75 Meter Delta Loop Beam
This antenna is fixed in direction, roughly 25/205 degrees.
It is vertically polarized, take off angle is less than 30 degrees.
The half beam width is about 56 degrees.
It changes directions by adding tuning stubs that can switch in and out.
The antenna is tuned for 3.800 Mhz but also easy to modify!
The Driven element is a total length of 264.5 feet.
The Directors (2) are 256.5 feet in total length.
The Reflectors are selectable stubs, which can be switched manually or
automatically. 12vdc SPST relays can be used.
Below is a drawing of the antenna.
Note: The lower antenna corners tie off to the ground with rope at a distance away to
pull up the lower horizontal section and to stretch the antenna out..
The dark line is the boom which will be polyurethane rope.
The elements are all wire, and the plan was to use #14 stranded insulated
copper wire. However, the electrical code calls for #14 hard drawn or copper weld
for lengths less than 150 feet. These elements will be under very little stress. They
basically are hanging from the support rope. Personally, I think the insulated wire is
a better idea, and makes it easier to see. It is pretty strong as it is. Copper weld wire
is not insulated, and is very hard to work with. One kink, and it will break easily
Also, the memory effect coming off the spool makes long lengths hard to handle!
The materials, wire, rope and insulators will be donated to the club, assuming using
#14 stranded insulated wire is accepted.
John, W6UQZ and I went to N6IJ to plot out the antenna on the property.
We have a good clear area and ground clearance between the Discone antenna pole
and pole C where the Pro 67 is. See picture below.
This is a fairly easy project, and could be done in one day.
The benefits of having a good gain and directional antenna on 75/80 meters would be
a big asset for DX to the club.
73, Scott WA6LIE
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