File:GP-70cm.jpg
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Summary[edit]
| Description |
Deutsch: Selbstgebaute Groundplane-Antenne für das 70cm-Band
English: UHF ground plane antenna for the 70 cm (420 MHz) band. This is a quarter-wave whip (monopole) antenna (rod at top) with four grounded quarter-wave conductors projecting down from the base of the whip to form a "ground plane". Ground plane antennas have an omnidirectional radiation pattern, radiating equal signal strength in all azimuthal directions, with the radiated power maximum in a horizontal direction and decreasing with elevation angle to zero on the antenna axis. The ground conductors serve to increase radiated power in the horizontal direction to twice the gain of a dipole, or 5.19 dB. If the ground plane wires extended out horizontally from the base of the monopole the impedance would be half that of the dipole, or 36.5 ohms. However the downward slant of the ground plane wires serves to increase the antenna impedance, so the antenna is a good match for the 50 ohm coaxial cable feedline. |
| Date | |
| Source |
Self-photographed (Original caption: " selbst fotografiert ") |
| Author | D.Derigs at German Wikipedia |
Licensing[edit]
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This work has been released into the public domain by its author, D.Derigs at German Wikipedia. This applies worldwide. In some countries this may not be legally possible; if so: D.Derigs grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law. |
Original upload log[edit]
Transferred from de.wikipedia to Commons by Wdwd using CommonsHelper.
The original description page was here. All following user names refer to de.wikipedia.
- 2008-09-06 21:14 D.Derigs 983×1376× (573698 bytes) {{Information |Beschreibung = Selbstgebaute Groundplane-Antenne für das 70cm-Band |Quelle = selbst fotografiert |Urheber = ~~~ |Datum = 06. September 2008 |Genehmigung = |Andere Versionen = |Anmerkungen = }}
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
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| current | 00:37, 31 December 2011 | | 983 × 1,376 (560 KB) | File Upload Bot (Magnus Manske) (talk | contribs) | {{BotMoveToCommons|de.wikipedia|year={{subst:CURRENTYEAR}}|month={{subst:CURRENTMONTHNAME}}|day={{subst:CURRENTDAY}}}} {{Information |Description={{de|Selbstgebaute Groundplane-Antenne für das 70cm-Band}} |Source=Transferred from [http://de.wikipedia.or |
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