Category Archives: Digital Modes

Digital Modes, Field Reports, FT4, FT8, Guest Posts, How To, News, Portable, POTA, QRP

Karl Heinz’s Pocket-Sized Digital HF Station

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Many thanks to Karl (K5KHK) for sharing this guest post, which originally appeared on his blog, Karl Heinz Kremer’s Ramblings:

A Digital Station in Your Pocket

by Karl Heinz (K5KHK)

How small can a complete station to work FT4/8 be? With the QRP-Labs QMX, we have a transceiver that certainly fits the bill for a small station. By itself it can only be used for CW, to use the digital modes, one has to combine it with a computer. Even the smallest laptop is too big the fit into the pockets of my cargo pants – we are trying a pocket sized station after all 😉

In this article, I will describe how to use a QMX transceiver and an iPhone to activate a POTA park with FT8.

The Components

My QMX is the original that was released at FDIM 2023, so it covers 80m to 20m. Mine is serial number #20.

My iPhone is small enough, but unlike Android based phones, the QMX cannot be connected directly to the phone. Apple sells a “camera adapter”, which plugs into the phones Lightning port on one side and provides a USB connection on the other end. $29 for the original Apple part was a bit hard to swallow, so I opted for something cheaper straight from China’s “we clone everything” factories: https://amzn.to/3WDSfUc

[Please note: All Amazon links are affiliate that support QRPer.com.]

 

The picture shows both a USB and a lightning port on the adapter. This should allow the phone to be powered/charged while the adapter is being used – more about that later.

Another limitation is the antenna: The QMX does not have a built-in antenna tuner, and even my QRP sized ZM-2 would have to live in a different pocket 🙂 My plan is to use a resonant antenna so that I would not need a tuner.

The easiest antenna with a good match is a dipole, but that is a bit more challenging to deploy in the field, so I opted for an end-fed halfway (or EFHW) antenna with a 49:1 transformer. I 3D printed a winder that allowed a BNC connector and the transformer to be mounted on the wire winder:

The design came from Thingiverse: https://www.thingiverse.com/thing:2871679

Because I am using a different toroid for the transformer, I had to remove the “bump” that is holding the toroid in place. Going forward, I may change the design a bit more to have so that I can fit more wire on the winder.

For those familiar with the transformers usually used for EFHW antennas, the picture shows two things that are different: As I’ve already mentioned, I am using a different toroid (the Fair-Rite 2661102002 core, which is a type 61), and a different winding pattern. More about that in a future post.

To power my station, I am using a TalentCell rechargeable 12V power bank:  https://amzn.to/3snTyr8

First Test

With everything in place, I tried to make a quick FT8 contact from home with this setup, but with my “big” EFHW antenna in my backyard. Because it was just a quick test, I did not even bother to hook up the charging cable for my phone (more on that later).

The software I am using is iFTx, which supports both FT4 and FT8.

I connected the phone to the adapter from above, connected the adapter via a USB cable to the QMX, and connected the QMX to a 12V power supply (unlike anywhere else in ham radio, 12V here means 12.0V and not the usual 13.8V), and hooked up the antenna to an antenna tuner and then to the EFHW in my back yard.

I answered an FT8 CQ call and successfully completed the FT8 exchange. The software does the automatic sequencing of the different messages, so it is very straight forward to use. With this first contact, I verified that the iPhone/adapter/QMX setup does work.

The Real Test

The next attempt was while camping at Hamlin Beach State Park (US-2068). I set up everything just like at home, but because I was planning on being on the air for a while. I also hooked up the cable to charge my phone while I was operating.

I was able to receive stations, but could not transmit. What made the troubleshooting more complex is that during setup, I created some sparks (that is why I do not like the barrel connector for power). I was pretty sure that the QMX was not involved, but not being able to transmit kind of suggested that I killed the finals. So I put everything away and used my KX2 instead.

Back home, I did some troubleshooting and hooked up a straight key to the QMX and it worked: I was able to finish a few CW QSOS without a problem, so the finals were definitely OK. I then set up the system again for FT8, and sure enough, I was able to make a contact. Because it was a quick test, I did not bother to use the power cable for the phone. By now, most of you probably know what the culprit was, but because I did not spell things out like this, I was still in the dark.

