A Lattinate Design
Hello Fans of the Lattin persuasion,
This is a tickler design to show how little is required to come up
with similar claims of multiband operation.
First a description of the radiator:
1. 18 meters tall;
2. two #12 wires separated by 10cM;
3. wire 1 fed against Real/MININEC ground of medium characteristics;
4. wire 2 trimmed 10cM away from ground (shorter, then, than wire 1);
5. wire 1 and 2 connected with 10cM lead, 5.4 meters above ground.
3.7MHz 30 + j3 0.28dBi @ 25°
10.5MHz 70 + j7 1.34dBi @ 15°
21.4MHz 103 - j6 5.85dBi @ 55°
28.8MHz 69 + j2 6.54dBi @ 65°
If this were developed as a horizontal, it would exhibit more Z, but
the gain figures would be more useful (and certainly higher than a
Lattin design).
I would note, with some of Roy's proviso's observed, this antenna was
derived from fundamental measurements from a suite of tests, and then
scaled to this design. Scaling worked as well as expected.
I would forecast that 20M could be brought in by changing the short to
7 meters above ground (80M would lower a bit; 15M would be iffy; and
10M lost)
73's
Richard Clark, KB7QHC
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