Efrw on John Flinchbaugh KD3EE

71-ft EFRW

Mon, 07 Jul 2025 00:00:00 +0000

I went back to my favorite 71-ft EFRW for the home antenna wire. The EFHW was requiring tuning, so I figured it may not be worth having.

POTA US-4567: Marietta Riverfront Park

Fri, 04 Apr 2025 00:00:00 +0000

Rain was predicted later in the weekend, so I headed out to Marietta Riverfront Park (US-4567) for a quick activation to beat the rain. My initial plan was to rebuild my EFHW antenna, but I cut the new wire six inches too short, and I didn’t have enough wire on the spool to start again.

I opted for my 12.5m EFRW instead. It was 7 PM, so I focused my efforts on the 40m. I successfully got about 18 contacts before I packed up for the evening.

Marietta Riverfront

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

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.

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.

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

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.

Power Supply Noise

Tue, 14 Nov 2023 00:00:00 +0000

Running the 41-foot (12.5m) random wire, it works great for 10m and 20m. It tunes really quickly. The power supply gives lots of buzzing and noise on these bands. ATT tames the power supply noise pretty well.