Antenna on John Flinchbaugh KD3EE

T2LT Flowerpot Antenna

Tue, 17 Feb 2026 00:00:00 +0000

I’ve been curious about the T2LT “flower pot” antenna for a while. It’s fed from the bottom and attached to a sturdy PVC pole. I can easily hoist it into a tree, and it has a low wind load, so it could go on top of a flag pole again.

I built it at the SPARC Elmer night from some 75-ohm TV cable I had laying around. I taped and cable-tied it to a thin bit of PVC, and I adapted the feed point from 75ohm TV cable connector to SMA. I had built it long to allow tuning, but it tested to be just about right for 146MHz when I put the VNA on it.

choke on t2lt

t2lt installed

Fixed Slim Jim

Wed, 11 Feb 2026 00:00:00 +0000

The Slim Jim in the tree wasn’t working, so my APRS radio had gone quiet. I started testing with the nanoVNA before going out in the cold to check the connections. I found the lead inside was not passing any signal. The connector at the radio was pulling off the cable, so I could push it back together and re-crimp it. I got away with the easy fix.

985 Workbench: 2026-01-26

Mon, 26 Jan 2026 00:00:00 +0000

Winter Field Day

My Week in Radio

Winter Field Day
- I logged for CW ops and listened along
- I could hear 2-3 characters at a time

Others

W8CRW, CR:
- Field Day
WA3VEE, Ron:
- Field Day
  - operated most
  - worked N3FJP, author of the software
  - W1AW
  - W2AEW see on youtube
  - worked with Kianna
W3KZG, Scott:
- field day trailer worked out great
KB3PZY, Al:
- first field day
- Thanks Harvey for mentoring
- 30 some contacts
KB3ILS, Keith:
- antennas up at the field day site
- got to WFD early
- laptops, network, power worked great
- 450-475 contacts made
- SKCC
  - PR on 6M CW
  - Alaska on 15M CW
WA3KFT, John:
- WFD with another club, 75M
  - didn’t hear anyone in the afternoon, all noise
  - early evening it lit up
KC3OOK, Bill:
- simplex net
- welfare net
NA3CW, Chuck:
- welcome Al
- antenna install for WFD with lots of people
- “how to cut a dipole the second time, every time” worked pretty well
- used Joe’s tuner with 100W testing
- PMAM pre-net
AF3Z, Jim:
- SKCC month ends on saturday
  - coordinating SKCC ops, had enough of it :)
  - worked 240 contacts with special callsign
- worked WFD with cornwall station
  - proved total lid
    - operated a Elecraft K3 on 40M
    - heard W3R, but couldn’t get an answer
    - K3 needs VOX enabled for CW, so it wasn’t transmitting
    - quit for the morning
    - realized much later about VOX
AA3LH, Leon:
- winter field day at home: 40M and 80M *** Questions
KD3EE, John:
- What was the problem with the 80M antennas and that radio that rebooted?
- How significant is the dipole arrangement (flat vs inverted-v) to multi-station operation?
- W3KZG, Scott:
  - originally thought it was RF
  - switched radio to AC-DC power supply, and then the radio was fine
  - trailers battery may not have kept up with the severe cold
  - new radio couldn’t tolerate voltage drop, but older radio was ok
  - LiFEPo battery struggles under 30F
  - CW dipole showed high SWR at one spot, still needed to be investigated more
- WA3VEE, Ron:
  - when the weather is better, Ron will run a complete analysis on each antenna on the site.
  - we can talk inductance and capacitance then
  - there seems to be an RFI problem from a power transformer insulator up there as well
- KB3ILS, Keith:
  - 80M dipole cut for sideband worked well
  - 40M CW in the corner may need some work
  - 1 beam was pointing at the 80M dipole, so likely caused lots interference
  - it’ll be good to analyze when no one transmitting
  - one 40M dipole may be close to noise.
  - some experimenting to do
  - we still got lots of 40M contacts
- NA3CW, Chuck:
  - power-line interference has been an ongoing issue
  - Chuck has a small moxon for 137MHz that will be good paired with AM on his HT to search for the noise source
    - worked to find a bad pole in his neighborhood
  - inverted vs flat dipole
    - dipoles end to end have very little radiation off the ends.
    - inverted-v antennas would have seen each other on the ends
    - analyzers work with very low signals, so would have totally been skewed by nearby QRN and TX
- KB3ILS, Keith:
  - Chuck, let’s build a dipole curtain array for field day.
W3MFB, Mike:
- HF vertical can have a ground plane, even in the air or on the ground? They help control common-mode current? Why use them?
- WA3VEE, Ron:
  - the ground plane is the other half of your antenna.
- WA3KFT, John:
  - Has the Amtron A99 on a tower without the ground plane kit, but has a TV mast below it on the tower, so may be serving the purpose.
- W3KZG, Scott:
  - IMAC 2000 antenna, 50 ft in the air without the ground plane kit. The galvanized steel mast underneath it served as the ground.
  - AMTRON 99 came with it, so he installed it. It looks cool.
- AA3LH, Leon:
  - Used tuned hamsticks in Colorado, and put out lots of radials.
- KD3EE, John:
  - the computer and radio going wonky (touchpad, USB, etc) always remind me when I need to add radials to my vertical antenna.
- W3MFB, Mike:
  - With the IMAC, he knows he needs the ground plane kit as it gets higher in the air.
  - His is grounded to a gas pipe, so it seems to work pretty well, and he’s gotten to Australia.
  - Also has lots of coax to absorb it.
  - Has gotten to Australia with it.
KD3BPI, Simon:
- He’s planning for antennas on the house, 2 stories, walk-up attic. He has a dormer facing west, and was planning to mount antennas there. Easy to get to them from attic. Can he mount all the antennas on one plate or should he space them out?
  - regional HF (20m) antenna and dual-band 2m/70cm antenna.
- WA3VEE, Ron:
  - Personally doesn’t like to have antenna on the house, since it draws lightning.
  - How much land?
    - Simon: L-shaped, 1/3 acre, but no trees that are actually his.
  - 40M would be a good horizontal wire for regional NVIS
  - grounding is imperative for lightning protection of the house.
  - those antennas, in size, are very different.
  - wires are easier for HF
- W3GMS, Joe:
  - the Hustler 5-BTV for 80-10M is a good option
  - he has radio and tuner for Simon
- W3MFB, Mike:
  - Hustler in the yard would be a good option
  - pin down the feed line and radials with lawn stakes
  - neighbors trees: any limbs over your property could be used to hold up an end fed antenna
  - get the antenna as high as you can get it
- WA3KFT, John:
  - He has 5 antennas at the top of a tower, like a candlabra.
  - an edger is good for grooving the lawn for wires
- WA3VEE, Ron:
  - sent link to the Hustler 5-BTV
  - the digital modes are FT8 and PSK31
- W3KZG, Scott:
  - Has an NMO lip-mount with dual band antenna clamped to the rain gutter of the shop.
- KC3NZT, Harvey:
  - using a copper pipe j-pole inside in the attic of the garage.
    - should work just fine.
  - an HF antenna in the attic would work fine too
- WA3VEE, Ron:
  - for new hams and those in HOAs, attic antennas can be effective
- W8CRW, CR:
  - Why’s the 5-BTV so highly recommended, compared to other variations?
  - WA3VEE, Ron:
    - the 5 walks the line of versatility and size
    - they’re different sizes
- W3GMS, Joe:
  - a 4-BTV is 4-bands, 5- is 5-band, etc.
- KA3GLI, David:
  - on the 5-BTV, what auto-tuner is recommended?
  - W3GMS, Joe:
    - LDG RC-1 auto-tuner helps match as you get away from the vertical’s narrow, high-Q, resonant spot.
- KD3EE, John:
  - remember you can build these HF antennas with some wire and toroids.
KD3BPI, Simon:
- How does height affect performance of a vertical: ground vs roof?
- W3GMS, Joe:
  - wire radials on the ground are easy. detuned by the earth.
  - lots of short radials are best
  - elevated radials will perform better, but will require tuning of radials.
  - random lengths are fine on the ground
- KC3WRY, Matt:
  - a ground-mounted antenna is easier to tune, instead of up in the air.
  - ground-mounted can always later be moved.
- WA3KFT, John:
  - worked at an AM radio station.
  - when they moved, they rebuilt all the radials.
    - 60 short and 60 long radials
- W3GMS, Joe:
  - 8 radials with the 5-BTV at the beach was fine
  - gains aren’t as impressive after the first radials

