Jarek’s birthday and carbon pole antenna

This week I saw an alert from Jarek, @SP9MA planned for December 27th, to celebrate his 62nd birthday activating SP/BZ-062, nice idea!

I agree to do a joint activation with Jorge, EA2LU, in EA2/NV-032. There we went and activated, I was mainly SSB while Jorge did CW.

I was waiting to see a spot from Jarek popping up, but the morning developed without seeing him.

When we were about to end our activation I just tuned in 20 CW and found a station calling lonely in 14.061. It was Jarek calling CQ without any spot yet!

We did greet him and worked S2S and I raised a spot for him. Well, mission accomplished.

Then we stopped the activation and we raised a toast drinking a glass of Soplica, a cherry liquour that Jarek gave us as a gift in Friedrichshafen ham fair, back in June this year!

Na zdrowie Jarek, happy birthday!

Carbon pole antenna

Jorge suggested some time ago that perhaps a carbon fiber pole could be used as an antenna radiator. I remembered an old thread from Takeshi @JG1GPY explaining about this idea:

To my surprise, Jorge prepared his own version and brought it yesterday for a first time trial.

Jorge did some measurements at home and found the external layer of the rods are better for electrical conductivity. Although the connection between rods seems to be bad as there is no conductivity between parts, there should be any sort of coupling between the rods so that in the end the whole extended pole acts as a radiator. He wasn’t very sure this would work but decided to give it a go.

He did a neat job adding a very good conductive contact point in the base rod of a 5m long Decathlon Lakeside-5 pole, by removing with care the painting in the outer layer to bring the base material accessible.


Then he added some electrical grease, a light metal plate and finally a support to hold a BNC connector and some banana jack binding post for radials. He just added 4 short radials (about 4m long) and tested if the KX2 built in tuner could tune this combo in the summit.

SWR was very good at 18 & 21 MHz, and just acceptable (2,5:1) for 14 MHz. The rest of the bands were not worky, although maybe a future change in the radials could improve it.

He started the activation running on 21 MHz first. He kept an eye on RBN spots and to his surprise he got an automatic spot after his third call, good news! The highlight was a call from Andrei @ZL1TM. Jorge was astonished he could hear and work him so well with such an antenna!

Later Jorge ran on 18 and 14 MHz. See the spots picked by RBN network during the activation:

Jorge, is there any other interesting thing about such antenna?

Thanks everybody for the QSO and Happy new year!
73 Ignacio

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Dear Jorge and Ignacio,

Thank you very much for your participation in my birthday activation.
Yes, I reached the summit later scheduled time and it was the highest pleasure to copy calls of You both.

Many thanks.

Enjoy Soplica cherry liquor and many thanks that you kept it to underline my birthday :champagne:

Many thanks also for interesting story about carbon pole antenna :exclamation:

73, Jarek

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   Bravo Ignacio! 

You have faithfully explained the experiment with the antenna made with a carbon fiber rod.
I add just a few notes:
-As a result of the measurements I made the day before our activation I decided that it was not worth taking it to the summit…
-Then I remembered the video of JG1GPY and doing a search on the Internet I was lucky enough to find this page:

-Reading it, measurements I made and the bad electrical contact between elements of the pole are totally confirmed, but even so in these conditions,as explained in the electrical diagram that illustrates the article, the carbon fiber pole is able to radiate.
-So this information encouraged me to bring it up and test it at the summit.
-The feed point + radials is 90cm above the ground.
-Radials have great influence in the antenna resonance.

As Ignacio has explained the test has been a success (propagation was cooperative too!), for which I thank JG1 GPY for sharing his valuable information that has been so useful and enlightening for me, without it, my project never have seen the light.

I remain QRV for any clarification, thank you all for reading this review and the QSO made during
the antenna test.
Best regards 73
Jorge
EA2LU

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