Tag Archives: Fort Dobbs State Historic Site (US-6839)

Field Report: Testing the bhi Dual In-Line with the (tr)uSDX, making a big blunder, and P2P with Teri!

On March 30, 2022, I took my factory-assembled (tr)uSDX transceiver on a POTA activation at South Mountains State Park.

It was a “test flight” of sorts since I’d only had the (tr)uSDX for a few days and had not taken it to the field.

I wrote up an assessment from that initial POTA activation mainly to give other potential (tr)uSDX owners an idea of how well one of these super-affordable radios might perform.

Difficult to critique

It’s difficult to critique a 5 band HF radio that you can purchase as a kit for less than $100 and fully-assembled and tested for less than $150…shipped!

On the one hand, I think it’s one of the most amazing portable HF radio innovations of the past decade. It simply blows my mind that the developers (DL2MAN and PE1NNZ) could make this modest radio hardware do so very much. It’s truly a triumph of engineering and a fun little radio.

On the other hand, this isn’t a high-end radio, so we can’t expect performance like we’d see in an Elecraft, Icom, or Yaesu field radio, for example. I never expected this, in fact, but was very curious if the performance would be “good enough” for POTA or SOTA.  So many had asked me about buying a (tr)uSDX as their dedicated POTA radio.

I found using the (tr)uSDX for POTA was actually quite fun, and I certainly achieved my goal of activating a POTA park with it.

So yes, it’s good enough!

That said, I haven’t reached for the (tr)uSDX to do POTA or SOTA since last March because I prefer the performance characteristics of my other radios.

My biggest complaint, frankly, is that the audio fidelity is pretty poor. The noise floor of the (tr)uSDX is higher than most HF radios and audio amplification is very basic. I notice a lot of electronic noises (pulsing, etc.) in my unit. I find it a bit fatiguing to listen to for long sessions with my headphones. The internal speaker isn’t really a viable speaker for doing an activation–it’s more akin to an emergency speaker, if anything.

When plugged into an external amplified speaker, the audio is much improved. The pops and internal noises are still there, but it has better overall fidelity and the volume can be raised enough to hear weak signals (this can’t be easily done via the internal speaker).

It struck me that a DSP device might clean up the (tr)uSDX’s audio and noise floor a bit.

Enter the bhi Dual In-Line DSP filter

Sometime during the beginning of the pandemic, I reached out to bhi Noise Cancelling Products and asked if I could test one of their DSP units as a loaner. I’ve always felt that bhi manufactured the best DSP products in the amateur radio market.

At the time, I wanted one of my friends and contributors on the SWLing Post blog to test the bhi unit and see if it might help out a QRM situation that popped up at his QTH. I thought it would make for a great evaluation since I have little to no QRM at my home.

Graham, at bhi, kindly sent me a unit–the Dual In-Line Noise Eliminating Module–and as I prepared to forward it to my friend, his noise was no longer an issue. I can’t remember the details now, but there was no need to send it to him.

I notified Graham that I would like to test it myself, but that my plate was so full it would take time. What ended up happening, though, was I completely forgot about it due to a busy family life at the time.

I re-discovered the unit this year and spoke (apologized) to Graham at the 2023 Hamvention. Of course, he had no issue at all and was very forgiving. He’s a great fellow.

I thought pairing this bhi DSP unit to the (tr)uSDX would be a great way to, perhaps, cut down on the listening fatigue.

Fort Dobbs State Historic Site (K-6839)

On Wednesday, July 5, 2023, I had an opportunity to test the (tr)uSDX/bhi pairing at Fort Dobbs State Park. Continue reading Field Report: Testing the bhi Dual In-Line with the (tr)uSDX, making a big blunder, and P2P with Teri!

POTA at Fort Dobbs: Testing a BCI filter and depleting a battery!

Friday, March 17, 2023 was a dreary, rainy day.

It was the sort of day made for reading a good book by the fireplace or…in my case…activating a park!