Flagpole Mast Down

Thu, 06 Nov 2025 00:00:00 +0000

The flagpole mast broke in the wind about 9:05pm EST or so. I captured the destruction on the Wyze camera that watches it. It snapped right above the point it’s tied to the garage. Fortunately, it fell in an OK direction, so it didn’t damage anything around it.

I could try to put it back up with some spare pieces and guy it next time, or I could try the military surplus mast I picked up at a Ham Fest this past summer.

I’ll be contacting the 985 repeater digitally through Allstar for now.

broken flagpole laying in the yard

Higher Home Antenna

Sun, 10 Aug 2025 00:00:00 +0000

I watched Youtube and saw a better way to throw the line by cradling the weight on the line and swinging the weight between my legs. It’s much more confident, powerful, and accurate. I threw my home antenna higher in the same tree. It’s so high that I needed to add more throw line now.

!–more–>

RX with Disconnected Antennas

Thu, 17 Jul 2025 00:00:00 +0000

K3IR/145.230MHz for the Morning Grind was clear, but low power (S3-S5) on the Quansheng and TH-9800 base. It turns out that both antennas were disconnected at the window for overnight storms.

High SWR 80m EFHW

Wed, 11 Jun 2025 00:00:00 +0000

I was seeing high SWR on the 80M EFHW: over 3:1+. I found counterpoise was chewed and broken, so I twisted it back together, but I saw no change. I disconnected the counterpoise completely, and that made no difference: still 3:1. I finally unscrewed and re-screwed the rusty alligator clamp and reattached it. That fixed it!

Previously, it seemed I’d sometimes see high SWR for a a moment, then it would recover. It seemed like giving it a little power would “clean up” something.

64:1 Unun for 80M EFHW

Tue, 13 May 2025 00:00:00 +0000

Today I experimented with building a 64:1 unun for an 80-meter EFHW.

