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Old April 22nd 04, 01:58 AM
Tom Holden
 
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starman wrote:
Dave wrote:

Replies interspersed

"starman" wrote in message
...
Dave wrote:

Starman,

I am no longer intending to use a folded dipole, or a
dipole of any

kind. I am currently planning to connect the
conductors at the far end of the 300 ohm twinlead but
only connect one side of the near end to the 300/75
ohm matching transformer. Will this not work? I don't
need perfection, just reasonably good (I think.)

Thanks,

Dave

So you're going to use the twinlead as if it was a
single wire. In that case, you might as well connect
the two wires in the near end too. There isn't any
advantage to keeping the wires of the near end
seperated. Connect the twinlead's near end to one wire
of the high impedance side (300-ohm) of the matching
transformer (balun).



You could feed the centre point of the horizontal twinlead as a dipole with
the pair on one leg bonded and fed by the centre conductor of the co-ax or
one side of your balun transformer and the pair on the other leg bonded and
fed by the shield of the co-ax or the other side of the balun. Leave the two
far ends separate. Cut one of the wires on each side about 1/3 or 2/3 of the
way towards the end. You could peel away the remaining wire - it's just
adding weight. What you end up with is two dipoles in parallel that are
resonant at different frequencies and will have different radiation patterns
at the same frequency. Net result will be a more omni-directional antenna
than either one alone at most frequencies.

Tom