Revision [2251]
Most recent edit made on 2008-04-24 08:48:41 by AlanBDeletions:
| Attachment | Size | Date Added | |
| IPole.pdf | 108.42 KB | 1/04/2007 7:33 pm | |
Revision [2250]
Edited on 2008-04-24 08:47:59 by AlanBAdditions:
| Attachment | Size | Date Added | |
| IPole.pdf | 108.42 KB | 1/04/2007 7:33 pm | |
Revision [1642]
Edited on 2007-03-25 20:36:54 by AlanBAdditions:
Deletions:
Revision [1336]
Edited on 2007-01-13 09:02:25 by AlanBAdditions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment without significant impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field. For 20 meters and up a smaller version can be constructed from Buddipole parts, see the VerticalBuddIPoleAntenna page.
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and avoid proximity to personnel. Ten feet is the recommended minimum lower element height. The following examples are all possible with tree supports ten feet or so above the apex.
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and avoid proximity to personnel. Ten feet is the recommended minimum lower element height. The following examples are all possible with tree supports ten feet or so above the apex.
- 40m 27 27 (modelled, apex at 40-50+ ft)
- 80m 53 53 (modelled, apex at 65-75+ ft)
- 160m 71 142 (modelled, apex at 80-90+ ft)
Deletions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with no apparent impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field. For 20 meters and up a smaller version can be constructed from Buddipole parts, see the VerticalBuddIPoleAntenna page.
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and avoid proximity to personnel. Ten feet is the recommended minimum height. The following examples are all possible with 100 foot tree supports.
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and avoid proximity to personnel. Ten feet is the recommended minimum height. The following examples are all possible with 100 foot tree supports.
- 40m 27 27 (modelled, apex at 50 ft)
- 80m 53 53 (modelled, apex at 75 ft)
- 160m 71 142 (modelled, apex at 90 ft)
Revision [1296]
Edited on 2007-01-10 10:12:31 by AlanBAdditions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with no apparent impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field. For 20 meters and up a smaller version can be constructed from Buddipole parts, see the VerticalBuddIPoleAntenna page.
Deletions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with no apparent impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
Revision [1287]
Edited on 2007-01-08 18:33:54 by AlanBAdditions:
- 12 or 14 gauge hard-drawn copper or copper-clad steel are recommended for strength
Deletions:
- 12 gauge THHN or 14 gauge hard-drawn copper or copper-clad steel are recommended for strength
Revision [1283]
Edited on 2007-01-08 00:07:43 by AlanBAdditions:
Feeding the vertical section in the middle is inconvenient. Feeding lower down results in a better mechanical system. The impedance rises slowly with these large hats so it is still below 50 ohms. If coax is used to feed it must have a very effective balun to avoid upsetting the low angle vertical radiation pattern with a deep null straight up.
Deletions:
Feeding the vertical section in the middle is inconvenient. Feeding lower down results in a better mechanical system. If some care is taken a 300 ohm feed location may be found.
Revision [1282]
Edited on 2007-01-07 23:59:59 by AlanBAdditions:
- 160m 71 142 (modelled, apex at 90 ft)
Deletions:
- 160m 60 180 (est)
Revision [1281]
Edited on 2007-01-07 23:50:37 by AlanBAdditions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with no apparent impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
Deletions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with only a small impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
Revision [1280]
Edited on 2007-01-07 23:49:46 by AlanBAdditions:
- 40m 27 27 (modelled, apex at 50 ft)
Deletions:
- 40m 26 26 (est)
Revision [1279]
Edited on 2007-01-07 23:42:11 by AlanBAdditions:
- 40m 26 26 (est)
- 80m 53 53 (modelled, apex at 75 ft)
- 160m 60 180 (est)
Deletions:
- 40m 32 32
- 80m 40 80
- 160m 60 180
Revision [1250]
Edited on 2007-01-05 09:03:31 by AlanBAdditions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and avoid proximity to personnel. Ten feet is the recommended minimum height. The following examples are all possible with 100 foot tree supports.