My initial attempt involved 3 primary / 24 secondary windings, but I quickly found that this took up too much space on the small toroid I was using.

After some adjustments, I settled on a 2 primary / 16 secondary windings, adding a 100pF capacitor. This configuration was inspired by resources like KM1NDY’s DIY linked EFHW 64:1 antenna guide.

I’m now successfully running my home EFHW antenna on 40 meters without needing a tuner. On 17 meters, the SWR is a bit high, so I engage the tuner for that band.

This setup reminds me a lot of my previous 71-foot random wire antenna with a 9:1 balun. I’m noticing a significant increase in the number of signals I’m receiving, which suggests this new EFHW might be a considerable improvement over my old 107-foot EFRW.

Launched 80M EFHW Antenna

Mon, 12 May 2025 00:00:00 +0000

I launched my 80M EFHW at home, replacing my previous random wire setup. I’ve trimmed it up and folded it back, but it still needs the tuner to touch it up. I’m seeing the expected harmonics near each ham band, which is a good sign. My next step is to build a new 49:1 transformer for it.

POTA US-1418: 2025-03-29

Sat, 29 Mar 2025 00:00:00 +0000

I setup at US-1418 for an activation. I tried to setup the 40m EFHW in a nearly vertical configuration, but my throw wasn’t high enough, so I went for a vertical 25-foot Rybakov instead. I used my 4:1 balun.

I got my activation working 10M and 15M FT8.

picnic table

antenna transformer

woods

Fixing the De-tuned Slim Jim

Tue, 25 Mar 2025 00:00:00 +0000

The slim jim I put up for APRS was hanging right next to the feed line of the higher quarter-wave antenna I use for local analog traffic. The feed line was de-tuning the slim jim, so reception of APRS traffic was almost non-existent. I could swap the antennas and the higher one worked much better, and the lower slim jim was greatly degraded for other FM traffic. Usually the BTech is on the lower slim jim, and the Quansheng is scanning on the higher quarter-wave.

To correct the problem, I pulled the 2 antennas up on separate ropes and separated them by a couple feet. The quarter-wave is still mounted higher than the slim jim.

Breakfast and POTA

Fri, 21 Mar 2025 00:00:00 +0000

I went to the 985 breakfast and chatted lots of Vic and Jerry.

After breakfast, I hit the parks for some POTA. I started at Middle Creek where I tested my EFHW vs the Tactical Delta Loop.

Next, I setup at State Game Land 156 down the road with the telescoping antenna for a CB walkie talkie.

Middle Creek

EFHW

Setup at Middle Creek

Tactical Delta Loop

TDL Hub

Setup along the road

Fixing the 4:1 Unun

Tue, 04 Mar 2025 00:00:00 +0000

I had followed the these nice directions to build my 4:1 unun to use with a Rybakov and Tactical Delta Loop, but I made a mistake:

the wires that come from the shield continue in opposite directions around the toroid
on my bad build, they originally both went the same way side by side.
the diagram is clear, if you look closely, but the picture is even clearer.

I tested the 4:1 with the tactical delta loop. It consists of:

the 4:1 unun.
2 17-ft telescoping whips up diagonally 90 degrees from each other.
25-ft wire connecting the ends of the whips with alligator clips.
3d-printed plastic mount to hold it all at the bottom.
screwdriver stuck through the mount into the ground to hold it up.
alligator clips to connect the unun to each side of the loop.
ground spike (screwdriver) wired to the ground side of the loop/unun.
tuner is required to work 40M-6M. 80M and 160M didn’t want to tune.

4:1 unun corrected

Newly-Tuned Slim Jim

Tue, 25 Feb 2025 00:00:00 +0000

I launched the newly-tuned slim-jim antenna. With it hanging from the fan, it looked tuned. Hanging right next to the siding outside the window, it looked long.

I launched it into the tree to hang right below the quarter-wave. Hanging in the tree, it looks well-tuned. I compared both antennas simultaneously with the 2 Quanshengs, and the lower slim jim measures 10-20dBm lower than the higher quarter-wave when receiving.

Reconditioned HF Antenna

Mon, 24 Feb 2025 00:00:00 +0000

I reconditioned my HF antenna. The SWR was being wonky and variable on the 107ft EFRW: jumping to 3:1 with tuner. I cleaned up the wire ends and alligator clips with sandpaper, reconnected them, and repositioned the counterpoise. Now I’m seeing 1.5:1 SWR with the tuner.

EFRW Clips

Home Wire Down

Fri, 21 Feb 2025 00:00:00 +0000

The rope came undone at far end of my EFRW. I had to fish it back down with a wire hook stuck in a fishing pole.

The SWR was a bit high, and I found broken wires in 9:1 balun, so I stripped the wires and reassembled it.

With the antenna working again, I contacted New Caledonia on 10M FT8 with 8W.

Rebuild Quarter Wave

Tue, 18 Feb 2025 00:00:00 +0000

The quarter-wave ground plane antenna in the tree disconnected in the wind, so I brought it back down and rebuilt it stronger with radials passing through the holes and woven together. I used randomly shorter radials, but 8 of them this time. I watched the SWR drop with the nanoVNA as I added radials. I resoldered the driven element into the socket and trimmed it to tune it again.