I don’t let rain stop me from playing radio in the field. I carry a rain fly in my car pretty much all of the time so if push comes to shove, I can create a dry space to play radio.

That said, a number of parks I frequent have large covered picnic shelters, so why not use what’s already there?

That particular Friday, I had one particular park and one particular goal in mind.

G106 + BCI Filter

As I mentioned in a post this weekend, I purchased and built a K9DP BCI Filter Kit.

If you’d like to see photos of the build, check out this post.

I built this BCI filter specifically to pair with the Xiegu G106 transceiver. Why? Because the G106 is prone to overload if you’re anywhere near an AM broadcaster.

The last time I visited Fort Dobbs State Historic Site (K-6839), a local AM broadcaster bled through the audio of the G106. I was able to complete the activation without any issues at all–in fact, it was a very successful activation (read the report here).

Still, I did feel that the receiver was a bit less sensitive due to the broadcaster overwhelming the front end of the radio.

That Friday, I wanted to pair my Xiegu G106 with the new in-line BCI filter to see if that might mitigate the interference I experienced before.

Fort Dobbs State Historic Site (K-6839)

After arriving at Fort Dobbs, and before taking my gear out of the car, I made my way to the park office (in the log cabin at the end of the sidewalk above) and asked for permission to use their picnic shelter. Continue reading POTA at Fort Dobbs: Testing a BCI filter and depleting a battery!

Giving the Xiegu G106 a thorough workout at Fort Dobbs!

On Thursday, February 9, 2023, a rare opportunity opened up for me: a 3.5 hour activation window–!

I was visiting and helping my parents in Catawba County, NC, so considered the park options, almost all of which are within a 35-45 minute drive.

I thought about fitting in two shorter park activations that day, but it has been so long since I’ve had the opportunity to simply hang at one park and play radio for more than an hour, I chose the extended activation option.

Although the forecast was for clear skies that day, a front was moving through that afternoon and the skies were overcast with gusty winds. I could tell rain was a very real possibility, so I chose a site with a picnic shelter to make things a bit easier.

Fort Dobbs State Historic Site (K-6839)

Fort Dobbs was a no-brainer: not only was it the closest park (thus less travel time eating into my on-air time), but the staff there are very POTA-friendly, the site is quiet, and they have an excellent shelter that I suspected (due to the dodgy weather) would be unoccupied.

When I arrived on-site, I checked in at the visitor’s center to make sure the picnic shelter hadn’t been reserved. Fortunately, they said I could have the shelter all to myself!

I had a number of radios in my car and decided en route that I would use the Xiegu G106 once again.

I packed the G106 in a waterproof Husky radio gear box I keep in my car trunk/boot. I grabbed it and my Spec-Ops EDC pack and carried it to the picnic shelter.

My plan was to pair the G106 with MW0SAW’s 40 meter EFHW antenna.

This would give me two resonant bands (40 and 20 meters) so there’d be no need to connect an external ATU. Continue reading Giving the Xiegu G106 a thorough workout at Fort Dobbs!

QRPp: Activate a park with ⅒ of a watt–? I had to at least try!

In my last published field report, you might recall that I successfully activated a park using 500 milliwatts or ½ of a watt. I was so surprised by the results of using this QRPp power level I immediately made plans to push the power level even lower during my next activation.

Let’s face it, I was drunk with a lack of power!

QRPp

After my last field report, there were quite a few questions about the term QRPp and what it means. To be honest, I’m not sure if there’s an “official” definition, but here’s what is widely accepted as QRP power categories:

  • QRP: 5 watts to 1 watt (for some contest 10 watts = SSB QRP)
  • QRPp: Less than 1 watt to 100 mw
  • QRPpp: Less than 100mw

I don’t own a field radio that allows me to lower the output power to QRPpp levels. In fact, few of my radios actually allow me to lower power below one watt.

 

My Elecraft radios, however, do allow me to lower power output to as low as 0.1 watts or 100 milliwatts.

