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
Thank You Jeff! Great pictures and so helpful. Wish i had known about your excellent ideas years ago.
Armin VA3YB
Thank you, Armin
About 15 to 20 years ago, I had another van on which I mounted an antenna ball mount on the roof just above the interior ceiling light. Sealed the mount from the outside with silicone seal, and attached the smaller Tarheel antenna. That was an amazing antenna for HF mobile. I have not owned another vehicle (all leased) since then, that I could drill a hole into the roof or side.
Now, I am enjoying QRP from the many different state and federal parks.
Jeff-
You’ve discovered the need for bonding the coax feed to the vehicle frame as well- good deal. It’s really making a difference for me.
I admit to a tinge of envy about the Ford Transit. We’re retired now, and it’s not in our budget. All the same, have a blast with that new vehicle, and best wishes for many successful POTA activations! 73- K1SWL
Nice setup, Jeff. Simple but effective! So many people miss or skip the vehicle bonding part and end up disappointed.
It is a work in progress, but I have a 2012 low-mileage Ford E-350 full-size van. I enjoy SOTA, POTA, and camping so it is being configured for POTA, base camp, and camping.
Thank you, Dave and Tim
The transit is a used 2022. It cost the same as the SUV I was leasing. My wife likes it because she finds it easier to get in and out than the SUV. I hope this summer to configure the Transit into a simple overnight camper with an air mattress, sleeping bag, pillow, and Portable RV toilet. Then I can drive to and operate from different parks. No more lease miles to worry about and if I need to drill a hole it will be O.K. as well. I just turned 70 years old, so I think will be my last adventure van. Thanks to all of you have have helped and motivated me to do this. Much appreciated. I will report back with some of my adventures down the road. 72/32 de Jeff K9JP
I have several hamstick antennas. I primarily drive around with the 20m flavor and make CW and SSB contacts every single day, regardless of band conditions. The trick is you got a hard mount those things and then they are beautiful antennas. I have two SO239 hard mounts with adapters for the hamsticks. Mobile rig is a IC-705 and a 30 watt aftermarket amp. No tuner. Literally is my favorite rig/setup I’ve ever had operating mobile. It’s so good it makes me miss my hour plus commute that I used to have in my younger days.
73
Scott
W4PIC
risking being a rude question: what is a hard mount?
Hello, Armin
If you have not received a reply to your question of “what is a hard mount”, my guess is a PL-259 to 3/8 x 24 adapter.
CB Antenna Connector Adapter 3/8 x 24 Threaded Antenna Mount to UHF PL-259 (SO239 Mount)
Thanks Jeff. I take my IC7300 to the car like you do. I do ok with a alpha coil and 5′ whip on “hard mount” drilled into the roof. But, i bet i will do better with your coax ground connection idea.
Cheers, Armin va3yb/w4
Hi Jeff, great post, as an
FT8/ft4 afficianado, are you using a GPS dongle to handle the timing or is there ready access to Wi-Fi where you are activating. Here in the rural area of Nova Scotia, access to WiFi can be a challenge.
Thanks again and look forward to reading about your next adventure. Vy 73, Rick VE1RNM
Greetings, Rick
I do not use a GPS dongle. I use my MacBook Air laptop which I connect to the internet once before I leave the house. I feel the MacBook keeps time better than the PC laptop I also have used. The PC would require me to connect to my cellphone about every two to three hours. It could have been the CMOS battery that powers the clock when it is offline. The PC laptop was about 7 years old at the time. I would assume someday my Macbook will do the same. There is no wifi to connect to at any of the Parks I have activated so far. Sometimes I also have no cell signal as well. Connecting to my cellphone as a hotspot to update the time sync is the only thing I can do if needed.