SPARC Elmer Night: 2025-02-18

Tue, 18 Feb 2025 00:00:00 +0000

I took along the old slim jim antenna I bought at my first ham fest. I understand now better how to tune it: I need to make it a little longer, not just slide the feed point up and down the batch.

The antenna was a little short by measurement with the NanoVNA. I hung it from a fan in the middle of the room to measure it without interference. I lengthened it at the far bend by soldering some extra house wire in the bend.

Now it looks perfect for 2m and 70cm.

New Antenna DX

Tue, 11 Feb 2025 00:00:00 +0000

The new 107-ft (32.6m) EFRW in the backyard is doing OK, and I’m getting pretty lucky with low power on 10M FT8.

Japan (10500 km): 5W, 2025-02-10 2245 UTC
Norfolk Island (14000 km): 2W, 2025-02-11 2238 UTC

107ft EFRW

SWR with the Long Wire

Tue, 31 Dec 2024 00:00:00 +0000

I was using the 71-foot (21.64m) EFRW antenna at home, and I noticed SWR was surprisingly low as measured by the X6100 with the tuner disabled. I suspected loss on the feed line, but I also found this video of another person not using a tuner with the same antenna.

I disconnected my feed line at different places to find SWR jumps way high, so the measurement is working:

inside window
outside window
at the antenna

Does a very long wire have low SWR for everything? Is the 9:1 giving low SWR? The antenna’s working fine, and FT8 shows far-flung signals like always. Disconnecting antenna wire raised SWR above 1.5:1, but not much. Even with wires disconnected from the balun, it’s receiving a very few FT8 signals on 10m, and I can still transmit, but it’s folding back power with SWR just below 2. The tuner is definitely needed for 6m.

Antenna Maintenance

Sun, 29 Dec 2024 00:00:00 +0000

The 1/4-wave ground plane antenna in the tree dropped its feedline, so I brought it down to reattach it and resolder the radials.

I also walked down the yagi on the pole to straighten some elements, since it was a nice day. The yagi was spinning around in the wind, so I also changed the way it’s mounted to clamp it more securely.

I also added some reigns to the mast, so I can (try to) spin it from inside the window. It works well some times but not others. The pole can freeze to the ground.

NVIS

Sat, 21 Dec 2024 00:00:00 +0000

I watched a video about NVIS NVIS achieves 75-90 degree take-off, very vertical, and about a 400-mile range. It can get you over obstacles. It’s most effective on 40m and 80m.

To build it, mount a dipole 1/8 wavelength above ground, horizontal. Add a reflector almost on the ground, 5% longer, to keep the ground from absorbing the signal.

21 Tech Net: 2024-12-08

Sun, 08 Dec 2024 00:00:00 +0000

My Week in Radio

Contesting

I finished the FT Challenge. There was no special exchange this year. We could use other defined subbands in addition to the regular frequencies to alleviate crowding. We could work anyone, even if they’re not participating explicitly.

I operated QRP, so it was nice to find the quieter subbands and more FT4 activity. You earned multipliers for each 3000km, so I don’t really know on my score yet.

I found wsjtx-improved on the Debian Linux repository, so used that. I saw the color improvements, the better location labels with states, and it had filters.

AllStar

I learning some obvious things about AllStar: it can’t hear my DTMF if it’s currently transmitting, since it’s simplex, so it’s hard to control on a busy net.

Yagi in the Wind

Finally, I watched my home-built yagi flapping around on that windy day. I guess I can stop worrying about it, since it held up fine.

Antenna Maintenance

Fri, 22 Nov 2024 00:00:00 +0000

The home-brew yagi blows around in the wind a bit, so I brought it down this morning as it started to snow, so I could straighten and tighten the elements. I realigned it for the 985 repeater, and checked it to be giving -96dBm.

I also resoldered some radials on the 1/4-wave ground plane antenna that go knocked loose in the tree.

flag pole mast

straightened yagi

Yagi Pole Upgrade

Mon, 21 Oct 2024 00:00:00 +0000

I added some sections to the flag pole to reach 37 feet, and I increased elements on the home-made yagi from 2 elements to 4 elements. Upon adding elements, I needed to stretch the driven element a couple millimeters longer to tune it. In testing, I’m seeing about -100 RSSI listening to W3GMS on a Quansheng. It was about -105 RSSI when mounted lower and only 2 elements.

Yagi upgrade

2-Element Yagi on the Flag Pole

Wed, 16 Oct 2024 00:00:00 +0000

Tilt-up Flag Pole

I figured out to do a tilt-up flag pole against the house reaching 25 feet into the air. It sits on a stake in the garden, and is secured to the house with paracord in an eyelet and hook screwed into the side of the roof.

2-Element Yagi

I built a new 2-element yagi using an online calculator It tuned OK with the banana-clip adapter directly connected to the driven element. I first tuned the dipole, and then added the reflector element. As predicted, it shifted the tuning slightly, so I trimmed the driven element to retune. The nice thing is that the spacings and sizes of the original elements don’t change as you add more director elements, so I calculated it with 2 or 3 directors, but put none in for the first iteration. I can add more elements later.

