Inspired by a paper from HB9BCB I built my own version of a small and lightweight coupler for an EFHW dipole. It helps reducing the weight of my radio equipment for long hikes to alpine summits (see here).
Sometimes a summit offers little space to deploy an antenna. Either because there isn’t much room or because there are many people at the top – or both.
Then an antenna with a small footprint is required.
December 18, 2020 11:40 – 13:50 UTC
My first activation of Hohloh (after I had to cancel it in September due to a blocked road).
Wx: Sunny, approx. 6°C, no clouds
Walking time: 20 min. up, 20 min. down
Ascent/ descent: approx. 100 vertical metres
Excellent condx on all bands. SFI = 82, k = 1.
14 CW QSOs on 60m, 1 x S2S
50 CW QSOs on 40m, 1 x S2S
16 CW QSOs on 30m, 1 x NA
24 CW QSOs on 20m, 1 x S2S, 3 x NA, 1 x OC
– 104 QSOs in 130 minutes – an all time record!
– First SOTA-QSO with ZL
– Re-deisgned EFHW-transformer with the smaller T82-43 toroid works excellent.
– An IK2-chaser calling non-stop without ever being able to copy my signal
Some time ago I had an S2S-QSO with N1ZF. In the following e-mail contact we exchanged information and photos about the antennas used for this QSO. This is when I became aware of the „Random Wire Antenna“ Paul had successfully used.
A delta loop antenna – especially for the 40 metre band – is not exactly suitable for SOTA. It is huge and requires a lot of space. Furthermore the set up is time-consuming.
Nevertheless I’d like to show this design here because:
- During sunspot minimum 40 m still offers the opportunity to work a lot of DX.
- The delta loop provides the required take off angle to work the DX.
- Sometimes space (and time) don’t matter.
- It’s fun building it 😉
A possible application could be intercontinental S2S events.
Here is the Link to the 20 metre version of the delta loop.
During our DX-pedition (Link) to the Principality of Liechtenstein in Sept. 2013. DL4AAE worked hundreds of JA’s on 20 metres with this antenna and 100 W output power.
Recently I came across an article from Andrew, VK1AD, in which he describes a QRP L- tuner for 3.5 MHz to 52 MHz. It can be found here.
Andrew’s article is based on an essay by Peter, VK3YE, published in VK’s Amateur Radio magazine, Edition 5, May 2017.
I really wanted to try this easy to build L- tuner, because I thought it might perform even better than my EFHW- transformers (UnUns) and the EFHW- dipole I’m currently using for my SOTA activations.