Topband: Upside down Vertical Antenna

[Bob Eldridge]

> Because the height of my room would be more than 40 meters,
> Do anyone have experience for this kind of configuration?  I have no
> idea how to install the radials.

Many years ago operating at 4U1ITU I worked a station on 160m who said
he was using a whip antenna on his balcony. Exploring further I found he
lived at the top of an apartment building and the shield of his coax was
connected to a 134 ft (downwards) vertical. He had in effect a vertical
dipole radiating mostly from the bottom half. He had a VERY good signal.
This is a good alternative to the upside down groundplane, and there are
no radials. As a matter of fact, radials could give rise to problems
from RF fed into the power wiring of the house.

Bob VE7BS