In article . com,
"junius" wrote:

Hello folks,

Now as I understand things, with a relatively short sloper antenna for
HF, the antenna will be pretty much omni-directional. At what length
does an antenna begin to have directional characteristics?

Thanks in advance for any help...

It will happen at a high frequency. What frequency it happens at depends
on:

1. How long the wire is.
2. How high above ground it is.

--
Telamon
Ventura, California