Spiderbeam

EA1FCH escribió:

Escribió:

Hola:

Estoy haciendo una spiderbeam para 5 bandas y me estoy liando en hacer las lineas simetricas de alimentación, haber si alguien me echa una mano.

He encontrado una guía para hacer la de 3 bandas,

http://www.orari.or.id/file/buku/spiderbeam_constructionguide_english.pdf

En la página 4 creo que tienes lo que buscas.

The driven elements for 10m and 20m are fed through a short piece (approx. 50cm) of symmetric
feed line, the 15m driven element is fed directly. All feedlines are tied together in the feedpoint of the
15m driver and attached to the balun (coax choke or current balun).

The basic design principle remains the same. A 2-ele Yagi (Driver & Reflector) for 17m and a 2-ele
Yagi (Driver & Reflector) for 12m could be added without affecting the patterns on 20/15/10m. The
drivers for 17/12m are fed through short pieces of symmetric transmission line as well. These feed
lines are also attached to the common feed point, so even for 5 Bands only a single coax cable is
needed. Chapter 5 further describes additional versions for 30-17-12m (WARC) and 20-17-15m.

Saludos