antentopSince2 July

Ham Spirit
Antentop Free E-Magazine
Free Choice



Free Antentop Amateur Open Book
Antentop Album
Antentop Survey




Antentop is FREE e-magazine devoted to Antennas and Amateur Radio an

Special page devoted to

Field Antenna for the 40- meters

Custom Search


ANTENTOP- 01- 2006, # 008


Field Antenna for the 40- meters


Figure 5 shows the base of the antenna


Note by VA3ZNW: MMANA does not provide correct simulation when elements of the antenna aerial are located close to the ground. NEC- 2 for MMANA should be used in the situation. So by me the antenna was simulated in NEC- 2 for MMANA.

Figure 7 shows the diagram directivity and data for the antenna. Input impedance is near 21 Ohm, capacitor should be had 132-pF.  For matching the antenna with 50-Ohm coaxial cable an inductor 0.9 micro Henry should be turn on across antenna clips, and base capacitor C should be used on to 100-pF. Off course, the real capacity should be found at tuning of the antenna.

Figure 8 shows the circuit of this matching device.

Figure 9 shows parameters of the antenna depending on ground, above which the antenna is located. As you can see, the ground does not influence much to the parameters of the antenna. So, the antenna can be placed above any ground.

11. Average (Eps=13, Sigma=5)

12. Poor (Eps=13, Sigma=2)

13. Pastoral (Eps=13, Sigma=6)

14. Marshy land (Eps=12, Sigma=7.5)

15. Pastoral rich (Eps=14, Sigma=10)

16. Very good (Eps=20, Sigma=30)

Figure 6 shows the wire and guys of the antenna at its mast


Page 43




41 42 43 44



QRP Transceivers and PA from Accessible Parts IP for QRP Antentop Book Radio Antenna Engineering Book Antentop Printed and e- magazines



Just for Fun:

Map IP Address

Thanks for your time!

Last Updated:

August 3, 2016 16:24

Antentop Home Page

Free Antentop Open Book