Have you noticed a lot more POTA and SOTA ops ending their exchange with “72”–?
I have! And I think it’s brilliant.
When I started performing field activations in CW a few years ago, I gravitated from using 73 to 72 at the end of my exchange. I saw it as a simple and clear way to let the other op know I was running QRP.
I got so many questions about my use of 72, though (as in a few emails or comments per week) I finally wrote this blog post so I could link to it in my replies.
These days, I hear 72 being used routinely and I love it!
72 is like a simple calling card to tell the other op know you’re running QRP power.
It’s all the better when both sides sign with 72–then it feels more like a QRP handshake!
Many thanks to HUAQIANG Gu (BD4LB) who shares the following information about his homemade L-Match. Note that BD4LB doesn’t speak English, and I don’t speak Chinese, so the following was machine-translated via Google Translate:
Homemade L-Match for Field Operating
by HUAQIANG Gu (BD4LB)
L-MATCH has a simple structure and is easy to make.
It is mainly composed of a coil and an adjustable capacitor.
The coil is made of copper wire with a diameter of 1.8mm, and the outer diameter of the coil is 50mm.
The capacitance of the thin film adjustable capacitor is 0pF–200pF.
When using, a balanced ground wire needs to be installed.
(Different bands, multiple quarter-wave length wires, and together. I use a row of wires. For example: two balanced ground wires 10 meters and 5 meters long, respectively 40 meters band and 20 meters band balanced ground wire.)
After many outdoor communications, I adjusted the end-fed antenna. The length of the radiator was 10 meters, which was appropriate.
One end of it is hung from the top of a 6-meter-long fiberglass fishing rod. On the other end, connect the red binding post of L-match.
Balance the ground wire and connect it to the black binding post. Spread it out on the ground.
The L-match is placed on the ground and connected to the HS1B or KVE60C antenna analyzer using a one meter long 50-3 coaxial cable. (This reduces the length and weight of the coaxial cable.)
When using an inverted V antenna, the length of the coaxial cable needs to be at least 8 meters.
My outdoor communication is mainly on the top of a hill in the park, or on the beach by the sea.
On the beach, there is plenty of space. In addition to setting up end-fed antennas, you can also set up inverted V antennas.
On the top of the mountain in the park, the space is limited, and it is difficult to deploy the 20-meter-long antenna oscillator. Only 10-meter end-fed antennas can be used.
After fixing the fishing rod, installing the antenna radiator and balanced ground wire, first connect the antenna analyzer KVE60C.
Use copper alligator clips to clip on the coil and adjust the adjustable capacitance to minimize the standing wave ratio of 7.023 MHz.
(Change different coil taps, adjust the adjustable capacitor, and try several times.)
I carry a compass to adjust the transmitting direction of the end-fed antenna. I won’t get lost.
The actual communication effect is quite good.
In the 40-meter band, it is suitable for short-distance communication within 800 kilometers.
In the 20-meter band, it is suitable for communication within 1000-2000 kilometers.
Many thanks to Dave (K1SWL) who shares the following field report:
October 6th POTA activation
by Dave (K1SWL)
I’m pretty much a died-in-the-wool CW guy. I’m not averse to dabbling in other modes, though. Friday, October 6, 2023, was such an occasion. I’d noted that there’d been little recent Digital activity in one of our area’s Parks. As if it needs more familiarity, it looms over I-91 only three miles from the Connecticut river. As a result, it’s been activated more than 75 times.
This was Mount Ascutney State Park in VT, and at 3144′, features a paved road to the summit. Off I went!
Finding a parking space at the summit lot wasn’t an issue. The top of the mountain was socked in above 2500 feet. Visibility was 30 to 50 feet, and sightseers were inexplicably scarce.
I normally use a 20M end-fed antenna and homebrew pneumatic launcher. The stunted trees at that elevation made that less practical. I used instead Hustler resonators for 10M and 20M atop the truck cab on a mag mount. I usually consider that setup a compromise, but at 2000 feet above average terrain (HAAT), it didn’t matter.
The operating position inside the truck is quite comfortable. A melamine-clad slab serves as the operating surface. (see above) The chain at the far end was a design ‘iteration’. I’d originally just supported that end on the passenger-side arm rest. I’d operated from the driver’s side, and one day got out, went around and absent-mindedly opened the passenger door. The whole station headed for the ground. I caught the rig but the Vibroplex Iambic paddles were a loss. A fabulous excuse for a Begali- and a hard protective case! When I’m operating from the truck, an IC-706MKIIg and 15-AH Bioenno battery does the honors. If gear needs to be carried any distance, the KX3 makes more sense. The station itself takes two minutes at most to set up.
So how’d it work out? A closeup of the WSJT-X screen (seee above) illustrates it. (The device is an MS Surface.) I was getting as many as 3 replies to my CQs at a time. I wound up ‘interleaving’ three contacts at a time. It got confusing! I need to look into ‘Fox/Hounds’ operation to speed things up for the future.
