Introduction Amateur radio OM Activity Contest – June 2024

OM Activity Contest – June 2024

Okno N1MM+ v OM Activity Conteste
N1MM+ window in OM Activity Contest

One of the most successful rounds of the OM Activity Contest from my point of view. Thanks to the SO2V mode, I was able to keep pace with stations using 100W of power. Števo OM7KW unusually decided to start on a different frequency and before the race and at the beginning I had a longer connection with František OM7WA, which apparently ensured, that the frequency or its proximity is not occupied by a station, who can't hear me. Franta has an excellent signal on 80m.

How to achieve an excellent signal in the OM Activity Contest?

Inverted Vee anténa
Inverted Vee anténa

Two decades of my observations speak for themselves, that horizontal loop antennas are among the best NVIS antennas (loop) Antenna. It is not for nothing that they are also called the cloud burner. I consider the second best antenna to be a dipole with power in the middle and a shape variation of the dipole in the form of an inverted V antenna.

Improving the signal by selecting the frequency

Not, I don't mean tuning the antenna or its PSV in the OM Activity Contest frequency range. I'm talking about frequency selection like this, so that the strongest stations are not near it. For example, if I choose such a frequency for my call, it will not be very successful. Why? If the signal of this station does not cause me difficulties, so the transceiver, which do not have such resistance will cause a problem. Therefore, it may be more advantageous to "squeeze" into a narrower space between weaker stations than to try a space a little further away from a strong station.

Improving the signal by adjusting the modulation

Frequency response of the Behringer XM8500
Frequency response of the Behringer XM8500

Much has already been written about a high-quality SSB signal. The basics start with choosing a microphone. Don't underestimate his choice. The Behringer XM8500 vocal microphone works for me. This dynamic microphone has a lower sensitivity, cardioid directional characteristic and wavy, frequency narrower frequency response. It naturally suppresses low frequencies, which are not necessary for communication via the radio station, and at the same time highlights the spectrum above 1 kHz, thereby contributing to the equalization of the frequency characteristic of the transmitted signal. The resulting frequency characteristic is still adjusted by the circuits of the radio station, especially the equalizer, compressor and shape of MF filters.

June round of the OM Activity Contest 2024

I already mentioned, that the first connection was with Franto OK7WA. Several more stations called right after him. But sometimes it happened, that no one called for long minutes. This made room for a search on the second receiver FT-1000MP. I made up to a quarter of the connections on it using SO2V!

The OK7WA signal from the OM Activity Contest in 2023:

However, it is not possible to stay on the frequency all the time and it may not even be reasonable. This time I was lucky and I managed to get multipliers like E thanks to Vlad OM3TLE. I also heard Slav OM0AS, but before I could call him, so he retuned and later I couldn't find him. Final ones 54 conjunction with 23 however, it gives satisfaction with multipliers for QRP performance.

Advertisement