Disc-cone EH antenna 40 m band

 


 

    For the CQ WW CW Contest 2002 I prepared my new E-H antenna – disc-cone for a 40m band. It is a relative name, because I used not a disc, but a plate 40 x 50 cm. Why I did it? I wanted to favour the preferable contest directions  east ( VK, JA ) and west (NA, SA). Cone diameter – 40 cm, cone height – 35 cm. I mounted the cone on the four wood, wax covered stems ( see Photo_1 ). Below the plate is a polypropilene pipe 50mm diameter, where a phasing coil mounted. A matching box (L-T network) near the transceiver is also. For protection from the atmosphere moisture antenna was covered by the polyethylene sackful ( see Photo_2 ).

   Before the contest antenna was mounted 3m over the roof. But after several hours of the contest I understood, that this height is not enough. There was no problem to work the European stations. But from NA and SA I got the stations, having very good antennas only. There was a moments, when I several times called the stations from USA, but they not heard me. Is it good, when I have 300W output?

   In the light time I moved the antenna up to 6 meter over the roof ( see Photo_2 ), and in 13:25 UT I began to work in the contest again. It was much more better job. There was no problem to work JA stations. But in 15:30 UT I finished, because I had to go to my work. In the morning, November 24, I continued my contest work, and there was no problem to work any DX station. All stations of  USA, that I heard, I have in my log. Especially I enjoyed of two QSO.

1.      W7GG. His RST was 549-559 with specified for long path echo.

2.      D4B. The calling stations took place more, than 3 kHz up.

   My final score : 19 hours in the contest, 463 QSO, 84 countries, 22 zones ( see my contest log ).  What can I say about the antenna?  It makes a good job, but the height more than 1/8 wavelenght is needed for a good DX-ing.

                 UT4EK, Alex.