The plan

On Wednesday, December 7, 2022, my travel schedule shifted and it opened up the entire afternoon to play radio.

A rarity indeed!

It was very rainy and foggy that day and I didn’t have my ENO rain fly with me, so I decided to visit a park with a good picnic shelter to keep me, an my gear, nice and dry.

Fort Dobbs State Historic Site (K-6839)

I had four park options with covered picnic shelters within a 45 minute drive. I decided that I would try to activate Fort Dobbs State Historic (since it had been a couple months since I’d visited) and Lake Norman State Park would be my back-up plan.

Fort Dobbs is a small park, so I called in advanced and asked for permission to do the activation and also asked if their picnic shelter was reserved.

The rangers there know me, so the phone call was pretty quick–no need to explain POTA nor my motivations. They told me that on rainy/foggy December days they have so few guests that I was welcome to use the picnic shelter or even the entire park if I wished (perhaps an ideal time to erect a Rhombic antenna–okay, just kidding!).

The Dobbs park rangers an volunteers are the best!

Setting up

On the way to the site, I decided that I would deploy my MM0OPX end-fed half-wave I’d cut for 40 meters.

I needed to make the most of my 100 milliwatts, so I figured the MM0OPX EFHW would be the best antenna for the job. Continue reading QRPp: Activate a park with ⅒ of a watt–? I had to at least try!

POTA with the Icom IC-703 Plus: Working a serious SWR problem first, though!

If you’ve been here long, you’ve no doubt noticed that I have a sizable collection of QRP radios I take to the field.

Although I have some favorites, I try to rotate all of my radios in the field and even pair them with different antenna combinations as much as possible. If I only owned one field radio, I’d shake things up by pairing my one radio with different antennas deployed different ways during my POTA/SOTA activations.

I get a real thrill out of testing different combinations, actually, and I feel like it keeps me on my toes because I don’t get too comfortable with any one setup in the field.

No doubt, using a wide variety of radios gives me a more informed perspective when beta testing or evaluating new radio models.

That said, there is one radio in my collection that has been overlooked too many times: my Icom IC-703 Plus.

Many of you have noticed this, in fact.  I’ve gotten several emails and comments asking, “So Thomas…when are you taking the 703 out again–?” 🙂

When I purchased the ‘703 from my buddy Don a couple years ago, I imagined taking it to the field very regularly. I always thought it was a cool little radio and with its built-in ATU, it’s quite compact for a tabletop-style rig.

Thing is, each time I’ve taken it to the field, I’ve had issues with the electronic keying that I did not have when using it in the shack. It’s quite sensitive to RF, so end-fed antennas seem to create unwanted dits and dashes in the keyer.

The simple fix, I hoped, was simply using an in-line common mode choke to keep the RF away from the radio. Thing is, the IC-703 has an SO-239 antenna port and two of my common mode chokes are BNC. I meant to purchase a BNC-to-PL-259 adapter at the Shelby Hamfest, but picked up the wrong item (I should have been wearing my glasses).

Then I remembered that my Chameleon 50′ RG-58C/U cable not only has an integrated in-line choke, but also PL-259 connectors. This could work! Continue reading POTA with the Icom IC-703 Plus: Working a serious SWR problem first, though!

QRP POTA at Fort Dobbs: No antenna? No problem!

I’m a pretty organized field radio guy if I do say so myself.

In all of the hundreds of field activations I’ve attempted since the days of the National Parks On The Air (NPOTA) program, I’ve only arrived on site two or three times and discovered I was missing a key component of my field kit.  Out of those times, only once do I remember that the missing component prevented my activation (it was hard to power my radio without a battery and power cable). The other times, I was able to improvise.

As I mentioned in this two-parter series, I tend to build two different types of field kits:

  • one that’s fully self-contained (like the MTR-3B kit),
  • or one that’s modular, where component families (transceiver, antenna, power, etc) are in their own packs and can be moved from pack to pack.