Success At Last

Fast forward a few more days… We went back to Hamlin Beach State Park – but this time to the picnic area – and I set up my station again. And sure enough, once everything was set up, the QMX did not transmit. This is when I took a step back and reviewed everything I had done so far, and slowly I came to the realization that when I provide power through the adapter to the phone, the QMX would not transmit.

I was able to finish my FT8 activation with my pocket sized digital station. I did run into one problem however: iFTx allows to automatically determine one’s grid square – which of course is important for FT8. When I enabled that, it correctly put me into FT13 at first, but a few QSOs later it switched me to JJ00aa – I reported this as a bug to the developer.

Using iFTx with the iPhone

The connection from the phone to the QMX is audio only. iOS does not allow an application to open a serial port connection (unlike Android). This means that the QMX will not receive any frequency information from the phone, and also no PTT signal. For this setup to work, the operator has to make sure that the QMX is tuned to the correct frequency that the correct band is selected in iFTx, and that the QMX is set to VOX mode (this is in the Digi Interface menu).

When configuring iFTx, it is possible to select a “Special Interest Activity” like POTA. This is then added to the CQ call as in “CQ POTA K5KHK FN13”.

As I’ve mentioned before, the application will automatically sequence the correct messages when a station answers the call.
Once the QSO is completed, it will be logged to the iFTx internal log, which can be exported via the usual “send to” methods available in iOS (e.g. email the log, save as a file, …).

When exporting the log, there is a choice of exporting everything, or only the new QSOs since the last export. This will create an ADIF file, which can be submitted to the POTA program, or imported into any other logging program.

At the end, I was successful in building a “pocket sized” digital station based on the QMX, I just need a fully charged phone and cannot depend on charging it while operating.

Click here to check out more articles from Karl on his blog!

Digital Modes, Field Reports, FT8, Guest Posts, POTA, Videos

KK4Z: Achieving Another Kilo Despite Solar Interference

2 Comments

Many thanks to Scott (KK4Z) who shares the following post from his blog KK4Z.com:

By the Hand of God at US-2173

by Scott (KK4Z)

I book my campsites often months in advance to ensure I get a good campsite. This particular trip was postponed twice due to typical life events that take precedence over having a little fun. Even this trip was not without its own issues. My wife and I forgot that this weekend was also Mother’s Day and unknown to us at the time of the booking was that there was going to be a 4 major Coronal Mass Ejections (CME) making an earth strike during the trip.

The last time I witnessed solar storms of this magnatude, I was in Gulfport MS doing EmComm for my Church in the aftermath of Hurricane Katrina. It was a humbling experience and it shaped my EmComm Philosophy.

I use the same gear for EmComm and FunComm. The equipment gets tested and exercised, and I remain proficient in its use. I also have an understanding of its strengths and weaknesses.

Most trips I take my go box.

It stays packed and contains everthing except a battery or generator to operate. I do keep a small switching power supply for mains power when it is available. Here is a look at the inside.

I have built rack mount or shelf type go boxes and in general, I do not like them. I have deployed to real disasters and found what I have here works the best for me. I do this enough that I am up and running in minutes. One thing I like is the versatility of being able to adapt my radio to the space I have to set up in. Your Milage May Vary, but for me and my 26 years in EmComm; this works best for me.

This weekend was spent at F.D. Roosevelt State Park (US-2173) near Warm Springs GA. The park was named after Franklin Delano Roosevelt. He suffered from Polio and often would travel to Warm Springs GA for hydrotherapy. He built a residence there often referred to as “The Little White Hose”. During his presidency, he established the Civilian Conservation Core (CCC) during the Great Depression. This provided jobs to young single men to help families who had difficulty finding jobs. The CCC built much of the park.

The park contains 9,049 acres (largest in GA) and is built along the Pine Mountain Ridge. It is the southern most moutain range east of the Mississippi River. The highest point is Dowdell’s Knob at 1,395 ft and is a popular POTA and SOTA (W4G/CE-004) site. I took the Radio Flyer and stayed at the campgrounds near Lake Delano.

