Inverted-L antenna: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
|||
| Line 4: | Line 4: | ||
==What is it?== | |||
== Theory of Operation== | == Theory of Operation== | ||
| Line 12: | Line 14: | ||
For example: | For example: | ||
- a wire length of 128' (39m) will be resonant on 15m, 12m and 10m | * - a wire length of 128' (39m) will be resonant on 15m, 12m and 10m | ||
- a wire length of 121' (37m) will be resonant on 30m, 20m and 17m | * - a wire length of 121' (37m) will be resonant on 30m, 20m and 17m | ||
| Line 20: | Line 22: | ||
* [http://www.clive.wankling.dsl.pipex.com/l.html An inverted L for small gardens] | * [http://www.clive.wankling.dsl.pipex.com/l.html An inverted L for small gardens] | ||
* [http://www.n8mr.com/antenna.html Inverted L for 160m] | * [http://www.n8mr.com/antenna.html Inverted L for 160m] | ||
* [http://www. | * [http://www.users.icscotland.net/~len.paget/6_band_inverted_l_antenna.htm GM0ONX 6 band inverted L antenna] | ||
* [http://www.iw5edi.com/ham-radio/?the-ever-popular-inverted-l-antenna,74 The ever popular Inverted L antenna] | * [http://www.iw5edi.com/ham-radio/?the-ever-popular-inverted-l-antenna,74 The ever popular Inverted L antenna] | ||
Revision as of 01:22, 5 November 2010
Related wiki pages Antenna, Propagation, Bands
What is it?
What is it?
Theory of Operation
End-fed longwire antennas that are 5, 7, 9, 11, 13 or 15 electrical quarter-waves long will exhibit a feedpoint impedance of between 150 ohms and 250ohms. Using a 4:1 balun at the feedpoint will enable us to feed these antennas with a 50 ohm source and cable (usually coaxial cable).
Because the amateur bands are related harmonically it is possible to produce an inverted L antenna that is resonant or almost resonant on a number of bands.
For example:
- - a wire length of 128' (39m) will be resonant on 15m, 12m and 10m
- - a wire length of 121' (37m) will be resonant on 30m, 20m and 17m
External links