The antenna is a dual band vertical antenna for frequencies 260-390 MHz.
Eagle - antenna - half wave dipole at two ranges, the jumper is governed by the agreement under the cable 50 or 75 Ohms.
If you build on a metal pole chart cardioid, the gain is higher on the axis. The design is simple and made from scrap materials.
The setting is the gradual shortening of the vibrators to the desired frequency. To configure the author used the meter response X-1-50.
The setting is made by well-known methods for minimum SWR in the measuring cable length of 10-15m.
When the distance between the floors of the antenna array is equal to 600 mm length of segments connecting cables (75 Ohm) is equal to 660 mm. Then comes the 50 Ω cable to the machine.
According to the results of the test antenna is superior to the DX-60 and antenna automatic process of industrial production.
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