X hits on this document





32 / 70


Station C was located at a two-story home in a suburban residential neighborhood. The station was controlled by the operator from a room on the second floor, which was near the support tower for three Yagi antennas. Electric fields due to transmissions from each of four antenna systems were measured.

(1) Tri-band Yagi Antenna (20 m band)

The first antenna system studied was a tri-band, Yagi, HF beam antenna mounted on a tower that was located immediately adjacent to the house. This antenna was located approximately 18 m above ground level and was one of three Yagi antennas mounted on the tower. Four or five elements

were used for transmission on each of the three bands. transmitting at 14.15 MHz are given in Table 12.

Measurement results for the tri-band Yagi

(2) Yagi Antenna (6 m band)

Measurements were also made with respect to an eight-element Yagi antenna with boom-length of about 4.5 m. This antenna was mounted on the tower about 3 m above the tri-band HF antenna. A frequency near 50 MHz was used for these transmissions. Measurement results for this Yagi antenna are also given in Table 12.

(3) Dipole Antenna (40 m)

Two center-fed, dipole, wire antennas were also studied at Station C. One antenna extended

from a point approximately mid-way up on the tower mentioned above, over a deck attached to the residence, and down to an attachment point near a railing on the deck. This antenna had sections

that were approximately 10 m on either side of the feed-point, resulting in half-wave resonance at

about 7 MHz.

Measurement results are given in Table 13.

(4) Dipole Antenna (160 m)

The other dipole antenna extended from a point near the top of the tower down the side of a hill on which the operator's house is located to an attachment point. Each section of this dipole extended about 38 m on either side of the feed-point, providing for an approximately half-wave antenna at 1.8 MHz. Measurement results from this dipole antenna are also given in Tables 13.


Document info
Document views229
Page views229
Page last viewedFri Jan 20 02:46:44 UTC 2017