POTA Adventures
This month’s article will highlight a few POTA adventures that I went on earlier this year. POTA hunting and activating have been a large part of my operating activities for the last two and a half years. In fact, as I am writing this, we are trailer comping at Caddo Lake State Park which I just activated September 25thand 26th . I plan to activate several other close by POTA entities while here later in the week.
Roger, K0YY got me started when he organized a POTA outing to Mission Delores State Historic Site (POTA Reference K-6582). AA5HH, W5NXK and KB5EDR also activated and we had a great time even though it was cold and damp. It has been pretty damp here at Caddo Lake State Park, but I sure wish it was a little colder. The high was “only” 91° F today, so I guess I shouldn’t be complaining with how hot this summer has been! While activating the park last night, I used my IC-7100 at 75W into a Wolf River Coil on 20M and made contacts as far as Chile and the Azores.
While not on the POTA leaderboards, I spend a fair amount of my operating time “chasing parks”. Lately, I have been using the POTAPlus browser extension (see August newsletter) to highlight parks that I have not hunted before and boost my hunter score. I also operate all of the major modes that activators use (SSB, CW, digital) to boost my totals. I am actively learning CW using the CW Ninja YouTube video series (CW Ninja) so the vast majority of those QSO’s are “PC-assisted”. That is, I use a decoder to verify that I received correctly. Initially, I also used PC sending (via ACLog), but lately, I have been sending my replies using an iambic paddle.
For POTA activations, I have been much less active, although with the cooler weather coming, I plan to get out more. This summer, my activations have been in the truck, replacing my dual-band antenna with an NMO to 3/8-24 adapter and a hamstick. I operated QRP digital from the driver’s seat using the QRP Labs QDX transceiver and notebook computer. I drove a 3.5-hour loop hitting 4 parks out of Waxahachie, TX as shown on the first map below. The goal was to get 4 quick activations and meet my wife back in Waxahachie for dinner. Despite using only 5W and truck-mounted hamstick, the 59 QSOs spanned the entire US and reached into southern Canada on 20M in the early afternoon (see second map below). These activations could have also been done using CW. However, for SSB I would want to use a more powerful rig.
I first activated Mission Tejas State Park in March of this year. When I noticed that remnants of El Camino Real del los Tejas National Historic Trail were visible in the park, I decided to activate a “twofer”. The marked portion of the El Camino Real is not in any of the developed areas, so this would involve a short hike and setting up in the field. POTA rules require that your entire “station” be within 100-feet of a linear entity such as a trail and on public land. That means that your antenna / coax, rig, battery, PC etc. must all be within 100-feet to be a good activation.
Note: Route for POTA Rove to K-2998, K-3004, K-3039 and K-3032 (park names in the map route listing)
Note: QSOs made on POTA Rove to K-2998, K-3004, K-3039 and K-3032
Note: Operating position in Mission Tejas (K-3040) and El Camino Real (K-4568)
I assembled my kit and made the second trip to Mission Tejas in April 2023. You can see the operating position in the photo directly above. For this activation I used the 5W (tr)uSDX transceiver. It is the orange box sitting on the PC. The (tr)uSDX does not include a built-in sound card, so a USB sound card and audio cables are needed to operate digital with it. The (tr)uSDX does have USB CAT control to interface with common digital software. The green box is a 6A-hr LiFePO4 battery that would run the (tr)uSDX for ~12 hours at a 50% duty-cycle.
For this activation, I chose the KM4ACK QRP 40M EFHW (End Fed Half Wave) antenna. The KM4ACK antenna is an easy to build kit and very lightweight. It is resonant on 40M, 20M, 25M and 10M, so a tuner is not needed for those bands further saving weight and cabling that can be easily left at home. I carry 25-feet of RG-316 lightweight coax to connect the antenna and rig when field-portable. Some QRP rigs have final RF amplifier transistors that are sensitive to poor SWR, especially when impedance is less than 50Ω. So, an antenna analyzer or some sort of SWR measuring / indicating device is necessary in the
kit. QRP-specific SWR bridges often include an attenuator to limit the portion of rig power supplied to the antenna to reduce the likelihood of “blowing” the finals. (The power not sent to the antenna flows through a 50 Ω` resistive load.)
An arborist throw weight with line and some guy rope completed the kit. An appropriate tree stood near the downed pine used for operating, so I was able to get the antenna up in a sloper arrangement with the high end at about 30-feet and the low end staked to the ground.
This activation demonstrated that you have to be ready for anything when operating in the field. After getting the antenna up and verifying the SWR, I fired up the PC and setup wsjt-x for the (tr)uSDX. CAT control worked fine, but the rig would not key when a software PTT command was issued. So there I was like a bump on a log wondering what the heck am I going do now. Well, I watched the wsjt-x timing carefully and noted that transmission started (as expected) every 15 seconds and ended after 12 seconds. (The additional 3 seconds are used by the software for decoding the received signals.) So, I manually keyed the rig when wsjt-x initiated the tone and released the PTT button after 12 seconds. It worked flawlessly. I made 20 contacts in 57 minutes, completed my hike in two-fer activation and had a very satisfying day!
Source PDF: 202310 – POTA Adventures