I always prefer having dedicated field kits, but they’re pricey because they require a dedicated antenna, battery, radio, key/mic, earphones, pack, connectors, and sometimes even their own throw line.

I assemble modular kits around a particular radio and antenna system prior to leaving the QTH to go on an activation. I have a method for doing this which prevents me from leaving stuff behind.

Save this time…

On Thursday, April 7, 2022, before leaving the house for a quick overnight trip, I grabbed my SOTA pack and disconnected my Elecraft KX3 from the KXPA100 amp in the shack.

My pre-side rails KX3 in the shack.

My KX3 is used a lot in the shack–along with the Mission RGO One and Ten-Tec Argonaut V–it’s one of my staple rigs at the QTH. I didn’t think I would have time to complete an activation on this quick trip, but if I did, I wanted to use the KX3. I also grabbed one of my pouches that contained a 12V battery, distribution panel, and power cord.

Also inside the pack was my Elecraft KX2 kit. It was in there from a previous activation, so I just left it in the bag.

When a window of opportunity for a quick activation opened on Friday, April 8, 2022, I grabbed it. I didn’t have time to go far afield, so I chose to activate the closest park to where I was running errands that day.

Fort Dobbs State Historic Site (K-6839)

As I was driving to the site on I-40, it dawned on my that I might have forgotten to pack an antenna.

Not a good feeling, but I was only 10 minutes from the park, so there was no turning back.

You see, a couple days beforehand, I did a bit of an antenna inventory at the QTH–I took all of my antennas out of their packs, checked them over carefully for any damage or fault points and  made notes.

I normally keep a 20M EFHW antenna in my KX2 field kit, but I remembered that also I removed it during the inventory.

Once I arrived at Fort Dobbs, I opened my SOTA pack and confirmed that I had no antenna. Not a one.

I kept a clear head and realized that if I wanted to complete the activation, I needed to do one of two things:

  1. Search the car in case, somehow, I had a spare antenna floating around in there. Unlikely, but I’d feel like a fool if I aborted an activation with an antenna in the car.
  2. Go to a nearby hardware or dollar store and find some cheap wire.  The KX3 has a brilliant internal ATU to match pretty much any wire I connect to it.

So, I searched the car. Continue reading QRP POTA at Fort Dobbs: No antenna? No problem!

POTA Field Report: Fort Dobbs, 5 watts, and speaker wire

After making my first activation of Fort Dobbs State Historic Site, I knew I’d be back in short order. It had all of the things I love about a great POTA site: it’s accessible in my weekly travels, has tall trees, a huge shelter, and friendly park rangers. Plus, it’s chock-full of history.

Does it get any better?

Fort Dobbs State Historic Site (K-6839)

On Wednesday, August 25, 2021, I stopped by Fort Dobbs for a quick activation.

Even though I arrived only shortly after the park opened and I was obviously the only guest there, I checked in at the visitor’s center to get permission to do the activation.

Not only did they grant me permission, but they also allowed me to set up in their main covered picnic area.As I mentioned in a previous post, I believe you should always ask permission at small historic sites like Fort Dobbs.  For one thing, I want the staff to know where I am and what I’m doing. Unlike vast state and national parks, their spaces to set up may be more limited and the last thing you’d want to do is set up shop in a space where they plan to do a scheduled outdoor presentation in period costume.

 

In addition, some historic and archaeological sites  may have restrictions on the types of antennas you employ. I’ve known of some, for example, that require fully self-supporting antennas that need no trees nor no stakes in the ground.

The folks at Fort Dobbs couldn’t be more friendly.

On the air

I decided I’d pull out the trusty 28.5′ speaker wire antenna and see how well it might perform while paired with the mAT-705 Plus and Icom IC-705.

Set up took all of three minutes.

