Category: DX Commander

Last year, we scored over 1M points and over 1,000 contacts. Let’s see how we do this year!

We’re streaming the whole session.

Come back for more 🙂

This is an introductory, practical guide to common-mode chokes (often called "ugly baluns") aimed at everyday amateur radio operators.

The explanations are deliberately simplified to help illustrate what happens when RF current flows on the outside of the coax shield, why this can happen, and how a common-mode choke helps reduce it.

For those interested in the detailed engineering, Steve Hunt G3TXQ (SK) carried out extensive measurements on common-mode chokes and his work remains one of the best practical references available. His data was invaluable when I built my own chokes – link here:

http://www.karinya.net/g3txq/chokes/

As with most things in RF engineering, antenna balance, feedline routing, nearby objects and operating frequency all influence the amount of common-mode current present. The values mentioned in this video are simply those I’ve found to work well on my own station.

There’s LOTS to cover today:

• Project X (without giving too much away…)
• Building a true Multi-2 contest station
• A possible DX Commander remote station network
• Remote operating from anywhere
• KiwiSDRs and low-noise receive sites
• Upcoming antenna experiments
• Future video ideas
• What life behind the scenes at DX Commander actually looks like

I’d genuinely like your thoughts on one idea in particular… Would you be interested in being part of a shared remote station network? Imagine having access to a serious station in a quiet RF location without having to build it yourself.

Let me know in the comments. As always, I read all of them.

73,

Callum M0MCX
DX Commander

Band-pass filters are common in serious contest stations and multi-operator setups, but what do they actually do… and do you really need one?

In this video I explain the difference between a notch filter and a band-pass filter, how modern transceivers already include front-end band-pass filtering, and why adding an external band-pass filter can further reduce unwanted signals and harmonics.

Using my own station as an example, I show why I use an external band-pass filter when running multiple stations at the same time, and discuss whether there are any benefits for a single-operator station.

We’ll also cover:

What a band-pass filter actually does
How it differs from a notch filter
Why flagship radios have sophisticated front-end filtering
Multi-station interference and harmonic suppression
Whether an external band-pass filter is worth the investment

I’d be interested to hear your thoughts. If you use an external band-pass filter, or you’ve found it made a noticeable difference in your station, let us know in the comments.

73,
Callum M0XXT

HF all the way, any band. I don’t care. If you can hear me, let’s shoot!

In this video I build my latest homebrew 15m Yagi using fibreglass poles and insulated wire, install it at around 13 metres, measure the SWR and impedance, then put it straight on the air.

The surprise? It came out at around 45Ω, needing nothing more than a choke at the feedpoint.

Finally, it’s time for the real test… can a lightweight homebrew Yagi work DX? Amazing 🙂

If you’d like to build one yourself, the dimensions are shown at the end of the video.

73,
Callum M0XXT

A few people commented on my recent 2-VFO Stereo Monitoring video and said, "That’s diversity reception!" Not quite… But nearly…

In this video I explain the difference between deliberately listening to two antennas separately (what I’m now calling **Stereo Monitoring**) and true **Diversity Reception**, where two or more independent signal paths are combined to reduce fading and improve readability.

We’ll look at:

• Why diversity reception was developed
• Who first used it (marine, military and commercial HF operators)
• Why antennas are often spaced well apart
• Why fading occurs in the first place
• How diversity receivers work
• Why I intentionally *don’t* combine the signals in my own setup

If you’ve ever wondered why one antenna fades while another doesn’t, or why some high-end radios support diversity reception, hopefully this video will make it a little clearer.

PS – No AI was used to make the thumbnail!

73,
Callum M0XXT

#HamRadio #AmateurRadio #DiversityReception #HF #DXCommander #Shortwave

Today I’m out in the antenna field tackling a handful of maintenance jobs that have been on the list for a while. We look at why my planned 160m vertical can’t be installed quite yet, why coax and radial wires seem to disappear into the grass, a simple way to label coax so you never end up plugging the wrong antenna into the wrong radio, and my thoughts after running a Luba robot mower around a field full of antennas.

Nothing revolutionary… just a wander around the field, a few practical tips, and a chance to catch up.

Hope you enjoy it!

73,
Callum M0XXT

James M0YOM has spent the last couple of years building something rather special.

QSO Director is a brand-new amateur radio logging and station control package, written completely from the ground up. During this first look, James walks me through the software while I install it, connect it to my TS-990S and see what it can do.

We cover:

• Installation and first-time setup
• Rig control and the "buttery smooth" spectrum display
• Flexible layouts and multiple band maps
• DX Cluster integration
• QRZ lookup and logging
• Importing your existing ADIF log
• Cross-platform support (Windows, Linux & macOS)
• Cloud synchronisation and the future roadmap

This isn’t a paid promotion or sponsored video. James is a friend and fellow amateur radio operator, and I wanted to show you what he’s been working on and let you make up your own mind.

▶ 14-day free trial: https://qso-director.com

If you’ve tried QSO Director, let us know what you think in the comments. James will be reading them.

73,
Callum M0XXT