Category: DX Commander

Beaming 240 degrees from UK to VK

This is my biggest DX Commander antenna and needs careful planning and execution to make sure this goes up first time without a hitch. But the rewards are big! Enjoy the fun – and the mistakes.

This build uses this cut chart:

80m – 21.23m (For 3.8m and above, use 20.75m)
60m – 13.02m
40m – 9.77m (USA / Region 2 – use 9.7m)
30m – 6.88m
20m – 4.87m
17m – 3.86m

NOTE: 15m, 12m and 10m are not guaranteed – although your ATU will easily tune them – same with 6m band.

00:00 Intro
21:50 Crash
50:34 Result

Although I happened to win my chosen IOTA Contest Category (Woo-Hoo!), the real purpose of this video is to thank those "behind-the-scenes" folks who collate the contest logs and then manage to score the whole event inside 6-weeks. Reading between the lines, there’s probably a ton of errors that creep into these logs with people claiming the wrong category and mixing-and-matching corrupt ADIF files etc. By the sound of it, many of these are probably fixed "by-hand" until eventually, when all the logs can be machine readable, a big process somewhere is finally given the task of collating eveything and all the different categories; multi ops, single ops, 12 hours, 24 hours, assisted, non-assisted, island stations, world-stations – and more into order. So house-points and gold-stars all around. Thank you to the invisible team behind the scenes. 73, Callum M0MCX (Club Call M0XXT).

This time, I went to the Telford Rally. I ran a TS-590SG and a DX Commander Antenna from the car and just had a chill-time, chatting and reminiscing with folks. See what you think! Callum.
PS – Telford and District Amateur Radio Society (TDARS) have a website: https://tdars.org.uk/

The design of the 9×9 Command Tent is (in my opinion) a work of art – and it fits on the back of the original Land Rover Defender. Flaps down. Enjoy.
I found the instructions! https://assets.publishing.service.gov.uk/media/5a74ef8640f0b65c0e845b01/20150319-FOI2015_02935_tent_enclosure.pdf

Designing a 5m extension for the tower and I’m re-commissioning one of the old coax cabinets – and other stuff…

Beaming 240 degrees from UK to VK

In this video I dive into 20-metre band (and above) and why it behaves so differently to 40m. We recap the D-layer “sponge,” explore how the F-layer splits into F1 and F2 under sunlight, and talk about take-off angles, hop lengths and long-haul DX. With graphs, a few invented words like “jigglification,” and plenty of plain English, this is a look into how 20 m propagation really works — and why it can be both magical and maddening at the same time!

(Warning: contains maths, PDFs, and raw data files. Proceed only if heavily caffeinated.)

📚 ARRL Antenna Book – Supplemental Files (23rd Edition)
https://www.arrl.org/arrl-antenna-book-23rd-edition-supplemental-files

📄 Installation Summary (PDF) – explains where the HFTA statistical elevation-angle files live
https://www.arrl.org/files/file/Antenna%20Book%20Supplemental%20Files/23rd%20Edition/Antenna%20Book%20-%2023rd%20Edition%20-%20CD-ROM%20Installation%20Summary.pdf

📊 HFTA Documentation (PDF) – dense but explains how to interpret the elevation-angle distributions
https://www.arrl.org/files/file/Antenna%20Book%20Supplemental%20Files/23rd%20Edition/HFTA.pdf

🌐 VOACAP Online (Point-to-Point Propagation) – generate your own AoA tables and predictions
http://www.voacap.com/p2p/

📚 VOACAP Technical Docs – everything you never wanted to know
http://www.voacap.com/documents.html

📰 QEX (Siwiak, May–Jun 2011) – statistical elevation angles across HF; 50% below 6°, 90% below 16°
https://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2011/QEX_5_11_Siwiak.pdf

00:00 Intro
00:20 Recap on D Layer
00:40 The F Layer
02:06 Take-Off Angles
03:07 Long Haul DX
06:39 Take-Off Angle Chart
09:03 What happens at night?
10:26 WSPR
11:49 Why Oceans Assist
12:19 Long Path to VK / ZL
13:31 When F1 and F2 Combine
15:23 Wrap-Up Conclusion

Hopefully you can have some fun watching this as I try and interview as many folks as I could inside 20-minutes. Numbers: We counted about 175 people this year – roughly same as last year. Folks talked, watched, listened and learned – more importantly – everyone had a good time.

Friday Morning Play-Time on Ham Radio