X hits on this document





57 / 70


Station I was located at a single-story residence with a detached garage within twenty feet of the main house. Measurements were made using two types of antennas, a tri-band Yagi and an inverted dipole antenna.

(1) Tri-band Yagi Antenna

The first antenna studied was a tri-band Yagi antenna mounted on a pole over the garage. The antenna had three elements and was approximately 8-9 m above ground. Measurements with respect to this antenna were made in the 14 MHz band in the direction of propagation. Results of the measurements are given in Table 26.

(2) Dipole Wire Antenna

The other antenna studied was a dipole wire antenna that can best be described as a flattened, "inverted V," except that the two sections of the dipole were not straight. One end of the antenna was located at a point near a corner of the garage roof. From there it extended along the e d g e o f t h e g a r a g e r o o f t o a n o t h e r c o r n e r a n d t h e n c h a n g e d d i r e c t i o n a t a p p r o x i m a t e l y a 1 2 a n g l e toward and over the roof of the house several meters away to the point where the antenna was fed. It continued over the roof of the house and, at the opposite corner of the house, made another sharp o t u r n a b o u t 3 0 0 t o t h e b a c k y a r d o f t h e h o u s e , w h e r e i t e n d e d . T h e d i p o l e a n t e n n a w a s c l o s e t half-wave resonant at 160 m (1.88 MHz). Measurements were made at transmitting frequencies of 1.95 and 3.65 MHz, respectively. Results of the measurements are given in Table 27. o o


Document info
Document views130
Page views130
Page last viewedThu Oct 27 05:56:50 UTC 2016