All,

I'm finally putting together a vertical antenna that I hope will work
on 20 meters.

Soil is sandstone with occasional bits of granite, impossible to drill
into, it has to be
chiseled out with a hand pickaxe. I won't begin to tell you the agony
involved in
chipping out a 2 1/2 foot cubic hole into this stuff, but I managed to
do it.

But in any case forget about soil conductivity, and forget about ground
rods! There
is a single ground rod courtesy of the electrical company... probably
not at good
depth for RF but it is the only game in town.

Construction:

The ground half of the antenna starts with 5 foot of 1 inch diameter
iron pipe,
sunk halfway into hole filled with concrete. 2 1/2 half feet of iron
pipe are exposed
above the dirt. This is connected to 10 foot of 3/4 inch copper pipe.


At the 12 foot level I am mounting 4 radials, 8 foot 1 1/2 inches in
length, of 1/2 inch
diameter copper pipe. I am also mounting 4 copper guy wires, same
length, that are
intended to also work as additional radials.

The radiative half of the antenna starts with 10 foot of 3/4 copper
pipe, topped with
a 9 foot carbon fiber fishing pole. A thin copper wire of about 6 foot
3 inches in length
will be run up the fishing pole, for a total length of 16 foot 3
inches. I will be mounting
rope guy wires on the botttom of the radiative half.

The ground half and radiative half are connected together with a PVC
coupler, and make
contact with each other inside the coupler via a thick styrofoam
spacer.

Question:

This antenna is designed to hopefully work on 20 meters. If I run a
wire of 14 feet 4 1/2 inches up the fishing pole instead of the 6 foot
3 inches, and if I use guy wires of 12 foot 2 1/4 inches, leaving the
radial lengths unchanged: will I get a vertical that I can work on
both 30 and 20 meters?

Thanks in advance,

The Eternal Squire

Here is one little trick I tried a couple of years ago, when I had an
elevated 20 meter vertical with the feed point about 10 feet in the air with
4 16 ft radials. I fed it at the base with a 4 to 1 balun, mounted in
reverse. I then ran 450 ohm twin lead to the shack with a Johnson Matchbox
to tune the feeders..it worked 40 thru 10 meters (some loss on 40 but it did
work there ok).
If you try this..you need to do something to keep the twin lead from
swinging in the wind..or the impendence will change quite a bit.

wrote in message
oups.com...
All,

I'm finally putting together a vertical antenna that I hope will work
on 20 meters.

Soil is sandstone with occasional bits of granite, impossible to drill
into, it has to be
chiseled out with a hand pickaxe. I won't begin to tell you the agony
involved in
chipping out a 2 1/2 foot cubic hole into this stuff, but I managed to
do it.

But in any case forget about soil conductivity, and forget about ground
rods! There
is a single ground rod courtesy of the electrical company... probably
not at good
depth for RF but it is the only game in town.

Construction:

The ground half of the antenna starts with 5 foot of 1 inch diameter
iron pipe,
sunk halfway into hole filled with concrete. 2 1/2 half feet of iron
pipe are exposed
above the dirt. This is connected to 10 foot of 3/4 inch copper pipe.


At the 12 foot level I am mounting 4 radials, 8 foot 1 1/2 inches in
length, of 1/2 inch
diameter copper pipe. I am also mounting 4 copper guy wires, same
length, that are
intended to also work as additional radials.

The radiative half of the antenna starts with 10 foot of 3/4 copper
pipe, topped with
a 9 foot carbon fiber fishing pole. A thin copper wire of about 6 foot
3 inches in length
will be run up the fishing pole, for a total length of 16 foot 3
inches. I will be mounting
rope guy wires on the botttom of the radiative half.

The ground half and radiative half are connected together with a PVC
coupler, and make
contact with each other inside the coupler via a thick styrofoam
spacer.

Question:

This antenna is designed to hopefully work on 20 meters. If I run a
wire of 14 feet 4 1/2 inches up the fishing pole instead of the 6 foot
3 inches, and if I use guy wires of 12 foot 2 1/4 inches, leaving the
radial lengths unchanged: will I get a vertical that I can work on
both 30 and 20 meters?

Thanks in advance,

The Eternal Squire