All in all- a great success. A total of 62 FT8 contacts in a little over 2 hours. 16 of these were on 10M at the start and the balance on 20M. The attached QSO Map (att. 4) shows the contact distribution- mainly eastern US with a few Europeans for good measure. Will I do it again? You bet!
Many thanks to Jim (KI7URL) who shares the following article about his portable field radio kit which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post. Jim writes:
(tr)USDx Ultralight Portable Kit
by Jim (KI7URL)
I like to take amateur radio with me wherever I go. In my backpack, I keep a Yaesu FT-60 (powered by 18650 batteries, but that is a different discussion). But I do not like to limit myself to VHF/UHF.
My wife, on the other hand, does not think my “go bag” should take up a significant portion of our suitcase when we travel. I did build a slimmed-down go kit with my Yaesu 891, but that was still north of 12 pounds (vetoed by Wife). Then, I made a go kit with my Yaesu 818, but that was still near the 10-pound zone (again, vetoed). I needed a slimmer package.
I turned to the likes of the QCX mini or other CW-only radios. The problem is that I still am far from proficient with my code, so relying only on CW was a bit more frustrating than I wanted it to be. The (tr)USDx, an open-source radio about the size of two stacked decks of cards, interested me in both price point and functionality. It has SSB, CW, and digital capabilities….on five different bands! Once it was in my hands, I had to build a kit around this new radio!
I want to keep my radio protected, so I started with a small dry box. On the inside, I printed a ‘redneck laminated’ (see also: packing taped) a quick setup guide for using the radio on digital modes if I ever have an in-field case of “the dumb.”
The radio is powered by a small RC battery. I chose this for size, weight, and availability (had it lying around from another project). When fully charged, it reads 12.6 volts. I added powerpole connectors to it because who does love powerpoles (be careful not to short the battery when adding power poles)? I have a small power adapter that goes from powerpoles to the 1.3mm connector so I can use my bench supply or other power sources without making another cable.
I have two antennas that I use (a K6ARK end fed and a QRP Guys No-Tune end fed with 26 gauge wire for 20m). But I like the QRP Guys one because I mostly do 20m and I think it was slightly lighter than the K6ARK antenna (don’t quote me on that though, I loaned the K6ARK one out and have not gotten it back). Plus, not having a tuner lightens my load as well!
Deployed for digital modes.
I have a retired smartphone in my kit that I use for some logging and some other ham-related apps, but mostly for FT8 using the FT8CN app. I also have WoAD on there and soon I hope I can get WinLink functionality with a small TNC as per this video by OH8STN. HF WinLink would be a good benefit with a lighter load than packing in a laptop or Raspberry Pi.
The kit weighs in at 2 pounds 6 ounces (just over a kilogram). This could be stripped down if I only did an SSB, Digital, or, gasp, a CW activation. But as it stands, the small form factor and low weight make the wife happy!
I was speaking with my buddy Joshua (N5FY) in mid September. He’d recently acquired an Elecraft KX1 and the topic came up about pairing the KX1 with the AX1 antenna. I realized that in all of my experimenting with the AX1, I’d never paired those two. What!?!
Time to fix that!
On Thursday, September 28, 2023, I had a nice midday window to play radio. After dropping my daughters off at their classes, I stopped by the French Broad Food Co-op and grabbed a container of their chicken noodle soup from the refrigerator section.
I then made my way up the Blue Ridge Parkway (K-3378) to the Craggy Gardens Picnic Area at Bearpin Gap–one of my favorite spots on the BRP.
Despite stunning weather and the beginnings of fall foliage, the parking lot was pretty empty. After all, it was a Thursday and a good week or two before leaf-lookers descend upon western North Carolina.
I pretty much had the picnic area to myself (there was one other person there). I picked a picnic table at the top of the hill under the trees.
Mahlzeit!
When my wife and I lived and worked in Munich, the salutation I learned before any other was “Mahlzeit!” At Siemens, I remember walking through the hallways and people I’d never met before exclaimed “Mahlzeit!” as I passed by.
I quickly learned that Mahlzeit essentially meant “Lunch Time!” and I still say it today to my family when I’m about to make or grab some lunch. Funny how these things stick with you.
Now where was I–? Oh yes…
First thing I did at Craggy was set up my stove to start heating the soup. I show this in my activation video below.
If interested, here are the components of my stove kit:
Next, it dawned on me that I would need to attach the AX1 counterpoise to the KX1. I didn’t bring one of my copper clamps to attach to the outside of the AX1’s BNC connector, so I needed to find another grounding point on the KX1.
I then remembered that the KX1 has two thumb screws on the bottom of the radio. Knowing Elecraft, I assumed that these screws could be used as an attachment point for a counterpoise, but I wanted to confirm that the screw itself had a direct connection to ground.
