Category: DX Commander

Loking for 1,000 QSOs and 1M points

In this video I’ll show you exactly how I set up voice keying in N1MM so the computer handles the repetitive contest exchanges for me.

We’ll cover:

• Recording your own WAV files
• Where to store them inside the N1MM folder structure
• Setting up the function key macros (F1, F2, F3, etc.)
• Using concatenated WAV files to eliminate audio clicks between messages
• Sharing operator-specific callsigns and messages

I’ve also included a download link (below) containing my macro layout, recording checklist and example files to help you build your own voice keyer.

https://mega.nz/folder/hq4mGY7Z#fSPzKPMhLIGmTnxUewZl1w

Please don’t use my voice on the air… people will think I’m operating your station! 😄

If you’re new to N1MM, this should save you a lot of trial and error and get you on the air much faster for automatic voice keying.

73,
Callum M0XXT

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