Hi,

I am a new radio amateur from India (I got my license only a couple of
months back). My callsign is VU3RDD. This is my first experience with
Radio installation, so the questions and the problem I am facing may be
too silly and stupid. Neverthless... here it goes.

I live in an apartment on first floor. My inverted V for 40m and 20m
are on concrete terrace (of the 5 floor apartment). The mast is about
10 ft high. The ends of the dipole are not very symmetrically tied, as
the space constraints do not permit so. One of the ends of the dipole
is facing north and the other end towards west. Not exactly 90 degree
wide, but probably 100 to 120 degrees wide. The hight of the ends from
the terrace is not the same. I purchased a used rig last week and when
I measured the SWR, it sometimes hits 2:1, and sometimes more (if I
shout at the mic) for both 20m and 40m.

I have afew questions.

1. What are the ways to improve my antenna installation?

2. Does the concrete terrace act as ground for the antenna, and is 10
ft mast, just too short a height. The terrace itself is at around 50 ft
from the Ground.

3. I run a low loss RG213 coax from the terrace. Does the loss in the
cable contribute to the high SWR I am seeing?

Any other suggestions or general observations about this setup and hopw
I can improve the antenna setup? I also plan to learn NEC and simulate
this setup (hope it is possible to do it with NEC).

Thanks

73
Ramakrishnan, VU3RDD