Fortunately, I keep a small multimeter in my supplemental gear bag in my car. It’s an inexpensive Allosun Pocket Multimeter. I use it for things like this: testing.
I set the multimeter to read continuity and then placed one probe on the outside of the KX1’s female BNC and the other on one of the thumb screws. Sure enough, there was a direct connection to ground. I didn’t need to worry about the KX1 chassis paint insulating the connection to ground because the thumb screw had a direct connection. Perfect! Continue reading Amazing POTA Fun: Pairing the Elecraft KX1 and AX1…but first, a little lunch!→
I have a favor to ask. You might remember our friend Wlod (US7IGN) has not only written a book about living in Kiev during the Russian invasion of Ukraine, but was also the subject of an amazing, award-winning audio documentary by Cicely Fell.
Both Wlod and Cicely are dear friends and it’s been my honor to have played a small part in the making of this documentary and, more importantly, introducing these two amazing people to each other.
“Call Signs” has been nominated for another award and the public–no matter where you live in the world–is allowed to vote. Voting requires no login and is very easy to do. The login form is in French, but Cicely explains how to vote below.
It would be meaningful to me if you took a moment to register your vote today.
Thank you & 72! –Thomas (K4SWL)
Cicely writes:
Dear Thomas,
I’m so happy that ‘Call Signs’ – the documentary that you were so instrumental in making happen! – is nominated for this year’s Phonurgia Nova Awards (International Contest of Radiophonic Creation, taking place in Paris in early November). You can read more about the contest here.
It’s so wonderful that Wlod’s story has captured people’s imagination and is being recognised in this way. In addition to the prizes awarded by the jury, there is an audience award, where the public gets to vote for their favourite piece.
Many thanks to Phil (KF6IF) who shares the following article about his portable field radio kit which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post. Phil writes:
Hi Thomas,
As requested here is my Elecraft KX2 Field Kit:
Antenna Gear:
AX-1 homebrew clone
AXB1 Whip BiPod
90 degree BNC connector
PL259 / BNC connector
13′ ground wire with lug
K6ARK Winder with two 25′ speaker wires, banana plugs, and plastic carabiners
Many thanks to Dennis (WQ7O) who shares the following article about his portable field radio kit which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post. Check out Dennis’ field kit below:
Thomas,
Like you, I have a number of QRP radios with differing deployments. Some go in the trunk of the car, others go in my shirt pocket.
Here is a fully featured QCX-Mini station in a Tupperware container.
While I believe QRP operation and non resonant antennas should be mutually exclusive, I have the Elecraft T1 as an option. Also when I burn a hole in the sky going QRO, the TalentCell gives me full 5 watts. If needed they both fit in the antenna sack. The 9 volt rechargeable is for normal use.
Lately, I’ve been kitting out another fully self-contained field radio kit that would be small enough to fit in my EDC (everyday carry) laptop bag–something super compact.
I’ve been getting some great ideas from those of you who have added your kits to the Field Radio Kit Gallery.
[By the way, if you’ve submitted your kit to the gallery and haven’t seen it yet, note that I’m posting these in the order received and there are many in the pipeline!]
I’ll likely build my EDC field kit around the Elecraft KX1 or the Mountain Topper MTR-3B, then pair it with a good wire antenna.
My EDC laptop bag: the Tom Bihn Stowaway
But this process got me thinking: if money was no object, and I wanted the most compact and versatile multi-band field kit, what radio and antenna system would I choose?
My answer? A kit built around the Elecraft KX2 and AX1 antenna.
In my experience, the KX2 AX1 combo is hard to beat. It’s compact, effective, low-profile, and you can set it up pretty much anywhere.
Let’s explore my reasoning here keeping in mind–in my world–this is a very deep rabbit hole to go down. I’ll do my best–no promises–to keep this as concise as possible:
Compact, Low-Profile, Self-Supporting, and Simple
Here are all of the components of my typical KX2 AX1 field kit:
This is all that is needed for a field activation.
And if you’re an SSB operator? You don’t really need a microphone because one is built into the KX2 (that said, I’d suggest you build a compact mic if you plan to do a lot of SSB operating).
If I wanted to make this kit even a bit more versatile? I’d add a kneeboard to the list. This gives one the ability to operate without a picnic table.
What makes this field kit so portable is that the KX2 is one of the most compact general coverage HF transceivers on the market.
It’s certainly the most compact (at time of posting) when you realize that two important components–the battery and ATU–are internal options.
The AX1 antenna is also incredibly compact–it comes apart in such a way that no one component is longer than about 6 inches. What you see in the photo above is the entire radio and antenna system.
Yes: A Compromise
Sure–and let’s get this out of the way right up-front–the AX1 is a compromised antenna, and being a massive fan of simple wire antennas myself, I know a properly deployed wire in a tree is going to provide better gain each and every time.
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Have you noticed a lot more POTA and SOTA ops ending their exchange with “72”–?