I gave it a try to reach 985 with the TYT TH-9800 running 50W. It was scratchy, but copy-able. I have more flag pole sections ordered to make it a little higher.

PVC attachment

banana-clip connection

flag pole

yagi on pole

secured to house

cord to ground spike

Amazon Prime Day

Wed, 17 Jul 2024 00:00:00 +0000

Prime Day popped up a few good-enough sales, so I bought a few things.

50w dummy load
TIDradio TD-H8 - HT, 10W, bluetooth, clear case, etc
TYT TH-UV8000D - HT, 10W, crossband repeater
- This should allow me to crossband relay to a repeater via the outside antenna and wander the house with a smaller HT
BNC adapters for HTs.
- Everything goes to BNC for easy swapping to external antennas.
4 HSY Telescoping VHF/UHF antennas with BNC connectors for HTs
TinySA
Sony headphones, wired, as backup for the ones I use now for POTA
2 Pi Zero W kits with cases, connectors, and all that
375ft of micro cord for throwing antennas into trees

Broken EFRW

Sat, 22 Jun 2024 00:00:00 +0000

My 12.5m EFRW at home broke again, so I needed to restring it. The wire breaks at the tie point up in the tree. The kids and I failed to launch it again over the tree with slingshot out the window. I had also tried some small 3d-printed s-biner clips, but they’d release as soon as I launched with the slingshot I got the wire running flat through the other tree instead of up and over.

That didn’t last too long. The wire broke again at the tie point, so I launched it from the street again with the throw line and sockets. I kept it a little looser and switched to a bungee cord to keep it tensioned with some play.

Tape Measure Yagi

Sun, 16 Jun 2024 00:00:00 +0000

There are easy instructions to build your own yagi on Instructables. I had just picked up some hose clamps and had the other necessary pieces: a broken tape measure and some 3/4-inch schedule 40 PVC and connectors; so I was ready to build.

The wiring on mine is held in place by the clamps and banana clip adapter. I always like those for prototyping. As directed, I tuned the antenna by moving radiators in and out and measuring with the NanoVNA.

The antenna is noticeably directional, so I can use it to find directions of signals. The S-meter and dB signal strength numbers on AUBS firmware make it easy to evaluate strength and direction.

I transmitted with it to the K3IR repeater as a test during a net.

Tuning the GRA-1900

Sun, 16 Jun 2024 00:00:00 +0000

Initial Tuning

The one-page document that comes with the GRA-1900T antenna detailing the jumper positions on the coil and the lengths at which to set the whip for each band didn’t seem to match up all that well, which led to some frustration out in the field.

I decided to use my NanoVNA to reconstruct my own instructions for using the antenna. I extended the whip fully and recorded the resonant frequency for each jumper position of the coil. Knowing those frequencies, I can set the jumper and shorten the whip until the SWR sweep on my x6100 is happy. The SWR graph on the x6100 can be misleading sometimes, because it often shows a birdie dip or 2 in the graph, but now I’ll always know that I’m to shorten the whip to get where I need to be.

I’ll eventually apply labels to the coil with these frequencies.

US-1425 Susquehannock State Park

I took the GRA-1900T out to Susquehannock State Park for a field test. My plan to tune the antenna worked well. I set the jumper for the frequency below my intended operating frequency and shortened up the whip until the x6100 showed a good SWR curve. Easy!

Oops, Broken Fishing Pole Mast

Since I hadn’t used the fishing pole at the park, I forget I had it and left it behind when I packed up. 2 days later, I returned to retrieve it. Some kids had found it, had trouble collapsing it, dug in the dirt with it, and broke a section.

I was able to put it back together with the remaining sections, and I 3d-printed a new fork/loop to make it useful for supporting wire.

Tuning the Counterpoise

Fri, 14 Jun 2024 00:00:00 +0000

My antenna wires at the house were getting moved around a bit with some projects. I found my SWR was a bit high on a certain HF band, and I found moving or coiling the counterpoise (~5.2M) to shorten it greatly reduced SWR. I have to remember to watch performance and adjust the counterpoise as part of my setup and operating.

Antenna on the Car

Fri, 07 Jun 2024 22:45:48 -0400

I removed the magnet from the inexpensive mag-mount antenna that I had stuck to a baking sheet in the back of the BMW i3 (which is all plastic). The bike rack is always on the car, so I cobbled together some scrap metal parts and clamped the antenna onto the rack. It’s got a screw knob, so I can loosen and reorient it when I flip the bike rack.

It works great now with the antenna outside the car and attached to the metal of the rack.

985 Workbench Net - 2024-05-20

Tue, 21 May 2024 08:56:22 -0400

My Week in radio

The Vertical EFHW

I Tested my 20m EFHW wire and unun on 2 different POTA outings In an inverted v with a counterpoise, it worked pretty well, but could be shortened. As a vertical, the SWR was higher, and the counterpoise made it worse. I compared the vertical EFHW to the trusty old EFRW in a mostly vertical configuration. That one had exhibited a terrible SWR as well with or without counterpoise. Maybe I needed more radials instead of a counterpoise? I have 2 ARRL antenna books, basic and the big one, so I could read, I suppose. During these experiments, my computer experienced some common-mode interference too.