With super lightweight antennas like the speaker wire antenna, there is rarely a need to tie off the end of the throw line to hold the antenna in a tree and in position. Unless there are strong winds, the weight of the throw line itself will hold it in place. Deploying the antenna and connecting it to the ATU and transceiver may have taken me two minutes.

Relying on trees can be a little unpredictable; some sites may have trees that are too short, some with branches that are too high, some that are too dense with branches, and/or trees may not be ideally situated for a field activation.  When things aren’t ideal, it might take much longer to deploy a wire antenna in a tree. This is one reason why so many POTA and SOTA ops choose to bring their own collapsible support–it gives them a degree of predictability when setting up at a new site.

Fortunately, at Fort Dobbs, there are numerous trees that are ideally situated for effortless field deployments.

Gear:

I hopped on the 40 meter band and started calling CQ.

Fortunately, propagation was in pretty good shape, and I worked a string of contacts.

It was nice to experience a more “normal” activation where propagation wasn’t completely in the dumps.

I eventually moved up to the 20M band and did a little hunting before finally packing up.

All in all, I made eleven contacts–just one more than the 10 required for a valid POTA activation.

I could have stayed and played radio for a much longer period of time–and I was tempted for sure–but I chose to fit in one more activation that morning at nearby Lake Norman State Park. So I packed up and moved on.

QSO Map

Here’s the QSO map of my contacts at Fort Dobbs:

Video

I made another real-time, real-life, no-edit video of the entire activation as well. You can view it via the embedded player below, or on YouTube:

I didn’t work any DX at Fort Dobbs, but I was super pleased with the speaker wire’s performance using only 5 watts of output power. I imagine if I would have stayed on the air for another hour or two, I could have worked a couple stations in Europe. It was a tad early for much activity on 20 meters.

Thank you!

Thank you for reading this field report and a special thanks to those of you who are supporting the site and channel through Patreon and the Coffee Fund. While certainly not a requirement–my content is always free–I really appreciate the support.

If you can, find some time to chase or activate a park or summit near you! Or, if you have an opportunity, just take your radio outdoors, hop on the air, and have some fun. It’s good for your soul!

And a friendly reminder: you don’t need a fancy radio or fancy antenna. Use what you’ve got. Pretty much any transceiver you’re willing to lug to the field will work. And antennas? As you can see, even $4 of speaker wire conjures up some serious QRP magic!

Cheers & 73,

Thomas (K4SWL)

POTA Field report from Fort Dobbs State Historic Site

It’s funny: when I started my POTA journey in earnest during February 2020, I plotted out all of the state parks in the part of western North Carolina where I travel the most.

At the time, POTA had only a wee fraction of the community it does now and many of the parks and game lands were still ATNOs (All-Time New Ones)–parks that had never been activated. Fort Dobbs was still one, in fact, and I had marked it on my POTA game plan spreadsheet.

My mission back then was to rack up unique-to-me parks as I explored the region; in doing so, I ticked off quite a few ATNOs. It was fun!

I focused on parks a little further afield first. This provided me with a sense of adventure and travel during the first round of Covid-19 lockdowns.

At the end of 2020, I realized I had never activated Ft. Dobbs State Historic site which was, ironically, one of the lowest hanging fruit sites around. It’s only, perhaps, 30 minutes from where I travel each week.

I suppose Fort Dobbs has been “out of sight, out of mind” until I saw a tweet from Andrew (N4LAZ) who activated Dobbs on August 6, 2021. I mistakenly assumed that the only spots to set up on site were around the periphery of the parking lot. This time of year, in the middle of the hot and humid summer? I’m less enthusiastic about open parking lot activations.

Andrew mentioned that the site actually has an excellent covered picnic area where he was allowed to perform his activation.

That’s all I needed to know!

Fort Dobbs State Historic Site (K-6839)

On Tuesday, August 10, 2021, I traveled to Fort Dobbs State Historic Site and quickly found the covered picnic area Andrew had mentioned. It was, indeed,  ideal for POTA!

Continue reading POTA Field report from Fort Dobbs State Historic Site