I arrived there right at 1300 hrs eastern (check-in time) and quickly got myself settled and ready to go. I knew the solar storms were coming and that my time maybe short. I wanted to finish my kilo here (#6) and needed 310 QSO’s. I had already postponed this trip twice so I was a little edgy. My gear for the trip was my 28.5′ Random Wire Antenna with the Peter my IC-7300. I had my Lenovo Thinkpad T-14 laptop and used mains power. The nice part about the antenna besides it performance, is I get zero complaints from park employees. No wires in the trees nor holes in the ground.

Friday’s band conditions were okay. There was lots pof QSB and I stuck with FT8 (35 watts). CW in these more rural parks can be iffy and this go I needed quantity. I started at 1430 hrs eastern and by oooo hrs Saturday (Friday Night) I had 134 QSO’s and when I quit at 2315 hrs I had a total of 230.

Saturday morning, after a quick breakfast I started up again at 0730 hrs. I operated until 1140 hrs when the bottom dropped. Luckily, I ended up with 338 QSO’s including 3 that were mader after the CME hit.

I decided my time would be best spent at home to spend Mother’s Day with my Lovely Bride so I packed up and headed for the house. My stats refelected band conditions and even though I made quite a few contacts, I only had three DX entities: Alaska, Canada and Mexico. I made contacts in 40 of the 50 states.

Operating this weekend reminded me that as reliable as HF commnications can be, it does have its Achilles Heel. For those in EmComm, never stop practicing, refining your techniques, or keeping your gear in order. For everyone else, it’s just another day in paradise.

73 de Scott

Video:

Articles, Digital Modes, Guest Posts, How To, News, QRP

Getting Started with HF Digital Modes (Without Breaking the Bank)

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Many thanks to Joe (N0LSD) who shares the following guest post:

Getting Started with HF Digital Modes – Without Breaking the Bank

by Joe (N0LSD)

Amateur radio can be an expensive hobby:  the reasons are myriad, made more difficult for newcomers because they tend to not have the experience to know what their requirements might be.  Brick-and-mortar stores where one might bounce ideas off knowledgeable staff, browse the aisles, and walk away with a suitable set-up are pretty few and far between.  Similarly, asking on various internet forums will often be met with, “It depends…” –followed by a wall of text filled with jargon and terminology that can be…intimidating.

For newcomers that maybe don’t have the time to invest in learning CW right off the hop, and perhaps get a bit of mic fright, digital modes such as FT8, JS8, and the like tend to be a great fit.  While “shack-in-a-box” solutions by the big-name manufacturers offer convenience, this convenience comes at a price that can be cost-prohibitive.

What follows is a QRP digital modes kit that I’ve experimented with over the last year.  No single piece of this kit cost more than US$150, and the entire kit can be had for under US$600.  What’s more, nearly everything can be purchased from Amazon.

We’ll start with the most expensive part of this kit:  the radio, which is the Tr(u)SDX.  It can be had on Amazon for US$138, and covers 20m, 30m, 40m, 60m, and 80m bands.  It is a quirky little radio with a sub-par speaker and a tiny little microphone.

The Tr(u)SDX is just about as bare-bones as one can get with an HF transceiver, and is decidedly a compromise.  However, unlike other ultra-compact transceivers, this one will do CW, it will do voice, and it will do *any* digital mode.  It can run on USB power at 1 watt output (micro-USB port on the side of the case); but it can also run on 12v (nominal) power via a 5.5mm x 2.1mm barrel connector on the top of the unit.

I’m powering this radio with a US$43 battery bank (Romoss Sense8P+), and a USB-C to 5.5 x 2.1mm cable (US$8.99) –both available on Amazon.  This battery bank will keep the Tr(u)SDX going for hours –long enough to do multiple POTA activations.  And, because there’s no special adapters, the battery bank can be re-charged in the same manner as a cell phone –or even off a small solar panel.

The sound card interface is the Digirig (US$57) with a US$19.97 cable that is TRRS 3.5mm on one end, and breaks out separate Mic and Speaker 3.5mm TRS.  Now, I will say that a recent firmware revision on the Tr(u)SDX has been demonstrated by the developers of the radio to allow for audio through the micro-USB connector of the radio – so the use of a sound card interface *may* be redundant.  However, in viewing the demonstration video for this, it seems rather dependent upon finding the right micro-USB to USB-A cable; with no clear indication on where one can obtain a cable that meets the specification.  Now, add a USB-C to USB-A or a USB-C to USB-C cable to interface with the computing device, and we’re in business!