Custom Antenna Winder

I 3D-printed a nice customized winder with the transformer attached. I modified the code to be parameterized to any size I want.

More VHF

I’ve been discovering I can hear some further repeaters using the spectrum analyzer feature on my Quansheng, so I’ve been adding more repeaters to the scan.

Thoughts on My Vertical Antenna Problem

You can tune and end-fed at one angle, and it can have a different swr at another angle.
They’re sensitive to objects in their near field. Is the unun near ground or branches? The same goes for the other end of the antenna. Try changing the orientation.
The ends are high-voltage, so they’re sensitive to capacitance. The middle is high-current, low-voltage.
Vertical antenna will have very different conditions at each end. inverted-V or horizontal will have more similar conditions at each end.
RF comes from the current in the middle.
- Vertical is an inexact science.
- The tree effects it.
- 50ft of coax helps provide RF ground, and less can be a problem.
Watch height of unun.
The Smith chart on the NanoVNA can help evaluate what’s happening.
- Crossover point on the chart can show the tuning and the swr
- Is it environmental or the wire?
Counterpoise placement can be sensitive.
Add radials for vertical.

Interesting Bits from Other People

Tim, W3QP, did the W2 SOTA campout: 6 summits and 32 contacts, mostly VHF.
Chuck, NA3CW, talked about accomplishing an 75M net using online WebSDRs to hear, because propagation was so bad.
Rob, K3VIL, is having fun with his QRP IC-705.

POTA Antenna Test 3

Mon, 20 May 2024 03:19:48 -0400

I compared the 20m EFHW with the 12.5m EFRW at Sam Lewis (US-1418). I threw really high and made both antennas nearly vertical into high trees, not inverted-v.

EFHW could hear pretty well, and the SWR sweep showed again that I could shorten it, so I did lower it and take off a few cm.

The EFHW didn’t seem to like its counterpoise. With the counterpoise, it was giving me an SWR of 2-2.5:1 on 40m when I transmitted. If I removed the counterpoise or kept it coiled up, the SWR was lower. I still made most my contacts on 40m.

I think the radio may have again been interfering with the mouse when transmitting. I already had chokes on both ends of the feed line, but adding the counterpoise helped that common mode interference. It was a rough day.

The EFRW would not tune well at all on 40m with or without its single counterpoise. That surprised me greatly, because I had tested that same unun with my existing EFRW antenna out the front window at home.

I wonder if it had something to do with each antenna being mostly vertical. I wonder if they needed more radials instead of a single counterpoise. K4OGO (Walt of Coastal Waves and Wires) always adds so many radials to his verticals.

This had me questioning everything. I thought I was doing something really good by getting the wires high and vertical. When I brought the radio home and connected to the same old EFRW, it was again performing normally.

I also learned that the POTA website cuts off your activation and starts a new one at 00:00UTC, 8pm, so I ended up with 2 QSOs counting toward a second (incomplete) activation at the park.

EFHW into tall tree

EFHW winder

EFRW winder

985 Workbench Net - 2024-05-13

Tue, 14 May 2024 18:24:59 -0400

My Week in Radio

I purchased some power cables that split out the 12V line out of USB-C, so I can power my radio from a USB-C power brick/jump-starter battery.
Marie and I relaunched my EFRW even higher into the the tree in the front yard. I used the slingshot out the second-story window, while Marie watched that the street and sidewalk were clear.
I did the RTTY test and FT4 sprint last Thursday.
I saw some better propagation on FT8 before the weekend’s solar storm: Ukraine, Northern Ireland, and Greenland at the arctic circle.
While the bands were dead over the weekend, I built a couple new, lighter antennas for POTA. I cut and tuned some 20m-long EFHW wires and tuned them with NanoVNA. I used recycled plastic gum boxes as enclosures and winders for the un-uns and wires. I also 3d-printed a winder that holds the transformer and heavier speaker wire. I’ll test the antennas when bands are obviously better. I’ve not really used an EFHW much, so I’m curious to see how it performs compared to EFRW.
I saw some recovery today in the band today: Panama, Canary Islands, and the Cayman Islands.
Ron, WA3VEE, sent photos from the Antique Radio Meet in Kutztown.

My Question for the Night

What are the effects of solar cycle and solar activity on propagation? We’re in a high point of the solar cycle, so 10m is good, but too much and it blacks out propagation?

