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Dualband 10/15m |
DK7ZB-Dualband-Beam 10/15 m
The beam has only one feedpoint with 50 Ohm and has an open-sleeve element for 10 m
The bandwidth on 10 m is narrow, the designed part of the 10-m-Band is for SSB
10 m: 4,7 dBd 10 dB F/B
15 m: 4,2 dBd 10 dB F/B
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The Duoband-Yagi built by Franz, DL6EBH |
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The scheme of the beam with the currents for 28,5 MHz
| Number | Tube | Length |
| 1 | 25x2 mm | 200 cm |
| 2,4, 7, 9 | 20x2 mm | 150 cm (+15 cm overlap) |
| 3,5 | 16x1,5 mm | 108 cm (+ 15 cm overlap) |
| 6 | 25x2 mm | 2x 99 cm (2 cm gap in the center) |
| 8, 10 | 16x1,5 mm | 85,5 cm (+15 cm overlap) |
| 11, 14 | 20x2 mm | 100 cm |
| 12, 13 | 16x1,5 mm | 208,5 cm (+15 cm overlap) |
| 15, 16 | 16x1,5 mm | 200 cm (+15 cm overlap) |
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| Element lengths for the two bands, keep the outer tubes 15 cm longer for the overlap. The open-sleeve-element for 10 m and the reflectors can be mounted direct above the boom (metallic connection), but do not use big metallic brackets! This can detune the beam! |
Feeding with a current balun
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