So far we have a radio, power, and a way to get sound in and out of the radio.  Now, let’s talk about antennas.  Of course, one can homebrew an antenna for the cost of parts and time in construction and testing.  For the kit I’m using, I went with the N9SAB OCF Dipole –specifically because I do a lot of 80m QRP work.  Also available from N9SAB is a 6m-80m random-wire end-fed for US$89.99 from his eBay store.

If using a non-resonant antenna, an antenna tuner will be needed:  I went with the ATX-100 (US$126 from Amazon).  The reason I went with this is because it recharges with USB-C, which is consistent with everything else in this kit.

For coax, I personally use Times Microwave LMR-240 –a 50-foot length terminated in BNC is US$65 on Amazon.  For something less bulky, perhaps RG-316 from ABR Industries (abrind.com) might fit the bill  The ABR-240 coax at 50-feet in length is US$58.  For a jumper from the tuner to the radio, I use a 3ft RG316 cable from Amazon – which cost me US$13.99.

All that’s left is a device to run software…this can be a Raspberry Pi, or one’s laptop, certainly –however, these are bulky and require special power…and are a pain to re-charge easily.  Another solution is something one might already have:  an Android smartphone.  There are apps (some free, some paid) for RTTY, PSK31/63, WSPR, SSTV – these have been out for some time.  Additionally, one can do many of the modes contained in FLDigi, using the AndFLMsg app (not available on the Play Store –one has to download the .apk file from a 3rd party).  However, what I’ve been using –especially on POTA activations – is FT8CN.  This allows for full-function FT8 using just an Android phone –which can also be charged via USB-C.

[Note: eBay, Amazon and ABR links below are affiliate/partner and support QRPer.com at no cost to you]

Tr(u)SDX $138.00 Amazon
N9SAB Random Wire End-Fed $89.95 N9SAB eBay Store
ATU-100 Antenna Tuner $126.00 Amazon
RG316 Coax Jumper (3ft) $13.99 Amazon
USB-C to 5.5×2.1mm cable $8.99 Amazon
ABR-240 50 ft Coax $58.00 abrind.com
Romoss Sense8P+ Battery Bank $42.99 Amazon
DigiRig MobileSoundcard Interface $49.97 digirig.net/store
uSDX Cable for DigiRig Mobile $19.97 digirig.net/store
Total $547.86

This kit is –for sure– a compromise:  one isn’t going to bust pile-ups or win contests with it  However, for a “starter kit” that can easily be carried in a small backpack that can not only be used for HF digital modes, but also can do SSB voice and CW, it will at least get an operator on the air and enjoying the bands –without breaking the bank.

Digital Modes, Morse Code, New Products, News, Portable, QRPer Notes

QRPer Notes: One CW Question, CW Haptic Device, and Easy Elecraft KX2 FT8 & FT4

4 Comments

Because I receive so many tips from readers here on QRPer, I wanted way to share them in a concise newsletter format.  To that end, welcome to another QRPer Notes, a collection of links to interesting stories and tips making waves in the world of radio!

VE6LK’s “One CW Question” YouTube Series

My good friend, Vince (VE6LK), came up with a great idea a few weeks ago: reach out to CW ops and ask one question that might help newcomers to Morse Code. Each video is 2-3 minutes long and features a number of ham radio operators who operate CW (I’m chuffed to be one of them).  I’ve learned something from each of these videos. Click here for the full playlist, or start watching via the embedded player below:

LICWC CW Haptic Device

Many thanks to Perry (N5PJ) who shares this video from Kyle (AA0Z):

Simple FT8/FT4 via a KX2 and iPhone

Many thanks to Jason (KD9ZHF) who shares the following video from Mark (KD7DTS):

Digital Modes, Field Reports, FT8, Guest Posts, News, Portable, POTA, QRP, Travel

For Conrad, DC Travel = DC POTA!

5 Comments

Washington, DC Field Report

By: Conrad Trautmann, N2YCH

January 30, 2024

Periodically, I travel to Washington, DC for my job. On my latest trip, I carved out some time to activate some parks. The hotel I was staying at is just a few minutes away from the National Mall, which provides many activation options on the POTA website. After scoping it out on Google Earth and researching trails using the National Parks mobile app and web sites, I settled on the Jefferson Memorial, K-0792 as my first stop which is a two-fer with the National Mall, K-0655.

