Dualband 12/17m |
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DK7ZB-Dualband-Beam 12/17 m
The beam has only one feedpoint with 50 Ohm and has an open-sleeve element for 12 m 12 m: 4,39 dBd 11,5 dB F/B 17 m: 4,15 dBd 11 dB F/B
The Yagi built by Marcos, PY2MR
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The Yagi built by Nelu, YO9DL |
The 2-El.-Open-Sleeve-Yagi built by Phil, ON4TA
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The measurement of the SWR by Phil, ON4TA. He reports no tuning on 17 m, resonance as expected. The dip on 12 m was a little bit to high and can be shifted with the 12-m-open-sleeve-radiator. |
The Dualband-Yagi built by Tomas, OK1DXD
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The scheme of the beam with the currents for 24,9 MHz
Element lengths for the two bands, keep the outer tubes 15 cm longer for the overlap. The open-sleeve-element for 12 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
The mechanical soultions for the element holding from Nelu, YO9DL
The element construction of Marcos, PY2MR |