Great Dangling Dipoles!
 

I have a dipole hung from trees in my yard. I am going to lengthen my
dipole by hanging more wire off the end. Will I be better off to run the
wires to other trees, kind of creating a Z shape, or a C shape, or is it
just as well to allow the ends to dangle?

- Mike KB3EIA -

"Mike Coslo" wrote
I have a dipole hung from trees in my yard. I am going to lengthen my
dipole by hanging more wire off the end. Will I be better off to run the
wires to other trees, kind of creating a Z shape, or a C shape, or is it
just as well to allow the ends to dangle?

- Mike KB3EIA -

=============================

Depending on how much longer your antenna will be, you may notice a modest
improvement in signal strengths on the lowest frequency band. But you might
notice a small decrease in signal strengths on the highest frequency band.
On the other hand, you may notice nothing at all except a change in tuner
settings. But a change in tuner settings can be beneficial.

I would prefer a Z or C shape. This maintains a high average height for the
antenna and so increases the probabilty of improvement in signal strengths.

The directions in which the ends are extended will have a slight effect on
radiation patterns which you will NOT be aware of. As your dipole is
non-rotatable it won't matter anyway. For practical purposes, taking one
band with another, you can still refer your antenna as being
omni-directional.

Reciprocity ensures whatever happens on receive will apply equally to
transmit.
----
Reg, G4FGQ

Reg Edwards wrote:
"Mike Coslo" wrote
I have a dipole hung from trees in my yard. I am going to lengthen my

dipole by hanging more wire off the end. Will I be better off to run the
wires to other trees, kind of creating a Z shape, or a C shape, or is it
just as well to allow the ends to dangle?

- Mike KB3EIA -


=============================

Depending on how much longer your antenna will be, you may notice a modest
improvement in signal strengths on the lowest frequency band. But you might
notice a small decrease in signal strengths on the highest frequency band.
On the other hand, you may notice nothing at all except a change in tuner
settings. But a change in tuner settings can be beneficial.

That is the main thing I am trying to do. The tuning is pretty sharp on
80-75 meters. (the dipole is 96 feet at present) It works okay, but
since I am going to experiment with higher powers, it seemed like a more
forgiving tuner environment might be a big plus. Plus of course not
having to use as much inductance.



I would prefer a Z or C shape. This maintains a high average height for the
antenna and so increases the probabilty of improvement in signal strengths.

Makes sense.

The directions in which the ends are extended will have a slight effect on
radiation patterns which you will NOT be aware of. As your dipole is
non-rotatable it won't matter anyway. For practical purposes, taking one
band with another, you can still refer your antenna as being
omni-directional.

Reciprocity ensures whatever happens on receive will apply equally to
transmit.
----
Reg, G4FGQ


Thanks much! - Mike KB3EIA -

On the other hand, you may notice nothing at all except a change in
tuner
settings. But a change in tuner settings can be beneficial.

That is the main thing I am trying to do. The tuning is pretty sharp on
80-75 meters. (the dipole is 96 feet at present) It works okay, but
since I am going to experiment with higher powers, it seemed like a more
forgiving tuner environment might be a big plus. Plus of course not
having to use as much inductance.

========================

Mike, because you have a random length dipole you already have an idea of
the relative importance of tuner settings. Increasing antenna length nearly
always improves tuner efficiency on the lowest frequency band which, very
often, is the most used band of an antenna.

Don't concern yourself unduly with actual value of tuner roller inductance.
The main problem on the 160m and 80m bands is whether there's enough of it.
If you wish to adjust antenna length to any particular value make sure its
tunable with whatever the maximum tuner inductance happens to be.

Adjusting length of the transmission line can also be of great help.

I mention this hopefully for the benefit of less-experienced readers.
----
Reg, G4FGQ

Mike Coslo wrote in message ...
I have a dipole hung from trees in my yard. I am going to lengthen my
dipole by hanging more wire off the end. Will I be better off to run the
wires to other trees, kind of creating a Z shape, or a C shape, or is it
just as well to allow the ends to dangle?

ALWAYS add wire to the highest point on the antenna.

- Mike KB3EIA -

I don't know about "just as well", but I hv done this when space was precious
and achieved a good match to a 50-Ohm t.l.

Jack