Photo of Jefferson Memorial

Just steps away is the George Mason Memorial where the Potomac Heritage Trail National Scenic Trail, K-4564 passes right through and is located along the East bank of the Lower Potomac River. The Captain John Smith Chesapeake National Historic Trail, K-4567 runs by as well. The bench I found on the shore of the river met the minimum 100’ rule for both trails and was also located in the National Mall park, so this location was a three-fer.

Photo of George Mason Memorial
View of the Potomac River
Bench along walking path near George Mason Memorial

I tried to travel as light as possible this trip. The gear I chose to bring was the Elecraft KX2 along with the AX1 antenna and my laptop with the USB sound card and CIV cable.

Samsung laptop with Electraft KX2 and AX1 antenna

The January winter weather was mild, in the low 40’s F so setting up and activating outside wasn’t a problem. With it being off season for tourists, I had the park almost all to myself.  There were signs posted at the memorial asking visitors to be quiet and respectful, so the last thing I wanted to do was set up on the steps and draw attention to myself. I found a wall near the Tidal Basin’s water’s edge and was able to set up out of the way of anyone wanting to photograph the memorial, but still be on the property. Continue reading For Conrad, DC Travel = DC POTA! →

Digital Modes, Field Reports, FT8, Guest Posts, Mobile, News, Portable, QRO, QRP, Travel

N2YCH: January POTA Travel in Frozen Alaska!

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Many thanks to Conrad (N2YCH) who shares the following field report:

Conrad’s January Alaska Activation

By: Conrad Trautmann, N2YCH

“Why would you go to Alaska in January?” is what everyone asked me.

I’ve wanted to see the Northern Lights for as long as I can remember. The best time to see the aurora borealis is between late August to late April in Fairbanks, Alaska. Days are short in January, sunrise is at 10:24am local time and sunset is at 3:38pm. It’s twilight before the sun comes up and after it sets so it’s not pitch dark, but it’s mostly dark for about 19 hours a day in Fairbanks at this time of year. Once I began researching, I learned that peak viewing times for the aurora are between 10p and 2a local time even with the extended darkness. Check aurorasaurus.org for more information.

So, the answer to the question is, “The odds are better to catch the Northern Lights in the winter.”

Cold weather and snow doesn’t bother me having lived in Syracuse, New York for ten years. I have experience with winter weather and driving. Fairbanks is one of the best places in the state to see the aurora since it is directly below the “Aurora Oval” and it has over 100 days a year when the aurora is visible. Except for January 12th through the 15th, 2024, when the sky had 98% cloud cover and it was snowing. Aurora viewing was not happening during my visit.

However, this trip was not a total loss by any means. There are things to see and do here, including activating parks! I activated three parks in three days, Denali National Park (K-0022), Chena River State Recreation Area (K-7228) and Creamer’s Field Wildlife Refuge (K-9697). I’ve heard stories from hams in Alaska that propagation can be spotty, that there can be total radio blackouts from solar flares and that bands we don’t usually worry about in the lower 48, like 20 meters, can be useless at times. I packed enough equipment and antennas to activate on any band from 40 meters to 6 meters, up to 100 watts using my Elecraft KX3 with the Elecraft KXPA100 amplifier. On the first day at Denali, I used the amp for the entire activation, but I realized at the end of the day that Thomas, K4SWL, who runs “QRPer.com” wouldn’t be too happy with a field report from “QROer.com” Conrad, N2YCH. To remedy that, I activated my second park using just my KX3, no amp. At K-7228, my first 11 QSO’s were QRP and the park was officially activated using only QRP power. I activated my third park QRO, read on and I’ll explain why.

[Thomas here: For the record, readers, I gave Conrad a Special Use Permit to mention QRO on QRPer! Ha ha! Of course there’s no problem going QRO from time to time!]

