OB5-10 almost ready

 
The OB5-10 is ready for mounting. SWR looks fine, high power balun installed.

Blue arrow : rectangular boom adaptation to fix a OB2-40 element

Red arrows : mounting holes for a Steppir element

My new antenna project : integration of Optibeam and Steppir

Because I am gradually preparing to leave the city and return to the countryside—where my station is set up—I have started a new project for a more efficient antenna system.

I will keep the mast and rotor, as well as the mini-tiltplate.
This means the tiltplate can handle a maximum wind load of 1 m² and a maximum antenna weight of 35 kg, and the telescopic mast can handle an antenna load of around 1m² during heavy weather conditions.

My new plan is as follows:

1. Have a decent monoband yagi for contests.
2. Easily switch between different bands for rare expeditions.
3. Minimize the effort needed to switch between contest and expedition goals.

Therefore, I came up with the idea of installing an Optibeam5-10, a decent monobander that meets the requirements. 
This one can be converted into a 5-element yagi on 15m or a 4-element yagi on 20m. The 7,5m boom can easily be extended to about 10m to meet the 15m/20m requirements.

I use the same boom to mount the 3 motors of the SteppIR and to quickly install the 2 elements of the Optibeam2-40.

I'm still looking for a solution for the OB1-30 dipole.

In this way, I have three different antennas using the same boom, which can remain mounted. I only need to lower the mast and switch to another system in minimal time.

Technical/mechanical preparation has started with the positioning of all possible element on the boom.

To be continued...

CQ 160m contest 2024 result

After the neck-and-neck race during the 160m contest, things didn't look so good. The raw scores indicated a second place, a consequence of my early stop on Sunday.

Raw scores : 

However, after calculating the penalty points, the result turned in my favor and I secured first place. 

The 160m band is particularly sensitive to making mistakes.
More so than in other contests, deciding whether or not to log a contact is part of the contest strategy.

Final result : 

It's always nice to compete with other compatriots. It's a pity that there are so few active Belgian contesters in CW.

Impedance of the inverted L versus number of radials

Before removing the radials of the inverted L (in fact 2x inverted L for 160m and 80m, but connected to a common balun and common radial system) to restart lawn mowing, I conducted some tests to observe the effect of the number of radials on the impedance properties of the antenna. First with 10 radials, each 21m long, then with only 4 radials, and finally with a single one. It should be noted that there is a 1:2.47 balun present in this system.

I did the test for both 80m and 160m.

End of the 160m season

 The winter of 2023-2024 is definitively over, and so is my 160m season. With 17 new worked and confirmed countries added, the counter reaches 95 confirmed DXCC entities on Topband. Only my QSO with JT1CO from 2022 remains unconfirmed.

With highlights including Yemen in FT8 and East Timor in CW, I can look back satisfied at a successful season.

Just 5 countries left on the way to the 10B-DXCC and only 4 zones needed for 160m WAZ.

High performance results with modest equipment on 30m

 

It's sometimes astonishing how much can be achieved with limited resources. Last night, I was active on 30m in FT8, using 250W and the Optibeam OB1-30 dipole antenna at a height of 15 meters. Clear, the Optibeam dipoles are very good performers.

Below are the locations where my signal was received over a period of about ten hours.

CQWPX contest : just for fun and lowband inverted L antenna testing

 

After my bad experience with using the inverted L antenna on the higher bands, contrary to the results I had with it in FT8, I made a second attempt during the WPX SSB contest on 10 meter with 100W. It was a struggle for every QSO, but ultimately, I managed to work almost all continents with an antenna that was not made for it at all. So, anything is better than doing nothing.