Deletions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and prevent proximity to personnel. Ten feet is the recommended minimum height. The following examples are all possible with 100 foot tree supports.
Revision [1249]
Edited on 2007-01-05 00:15:40 by AlanBAdditions:
Off Center Feed
Feeding the vertical section in the middle is inconvenient. Feeding lower down results in a better mechanical system. If some care is taken a 300 ohm feed location may be found.
Feeding the vertical section in the middle is inconvenient. Feeding lower down results in a better mechanical system. If some care is taken a 300 ohm feed location may be found.
Revision [1248]
Edited on 2007-01-04 23:31:26 by AlanBAdditions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and prevent proximity to personnel. Ten feet is the recommended minimum height. The following examples are all possible with 100 foot tree supports.
Deletions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and prevent proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Revision [1247]
Edited on 2007-01-04 23:30:19 by AlanBAdditions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and prevent proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Deletions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and keep above proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Revision [1246]
Edited on 2007-01-04 23:29:43 by AlanBAdditions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to minimize coupling to earth and keep above proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Deletions:
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to reduce coupling to earth and keep above proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Revision [1245]
Edited on 2007-01-04 23:28:54 by AlanBAdditions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for straightforward field deployment with only a small impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
Deletions:
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for simple field deployment with only a small impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
Revision [1244]
Edited on 2007-01-04 19:01:39 by AlanBNo differences.
Revision [1243]
Edited on 2007-01-04 19:01:32 by AlanBAdditions:
Example Dimensions (approximate)
- Band Ht Wid (ft)
- 40m 32 32
- 80m 40 80
- 160m 60 180
Deletions:
Example Dimensions (approximate)
Band Ht Wid (ft)
40m 32 32
80m 40 80
160m 60 180
Band Ht Wid (ft)
40m 32 32
80m 40 80
160m 60 180
Revision [1242]
The oldest known version of this page was edited on 2007-01-04 19:01:18 by AlanBThe Vertical I-Pole Antenna
Vertical Dipoles are very effective on the lower frequencies (160 through 40 meters), but mechanically somewhat unwieldy due to their extreme height. Various techniques are used to reduce the height (such as loading coils), but many of these techniques reduce efficiency and bandwidth, or are mechanically complex. The Vertical I-Pole provides a solution to the height problem without significant loss of bandwidth or efficiency and retains mechanical simplicity. This result is realized by using capacity hats on both ends. Using single wire hats maintains the mechanical simplicity required for supporting between trees for simple field deployment with only a small impact on omnidirectionality. A pair of tall trees and a Pneumatic Antenna Launcher can be used to set up a very effective Vertical I-Pole rapidly in the field.
For resonant operation the width plus height should be approximately a half wave. A modelling program can be used to fine tune the dimensions in advance if resonance is desired. Resonance is not required if fed with balanced line and a tuner the antenna can be tuned on frequencies above and slightly below the halfwave with good efficiency. The lower arm should be high enough to reduce coupling to earth and keep above proximity to personnel. 10 feet is a good minimum height. The following examples are all possible with 100 foot tree supports.
Example Dimensions (approximate)
Band Ht Wid (ft)
40m 32 32
80m 40 80
160m 60 180
Mechanical Issues
- 12 gauge THHN or 14 gauge hard-drawn copper or copper-clad steel are recommended for strength
- Allow sag in the antenna to reduce stress
- Keep feedline and vertical section lightweight to reduce top wire loading (uninsulated wire is lighter)
- Avoid coax feed as it is heavy and lossy in multiband operation (and balun weight is at a bad spot)
References
- Pneumatic Antenna Launchers∞
- W4RNL Antenna Analysis Papers∞
- EZNec
- 4nec2
AlanB, WB6ZQZ
CategoryHamRadio CategoryFieldDay