Back to propagation, I emailed one of the most active POTA activators in the area prior to my trip to get a sense of what to expect. I highly recommend doing this for anyone planning to travel somewhere and activate. Look at the POTA pages for the parks you want to activate and you’ll surely see a repeat activator with a Kilo award or many visits to those parks. They know the parks the best and also what to expect for propagation. They also share your passion for POTA and are usually very happy to help. The advice I received was that it would be difficult to make contacts on 20 meters and that watching the MUF (maximum usable frequency) charts would serve me well. (Check out hf.dxview.org) The activator said 10 meters would probably be the best band during daylight hours. He was exactly right. Even with QRO power, 20 meter reception in Alaska was noisy and my signal did not get out very far on FT8 watching the pskreporter.com spot map. I moved to 10 meters and quickly had a steady pile up. I stayed on the air until I depleted a 9ah and a 3ah battery I brought. What fun!

Okay, so for the QRP activation, I was at a trailhead parking area out near the Chena Hot Springs resort. Before the activation, I stopped and did the tour of the Aurora Ice Museum and took a dip in the natural hot springs. I do recommend the hot springs if you ever go to Fairbanks. It was -10F degrees when I was there, quite an experience.

Chena Hot Springs

I intentionally wanted to delay my activation from early morning to closer to sunset to see if operating during the evening gray line passing over would help improve the number of contacts I could get. The short answer is that it was worse…way worse. I went back to activating closer to sunrise on my third day and had similar results as I did the first day, much better. Sunrise wins.

The map above shows my initial ten QRP QSO’s from K-7228.

What really continues to amaze me is just how far my signal can reach with the portable equipment I was using. I brought the Buddipole so I could configure it as a vertical or a dipole. I tried it as a vertical on 20 meters on my first day and as I said, the reception was poor. The beauty of the Buddipole is that I could quickly reconfigure it to a 10 meter dipole. With the tripod, it’s roughly 10’ off the ground. There was no wind to speak of, so I didn’t need to guy it. If there was, I would have used a bungee cord to secure it to the car bumper or side mirror.

It breaks down and fits in the bag I bought with the Buddipole tripod and I tossed it into my checked bag on the plane. With the tripod and mast, it’s just a little too long for the carry-on bag. I could have brought a fiberglass push up mast and wire antennas in my carry-on, but I decided on the checked bag and brought the Buddipole to have as many options as possible. After all, I was traveling all the way to Alaska. Continue reading N2YCH: January POTA Travel in Frozen Alaska! →

Digital Modes, Guest Posts, How To, Mobile, News, POTA, QRP

K9JP: POTA QRV in a Ford Transit Connect!

11 Comments

Many thanks to Jeff (K9JP) who shares the following guest post:

Simple-for-me POTA activations

Jeff (K9JP)

This past year, I discovered POTA and the joy of activating parks. This part of amateur radio is very rewarding to me. I started activating parks in March, which means cold and possibly snowy days. I took the easy way and set up my POTA station inside of my car with the engine running to power the radio and the car heater creating warmth, but increasing my carbon footprint.

I soon recognized that had to be a better way.

I was using a magnetic-mounted ham-stick type of antenna on the roof of my car to make the antenna easy to use. I had problems getting my ham-stick antennas to resonate, did a little web research, and found that I needed to bond the coax feedline to the body of the car. I made up a pass-through coax connection using a chassis mount connector and a short length of one-inch ground braid that I had in my spare parts stash. I attached the braid to one of the back set floor bolts

Now the antenna was resonating and working well. For my radio, I used my backup ICOM IC-7300 with a power output set to 4 watts for QRP Fun. I can use all bands from 20 through 6 meters now.

My next change was to purchase a rechargeable LiFePo4 battery.. Looking at the cost per amp hours, I decided on a 100 Ah battery that offered a possible 2000 charge cycles. It should last for years with good care. With the large capacity of that battery, I can power the 7300 for many hours at QRP power levels and operate either FT8/FT4 or CW, and would also make high power possible if needed for some reason or other operating event. My experience so far has been I can operate from five parks per day and only need to charge the battery after the fourth day or about 20 activations.

I have recently purchased a Ford Transit Connect minivan to convert for my POTA Park mobile adventures. The van offered a better way to mount the antennas I use. It has a roof rack with cross-bars.

I modified an older Diamond roof rack mount to fit the wider cross bars.

Once I installed the coax bonding strap under the center-row seat I was ready to go.

I had also received a 40-meter ham-stick type antenna and thought I would give that band a go on my next park activation.  Again no joy, I could not get the 40-meter antenna to resonate. When I got back home, I made up a 1/2″ grounding braid strap long enough to bond or connect the roof rack mount to the body of the minivan. I covered this strap with dual wall adhesive lined heat shrink tubing.

