I had an 80m dipole that used 7/8" od bare aluminum CATV hardline. It
had a real nice bandwidth (at least 2x 14 ga wire) and the copperweld
center conductor is strong. To connect to the shield at the center I
used copper tube compression fittings, drilled for the coax connection.
The copperweld took the strain to a center insulator. The low conductor
loss and wide bandwidth made this a very efficient antenna. Find a CATV
contractor and ask for free reel ends, they usually scrap anything less
than 150' and larger sizes may be available. I also wonder where the
used stuff goes when it is replaced with fiber? (They probably cut it
into 10' pieces like PG&E does with used power poles :-( :-( )
I made a copper wire cage prior to this but they sure are hard to
handle, and easily get messed up by the wind.
Some of the handbooks have formulas for the shortening effect and
bandwidth increase for larger conductors.
Another possible choice rather than making a cage is wide electric fence
tape, I bought a reel of the 14 conductor stainless steel version but
haven't put it up as yet. I also just found a copper wire version,
google KIWI electric tape or electric horse fence tape. It is fairly
inexpensive, about $0.10 per foot.
Anybody using fencing tape for an antenna, let us know how it works.
Grant
KZ1W
David Jordan wrote:
>
>
> Hi Folks,
>
>
>
> Any thoughts as to whether four wires in a horizontal plane rather than four
> wires in a cage configuration would make any measurable difference as it
> relates to the 'broad-band' effect typically noted and associated with
> multi-wire cage antennas? This concept is being considered for a 75-80m
> dipole.
>
>
>
> 73,
>
> Dave
>
> Wa3gin
>
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