around a 5-gallon plastic bucket, with a small coil inside it on a turnable rod, which allowed the total inductance to be adjusted. The big coil also had tap points. An impedance matching transformer was wrapped on a stack of four FT240-77 toroids. For a rig I decided to try an SDR transceiver which opened up possibilities of CW and SSB voice in addition to digital modes.

For the ground system, I tried laying out a set of 18 radial wires ranging in length from about 10 to 80 feet due to the site’s available space. My antenna analyzer indicated that R_feed was around 62 ohms. Measurement with an RF ammeter showed that about 1.25 watt was now getting into the atmosphere (this being the effective isotropic radiated power, or EIRP). The FCC limits 630m ham transmission to 5 watts EIRP, which means I have ample room for improvement, hopefully by adding however many more ground radial wires I can squeeze into my limited space.

After six weeks of operating in January-February 2026, this season I’ve worked six ops so far in three states and British Columbia. Hoping to add more if I can improve the antenna’s ground network.

When not in use for 630m, I’ve also attached the Tee Antenna to a multicoupler serving a small “skimmer farm” of SDRs that monitor FT8, CW and WSPR signals on ham bands from 630 to 10 meters. In addition, I’ve used it with an SDR for receive-only DX listening for non-directional beacons (NDBs), airport beacons that transmit below the AM broadcast band in North America. So far the Tee Antenna seems more sensitive than a number of other antenna designs I’ve tried for NDB listening. I also plan to use a remote tuner placed at the antenna to allow it to be used for CW, FT8 and voice QSOs on the HF bands.

K6FOD - 36' 'T' for 630m


Loading coil / variometer


Antenna impedance matching transformer

The other new contact was with fellow-Canadian, Karl, VE6KDX, in eastern central Alberta.




The antenna is a 160m Inv-L to which I switch in the Loading coil and matching transformer. It's all build to the N1FD Diagrams. https://www.n1fd.org/2019/10/27/630m-match/ I'm running 8 raised radials approximately 20m long 24" above ground on wooded survey stakes.


The LPF is a 5th Order Butterworth design good for 800W using 3 big Amidon T-225-2 cores and 4 Capacitors, It's housed in an old Palomar 1-30mHz filter case.

Icom IC-705 TX/RX on 80m 3.674.20mHz into the XVTR


The MiniKits XVTR is from AUS which I had to build and enjoyed doing so. https://www.minikits.com.au/eme223

I drive the tranverter with 1W from the IC-705 and the XVTR Drives the Amp with 1-2W. The 630m Amp is powered with 24v for 220W output into the home built LPF. (36v gets 510w Output)


The Amp is from Greece and came assembled on it's PCB but I had to add the heatsink, The only thing you have to watch out for is the heatsink is at full input positive voltage so make putting it into an enclosure a little challenging. https://www.dxworld-e.com/product-page/am-cw-digi-linear-amplifier-800w-mf-hf-0-4-3mhz

The Auto Sensing Antenna RX-TX Switch is also from Greece and DX World. https://www.dxworld-e.com/product-page/auto-rx-tx-switch-1-80mhz-1200w

Karl has put together a great looking station and should provide a lot of excitement for the guys back east when they hear a VE6 on 630!

Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

ARRL DX CW contest

 

I spent a lot of time in the contest chair this weekend. While the Olympics were on and on Sunday, the much-anticipated U.S. vs. Canada hockey matchup sparked sports fever in our house, but it belongs to my wife, not me. For me, it was all about contesting, so I happily settled behind the radio.
I began early Saturday morning and continued until Sunday evening, wrapping up at 23:45. Conditions fluctuated significantly: on Sunday morning, I noticed a lot of what I call “wobbling” in station signals. Solar activity picked up on Sunday, and I found many stations calling me were just above the noise floor. I ran for about 90% of the contest and enjoyed every minute. I can always tell when I’m spotted suddenly as the floodgates open with callers!

 
By the end of each evening, fatigue started to set in, and I found myself mixing up S and H or 7 and 8. When that happens, I know it’s time to pull the plug and walk away before frustration takes over.
The station, PC, and antenna all operated flawlessly. I had contacts from South America, Hawaii, and even Africa. There were also quite a few QRP stations reporting just 5 watts I double-checked, thinking they meant 500, but nope, it was 5! One of my many pins now claims South Korea, though I know that’s not accurate. When I looked up the call, I realized my mistake, but by then, the station had already moved on.
All in all, it was a memorable weekend of contesting, full of challenges and highlights.

 


Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

ARRL DX CW contest

 

I spent a lot of time in the contest chair this weekend. While the Olympics were on and on Sunday, the much-anticipated U.S. vs. Canada hockey matchup sparked sports fever in our house, but it belongs to my wife, not me. For me, it was all about contesting, so I happily settled behind the radio.
I began early Saturday morning and continued until Sunday evening, wrapping up at 23:45. Conditions fluctuated significantly: on Sunday morning, I noticed a lot of what I call “wobbling” in station signals. Solar activity picked up on Sunday, and I found many stations calling me were just above the noise floor. I ran for about 90% of the contest and enjoyed every minute. I can always tell when I’m spotted suddenly as the floodgates open with callers!

 
By the end of each evening, fatigue started to set in, and I found myself mixing up S and H or 7 and 8. When that happens, I know it’s time to pull the plug and walk away before frustration takes over.
The station, PC, and antenna all operated flawlessly. I had contacts from South America, Hawaii, and even Africa. There were also quite a few QRP stations reporting just 5 watts I double-checked, thinking they meant 500, but nope, it was 5! One of my many pins now claims South Korea, though I know that’s not accurate. When I looked up the call, I realized my mistake, but by then, the station had already moved on.
All in all, it was a memorable weekend of contesting, full of challenges and highlights.

 


Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

ARRL DX CW contest

 

I spent a lot of time in the contest chair this weekend. While the Olympics were on and on Sunday, the much-anticipated U.S. vs. Canada hockey matchup sparked sports fever in our house, but it belongs to my wife, not me. For me, it was all about contesting, so I happily settled behind the radio.
I began early Saturday morning and continued until Sunday evening, wrapping up at 23:45. Conditions fluctuated significantly: on Sunday morning, I noticed a lot of what I call “wobbling” in station signals. Solar activity picked up on Sunday, and I found many stations calling me were just above the noise floor. I ran for about 90% of the contest and enjoyed every minute. I can always tell when I’m spotted suddenly as the floodgates open with callers!

 
By the end of each evening, fatigue started to set in, and I found myself mixing up S and H or 7 and 8. When that happens, I know it’s time to pull the plug and walk away before frustration takes over.
The station, PC, and antenna all operated flawlessly. I had contacts from South America, Hawaii, and even Africa. There were also quite a few QRP stations reporting just 5 watts I double-checked, thinking they meant 500, but nope, it was 5! One of my many pins now claims South Korea, though I know that’s not accurate. When I looked up the call, I realized my mistake, but by then, the station had already moved on.
All in all, it was a memorable weekend of contesting, full of challenges and highlights.

 


Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

ICQPodcast Episode 477 – ARRL Bylaw 46 Changes

In this episode, we join Martin Butler M1MRB, Dan Romanchik KB6NU, Caryn Eve Murray KD2GUT, Edmund Spicer M0MNG, and Ed Durrant DD5LP to discuss the latest Amateur / Ham Radio news. Colin Butler (M6BOY) rounds up the news in brief, and the episode's feature is ARRL Bylaw 46 Changes.

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


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

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