Discussion

Vic, KC3TYX, made a VARA-C contact.
Jim, KC3RFG, found an OCF dipole to be quieter than end-fed.
Jim, AF3Z, has trouble with his Ten-Tec radio sometimes not transmitting.
Jeff, W3JAM, wondered if anyone was making 6m contacts over solar storm.
Mike, W3MFB, noted that 17m sometimes is a pipeline right into Florida in afternoon/evening.
Tim, W3QP, is headed on SOTA campout.
Jack, K3YVQ, Is it OK to use GMRS on a radio that does ham freqs and more?
- Mike, W3MFB: technically, the radio should be locked to gmrs frequencies.
- on the air, no one would know, though.
- Ron, WA3VEE: FCC approves radios for particular services.
- GMRS radios are “type-acceptance”, and the right power limits.
- Some other radios might be hard to limit to the right power.
John, KC3WWC: What’s the solar storm do to propagation? Some activity is OK, but too much is bad?
- Chuck, NA3CW:
  - RF is produced by accelerating (“wiggling”) electrons.
  - Ionosphere doesn’t “bounce” signals, but instead “receives” and “retransmits”.
  - We have loose electrons in the upper atmosphere, good for retransmit.
  - Solar storm ionizes the atmosphere at different levels with varying intensity.
  - Our RF hits ions in lower part of the atmosphere and gets slowed, absorbed (D layer).
  - LF is affected the most, since it moves the electrons further.
  - Solar minimum offers less ionization at any level.
  - D layer, E Layer, F1 layer, F2 layer.
  - Better shortwave propagation at night.
  - Lots more is understood now about the ionosphere.
  - Frequencies are coordinated in SW to adapt to seasonal changes.
  - Electrons free in thicker air recombine more easily, so don’t pass RF.
  - Winter: great distances, because air is thinner.
- Tim, W3QP: noise also comes up during storm and masks signal.
- This video from Coastal Waves and Wires explains the effect a bit.

New Wires

Sat, 11 May 2024 15:41:09 -0400

The bands were dead with the terrible geomagnetic storm this weekend, so HF is very limited. I was only able to contact Lititz from Mountville.

With the downtime, I built some new EFHW antennas. I tied some wires to trees, stretched them out, and tuned each of the 2 20m EFHW antennas with the NanoVNA: one speaker wire, and the other lightweight silicone wire. I built new ununs and mounted them in plastic gum cases and a 3D-printed winder.

I also cut a lightweight EFRW, 12.5m, from the silicone wire and gave it a gum case as a winder.

I’ll test the new antennas soon when the bands are better.

EFHW Gum Case

EFHW Winder

EFRW Gum Case in Use

Backyard Alternate Antenna

Sun, 05 May 2024 00:00:00 +0000

I cleaned up the backyard a bit, and ran a new 12.5m (41ft) random wire up the hill behind the house.

My first tests the next day on 30m at 1W got me some contacts. By 4:40pm EDT, the bands were all in “poor” condition, so it got tough to test.

The next morning, I watched the 40m band close. It was ablaze at 8am, but getting pretty quiet by 10:30am EDT.

I compared the old antenna out the front with the new antenna out the back using FT8 and PSKReporter.

The back antenna saw fewer decodes on 15m on average. It mostly lacked any stations from Europe. Looking at the antenna’s physical attributes, it starts on first floor (lower than the old antenna) in backyard, but it slopes up more vertically. The middle of the antenna, on average, is blocked by the hill to the East.

The old antenna out the front saw more decodes overall, including Europe. It starts at second floor window and only slightly angles up. The whole antenna is higher and clears the hill, even though Europe may still be mostly all the end of the antenna. It performs better.

I had fun physically launching the new antenna, but I’ll need to do some more work to get more of it higher in the air to be useful.

985 Workbench - 2024-04-29

Mon, 29 Apr 2024 00:00:00 +0000

My Week in Ham Radio

Built and deployed a 1/4 wave ground plane with radials
- wire soldered to an UHF chassis plug
- fed from the bottom
- hung in a tree by cord
York Hamfest and 2 parks out that way
- Codorus
- Sam Lewis
- EFRW
- Mostly ft8
- 40m hot at 5:30pm
- 2 phone contacts in Canadian parks for park-to-park QSO
- Took some time to experiment a little
- Fishing pole mast with 3D-printed fork on the end to catch the wire
- Stop pulling on coax…loosened ends
SPDX RTTY contest (Poland)
- 2 contacts
- ended at noon UTC on sunday, so ran out of time
AubsUK firmware for Quansheng
- 10 scanlists
- automatic scan on power-up, feature request
Picked up a new podcast: Ham Radio Workbench
Simplex Net: heard 16 of the 38 people

My Questions

with nicer weather and time to experiment with antennas, how would you recommend iterating and experimenting? I have:
- the QRP transceiver
- digital modes & pskreporter
- nanovna
- some modeling software I could learn
- the latest ARRL Antenna Book

Discussion

Dipoles, sloped or flat?
- Flat leaves nulls toward the ends
- Sloped fills it in to be a bit more omnidirectional
- An antenna close to the ground is going to be NVIS
- Vertical is omnidirectional
Ron’s seeing infinite SWR on the “screwdriver” antenna.
- Others have had problems as well.
Mike wonders about viability of using 6m FM in his area
My Question: How should I evaluate and structure my experiments with antennas?
- Conditions change constantly
- Learn to read solar data
- Take notes on conditions and try to test in similar conditions
- Vic’s experiments:
  - endfeds
  - hamsticks
  - radials
  - aluminum screen or faraday cloth for ground plane
- WSPRnet and pskreporter help gauge how you’re getting out
- See what you can hear
- Qualify callsign for different tests, so I can tell them apart in pskreporter: kc3wwc/a, kc3wwc/b, etc
Ken wonders about TNC for packet radio on HF/VHF
- Glenn, N3MEL would be the person to contact
We heard lots of interference and doubling in the beginning of the net
- This was likely another manifestation of intermod
- Tropospheric ducting happens more in morning in the summer

Quarter-Wave Ground Plane Antenna

Wed, 24 Apr 2024 14:06:38 -0400

I followed calculations and instructions to build a quarter-wave ground plane antenna from some wire and a UHF connector that I picked up at the last Ham Fest in Harrisburg. I cut everything a little long and soldered it together. I trimmed the radials to about 54-inches and folded and rolled the radiator wire to a length that is resonant at 147MHz. I measured with the NanoVNA. Once it was at the right frequency, I found that bending the radials up and down could adjust the SWR at its lowest point on the graph. Keeping the radials slightly flatter had a lower SWR than the 45 degrees suggested in the original design.

