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I've thought about it and the only difference is the missing paralles inductor, which I could add across the coax. Maybe?

I think the next size up is a 3/4 wave? That's not what I want!

I made some Smith plots of three antennas with a sweep from 142 MHz to 150 MHz. Markers at 144, 146, and 148 MHz counting clockwise for all plots...

The first is a straight vertical dipole direct fed with coax. This is a simple design of 12ga wire soldered to a BNC and hung from the hot end with the coax comming off at 90 degrees for 1 wavelength. It's hung indoors in the center of a room about 7 feet off the ground.

The second is the same antenna with the shield leg bent at 90 degrees, or an L dipole.

The 3rd is my now mystery antenna which is supposedly a 5/8 wave vertical element with a loading coil at the base and 4 ground radials (as pictured earlier).

The yellow dotted circle is the 2:1 VSWR circle. Anything inside is less than 2:1. The center at 1 is an ideal resistive 50-Ohm load.

Here is a bit more info about a Smith chart:

http://www.eetasia.com/ARTICLES/2008FEB/C/EEOL_2008FEB18_RFD_NETD_NT4.jpg

<blockquote data-quote="C2" data-source="post: 152121" data-attributes="member: 568">I&#039;ve thought about it and the only difference is the missing paralles inductor, which I could add across the coax. Maybe?I think the next size up is a 3/4 wave? That&#039;s not what I want!I made some Smith plots of three antennas with a sweep from 142 MHz to 150 MHz. Markers at 144, 146, and 148 MHz counting clockwise for all plots...The first is a straight vertical dipole direct fed with coax. This is a simple design of 12ga wire soldered to a BNC and hung from the hot end with the coax comming off at 90 degrees for 1 wavelength. It&#039;s hung indoors in the center of a room about 7 feet off the ground.The second is the same antenna with the shield leg bent at 90 degrees, or an L dipole.The 3rd is my now mystery antenna which is supposedly a 5/8 wave vertical element with a loading coil at the base and 4 ground radials (as pictured earlier).The yellow dotted circle is the 2:1 VSWR circle. Anything inside is less than 2:1. The center at 1 is an ideal resistive 50-Ohm load.Here is a bit more info about a Smith chart:<a href="http://www.eetasia.com/ARTICLES/2008FEB/C/EEOL_2008FEB18_RFD_NETD_NT4.jpg" target="_blank">http://www.eetasia.com/ARTICLES/2008FEB/C/EEOL_2008FEB18_RFD_NETD_NT4.jpg</a></blockquote>

[QUOTE="C2, post: 152121, member: 568"] I've thought about it and the only difference is the missing paralles inductor, which I could add across the coax. Maybe? I think the next size up is a 3/4 wave? That's not what I want! I made some Smith plots of three antennas with a sweep from 142 MHz to 150 MHz. Markers at 144, 146, and 148 MHz counting clockwise for all plots... The first is a straight vertical dipole direct fed with coax. This is a simple design of 12ga wire soldered to a BNC and hung from the hot end with the coax comming off at 90 degrees for 1 wavelength. It's hung indoors in the center of a room about 7 feet off the ground. The second is the same antenna with the shield leg bent at 90 degrees, or an L dipole. The 3rd is my now mystery antenna which is supposedly a 5/8 wave vertical element with a loading coil at the base and 4 ground radials (as pictured earlier). The yellow dotted circle is the 2:1 VSWR circle. Anything inside is less than 2:1. The center at 1 is an ideal resistive 50-Ohm load. Here is a bit more info about a Smith chart: [url]http://www.eetasia.com/ARTICLES/2008FEB/C/EEOL_2008FEB18_RFD_NETD_NT4.jpg[/url] [/QUOTE]

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