This bonding strap is connected to the roof rack mount, runs under the side door weather stripping, and is terminated under the side door latch.

Now the 40-meter resonator was working very well.

How could I add 60, 80, or 160-meter bands?  Giving that some thought, could I try to create a sort of 1/2 fan dipole?  Yes, I could!  Through experimentation, I made up clamp-on elements for 60, 80, and 160-meter bands. Those can be attached or clamped on the quick disconnects I have on all my ham stick antennas.

I support the clamp-on elements by either draping the wire element over nearby shrubs or small trees or by just using a plastic step-on fencing post that I found at my local farm and home supply store. It only costs $3.00. These elements create an NVIS radiation pattern which helps reach out to interstate POTA hunters.

Inside the minivan, I place my portable LiFePo4 battery, 7300 radio, and my laptop for digital modes and logging.

I hope you will find this helpful. I believe this is a simple way to activate parks.

I now have 186 activations, from 23 parks, and 4800 contacts using 160 through 6-meter bands.  Many thanks to all I have contacted this past year and my goal for 2024 is to try and activate more Michigan, Ohio, and South West Canada parks using QRP power levels.

72/73 de Jeff K9JP

Antennas, Digital Modes, Field Reports, FT8, Guest Posts, News, Portable, POTA, QRP

N2YCH’s Top Band POTA Activation Field Report

9 Comments

Many thanks to Conrad (N2YCH) who shares the following field report:

Top Band POTA Activation Field Report

By: Conrad Trautmann (N2YCH)

November 15, 2023

In February 2023, Brian, K3ES, wrote here on QRPer.com about designing and building his own QRP portable random wire antenna he called the VK160 to work on 160 meters to make parks on the air contacts. This was in order to achieve his goal of getting the James F. LaPorta N1CC award where activating on 10 bands at 10 parks is needed. It’s not as easy as it sounds. As an avid parks on the air activator myself wanting to try activating on 160 meters, I built my own antenna based on Brian’s design and used it to get my first contacts ever at a park on the “Top Band.”

The Antenna

Brian used a 9:1 unun that he built himself in his design. Rather than build my own from scratch, I took a short cut and bought a QRPGuys 40m-10m UnUnTenna to use as the starting point for my VK160. Even though it says 40m-10m, it works on 160 meters, as you’ll see.

With shipping, it cost $36.00. It comes with all of the parts you need to assemble the antenna except for the wire. The main thing I liked about the QRPguys design was that the circuit board also doubles as a wire winder, so it’s all self-contained.

I sourced the wire from Davis RF and ordered 200’ of “POLY STEALTH – 26 AWG, 19 0.22000 44.00 STRAND COPPER CLAD STEEL, BLACK PE JACKET.” It cost $50 including shipping. The polyethylene insulation prevents the wire from knotting up. I measured out 144’ for the radiator based on Brian’s design and used the remaining wire as the counterpoise.

The completed antenna

I did a back yard test once it was all assembled and it worked great. For $86, I had created my own VK160. I encourage you to read Brian’s detailed design/build report here.

The POTA Activation – November 14, 2023

Now that I had completed building and testing the antenna, the next challenge was how to actually put it to use at a park. 160 meters doesn’t really come to life until dusk or after dark. In Connecticut, most state parks close at dusk. The park rangers clear the parks to close them at the best time to activate the band. However, there is one park nearby my QTH, the Stuart B. McKinney National Wildlife Refuge, K-0228, that has an annex called the Great Meadows Unit in Stratford with a nice parking lot that is not gated and has no posted hours. I arrived and set up at sunset, around 4:30 pm ET and operated from 5 pm until 6 pm. It gets dark here early in the Northeast US in November.

Another challenge is how to manage and string up 144’ of wire. Brian suggested an inverted V over a tree branch in his write up. There were no trees nearby, so instead I used a Spiderbeam fiberglass pole secured to my Jeep to get the feed point up in the air about 25 feet. I used RG58 cable from the feed point to the radio.

Spiderbeam fiberglass pole supporting VK160

Finally, I used one of my $3.00 Home Depot electric fence posts to secure the far end to keep it tight and up in the air and set up the antenna as a sloper. I laid out the counterpoise on the ground under the sloping wire.