This ground plane antenna feeds from the bottom, which is physically more sound than the vertical dipole I had up previously. I tested it last night when I strung it up, and it reaches Harrisburg and Parkesburg with no problem.

2m Ground Plane Antenna

Ridley Creek POTA

Sat, 13 Apr 2024 00:00:00 +0000

We had some time in West Chester to visit Ben and see the new Mini Countryman, so I stopped by Ridley Creek State Park to activate. I had lots of tangles trying to toss my 21.56m EFRW into a tree – it took 30 minutes just to get started, but I had the wire at least 25 feet into the air. I operated FT8 and FT4 on 10m from a pavilion. I hit lots of Western US, some Europe, Brazil, and even New Zealand!

Eclipse 2024

Mon, 08 Apr 2024 00:00:00 +0000

Matt and I ran to Erie, PA to watch the eclipse, and activated US-1402, Presque Isle State Park before eclipse. 10m was a bit slow, but I got there on FT8. I ran my 71-foot (21.65m) EFRW sloped up into a nearby tree from our station on a picnic table.

I got some audible screaming on the speaker in addition to the normal clicking when I hit the tuner. I usually have a choke near the radio, and that was missing.

It was cloudy and even some rain in the morning, but it cleared and we saw some blue sky before the eclipse started around 2pm.

Totality was at 3:16pm EDT. I have a video in 360 degrees.

Totality

FM Bandstop Filter

Wed, 03 Apr 2024 00:00:00 +0000

I posted to Facebook and got lots of discussion about the FM bandstop filter.

When I started adding better external antennas, I could reach further (tx and rx**, but I also found that some VHF frequencies got much worse. It turned out I was overloading the receiver with the strong FM broadcasts in my area and increased sensitivity of the better antenna. I found a bandstop filter helped bring back those signals I was losing.

VHF Reception

Tue, 19 Mar 2024 00:00:00 +0000

Reception Problems

During 985 net on Monday night, which is VHF on my UV-K5 running egzumer 0.22.0, I’d get periodic static in reception. It got bad enough to completely cut-out. I was using my simple wire dipole hanging in the tree outside.

K3IR had been frustratingly quiet as well, so I checked the antenna with the NanoVNA as it hung outside. There were no fluctuations in SWR, so it’s not connections or proximity.

I tried the Explorer QRZ-1 HT, and it sounded great on the same antenna on the same net. Is my UV-K5 broken?

To test a bit further, I ordered a new UV-K6 to compare. I also downgraded to egzumer 0.21.0 for further testing.

The next day, Tuesday morning, K3IR was sounding better, but I was getting the same periodic noises. The outside antenna doesn’t completely cut out, but shows terrible doubling/overload as if from FM station.

Inside, the magmount antenna on the 3d printer is better. Is the dipole outside too sensitive and bringing in more signal than the frontend of the UV-K5 can handle?

New 21.56m EFRW

Thu, 29 Feb 2024 00:00:00 +0000

I assembled a new 71-ft (21.56m) EFRW and strung it up at Emily’s. It’s 5-6ft off the ground. I give it a 17-ft (5.2m) counterpoise and a 9:1 unun as usual. 2:30pm EST, 1W into it gets me midwest to a little bit of Europe on 10m. I’m not making many contacts, so I bumped up to 5W.

The antenna tunes on 40m too just fine. I’m getting a few more contacts there.

As a new strategy, I’m aiming for ALC around 1.0, instead of just below any movement. This allows me to not touch the power slider in WSJT-X quite so much.

Ladder Line J-Pole

Wed, 17 Jan 2024 00:00:00 +0000

I bought a project J-Pole made of 450-ohm ladder line at the Hamfest for a couple dollars. I rebuilt the connections, firmed up broken parts with some wood splints and tape, and tuned it with the NanoVNA.

It seems to be working pretty nicely for 2m and 70cm. I’m pulling in stronger signals, and still able to transmit.

Tuning a Dipole by Coiling

Mon, 27 Nov 2023 00:00:00 +0000

I have a dipole that’s 20m long (10m each side) strung through the house right to the banana plug adapter to the radio and no coax. I’ve coiled the wires together at the feed point to shorten and tune. I can run 40m with tuner turned off. I’m hitting Europe, Central America, Canada, and the midwest US.

I figure, since the wires are insulated and kept parallel to each other, the coil is serving as feed line and not part of the antenna.

Antennas

Tue, 07 Nov 2023 00:00:00 +0000

Antenna of the day: 12.5m random wire w/ 9:1 unun strung from high in loft to the outside laundry line. It tunes for 10m, 12m, 15m, and 20m nicely, but not for 40m. I switched to 5m dipole twist for 40m.