By the time I had all of this set up, it was getting dark. I connected my Elecraft KX3 to the other end of the RG58 cable and to my surprise and delight, I was already receiving stations.

My KX3 has a built-in ATU and one tap of that ATU button and it tuned to 1.0:1. I started the activation right at 5 pm local time and in about 15 minutes, I had six QSO’s on 160 meters.

The PSK Reporter map showed me being received by stations on the dark side of the gray line in the Northeast. It was pretty much what I expected for QRP power on the low frequency. Then, the next ten minutes things were quiet. It appeared I had gotten everyone who could hear me.

Since this is a random wire antenna, it should work on all bands so I decided to test it on 80 meters. Again, the KX3 tuned right up and I got six more QSO’s. I was surprised to see Del, N2NWK from Washington, DC pop up on JT Alert. I have a an alert set for stations calling CQ POTA. Del was also at a park. I called and he answered and we ended up with a park to park. Anyone who knows Del knows that when you hunt him, he’s usually activating at a two-fer, at least. When I checked my hunter log afterwards, I saw four parks listed from him (a four-fer?).

At this point in the activation, I had gotten the ten QSO’s that I needed to call the park activated. I thought, let me try the VK160 on 60 meters. I re-tuned the KX3 and got five more fast QSO’s. The antenna worked great.

Before I packed up, I decided that I really wanted at least ten contacts on 160 meters, which was my original goal. I went back to 160 meters, now close to an hour later than when I began the activation, and easily added five more new QSO’s to the log. Maybe propagation had changed the later/darker it got or some new hams were on the band who weren’t on earlier, but I was satisfied to have gotten more than 10 on the top band.

The Results

Here’s how I did. Green pins are QSO’s on 160 meters, blue pins are 80 meters and the pink ones are 60 meters (click image to enlarge).

Equipment List

Conclusion

The “Top Band” activation was a success! The VK160 worked flawlessly, thank you Brian, K3ES for posting your design and providing the inspiration to activate on 160 meters.

My POTA “My Stats” page now shows 11 digital QSOs on 160 meters that I didn’t have before. I love conquering new challenges and given the challenge of going mobile with an antenna that will actually work and tune up on that low of a frequency at a park that won’t make you leave at sunset, well… that was quite an accomplishment!

Thank you to the 22 hunters (11 on 160 meters) who helped make it a success, including my friend Del, N2NWK in Washington, DC.

Conrad, N2YCH and Del, N2NWK
Accessories, Digital Modes, FT8, News, QRP

BG6LH Designs a Board for Integrated Yaesu FT-817/818 FT8 Operation

10 Comments

Many thanks to Cao (BG6LH) who writes:

Hi, Thomas!

I would like to share my QRP FT8 kit for Field Operation.

A long time ago, I was seeking the most lightweight QRP kits for FT8 field operation. My goal was to have just one radio, one antenna, one phone, without too many cables, boxes, etc.

Finally, I designed a PCB. It is a Bluetooth DIGI Adapter and can be mounted on the rear panel of my FT-818.

Just plug it to the DATA and ACC jacks. It can be powered by ACC jack’s 13.8V Pin.

It works well with FT8CN, an android FT8 app.

Now, my dream has come true!

My Antenna was a so-called GAWANT, designed by JF1QHZ, I guess it’s a simple Vertical EFHW. I built it with a 1.2 meter rod.

It’s working on 7~28MHz bands, not very efficient, but so small and portable.

For FT8 QRP POTA, field operation, all of these components can be put in a small bag, and deployed in minutes.

I shared my PCB design on Github. If anyone wants to modify it, you are welcome to do so!

https://github.com/BG6LH/FT-81x-BT-DIGI-Adaptor

Thank you for sharing this, Cao. This is absolutely amazing and an incredibly clever design! I suspect a lot of FT-818/817 enthusiasts will make this same build via your design!

Thank you for reaching out and for sharing your work with the QRP community! 

Digital Modes, Field Radio Kits, Guest Posts, News, Portable, POTA, QRP

Field Radio Kit Gallery: KI7URL’s (tr)USDx Ultralight Portable Kit

3 Comments

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!

73,
Jim
KI7URL

Equipment: