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I was the respondent who asked where 35 ohms came from. OK so ~35 ohms is from a 1/4 wave with horizontal radials (and perfect ground).
I got the numbers ( the 70 ohms) from a model with 379 wires and 690+ segments very much like Marconis blazer model only car shaped and the whip is mounted like a gutter mount on the rear passenger side.

Just looking at it doesn't a car body more closely resemble sloped radials than a flat plane?
The impedance doesn't change much whether in free space or over ground.So I don't think the ground is responsible for the high (~70 ohm) impedance reported .
Maybe the model doesn't handle the capacitance with the ground right.
I'm curious now what dead center of the roof reports. When I get a chance I'll move the whip from the rear corner to the center of the roof.

Didn't I see 65 ohms on one of Marconis pick up models?
Mine gives ~70 ohms.
Are the models showing something, did we both make the same errors ?
Marconi how many wires or segments can your EZNEC version handle ?

<blockquote data-quote="ghz24" data-source="post: 442078" data-attributes="member: 24861">I was the respondent who asked where 35 ohms came from. OK so ~35 ohms is from a 1/4 wave with horizontal radials (and perfect ground). &nbsp;I got the numbers ( the 70 ohms) from a model with 379 wires and 690+ segments very much like Marconis&nbsp; blazer model only car shaped and the whip is mounted like a gutter mount on the rear passenger side. Just looking at it doesn&#039;t a car&nbsp; body more closely resemble sloped radials than a flat plane?&nbsp; The impedance doesn&#039;t change much whether in free space or over ground.So I don&#039;t think the ground is responsible for the high (~70 ohm) impedance reported .Maybe the model doesn&#039;t handle the capacitance with the ground right. I&#039;m curious now what dead center of the roof reports. When I get a chance I&#039;ll move the whip from the rear corner to the center of the roof. Didn&#039;t I see 65 ohms on one of Marconis pick up models?Mine gives ~70 ohms.Are the models showing something, did we both make the same errors ?&nbsp;Marconi how many wires or segments can your EZNEC version handle ?</blockquote>

[QUOTE="ghz24, post: 442078, member: 24861"] I was the respondent who asked where 35 ohms came from. OK so ~35 ohms is from a 1/4 wave with horizontal radials (and perfect ground). I got the numbers ( the 70 ohms) from a model with 379 wires and 690+ segments very much like Marconis blazer model only car shaped and the whip is mounted like a gutter mount on the rear passenger side. Just looking at it doesn't a car body more closely resemble sloped radials than a flat plane? The impedance doesn't change much whether in free space or over ground.So I don't think the ground is responsible for the high (~70 ohm) impedance reported . Maybe the model doesn't handle the capacitance with the ground right. I'm curious now what dead center of the roof reports. When I get a chance I'll move the whip from the rear corner to the center of the roof. Didn't I see 65 ohms on one of Marconis pick up models? Mine gives ~70 ohms. Are the models showing something, did we both make the same errors ? Marconi how many wires or segments can your EZNEC version handle ? [/QUOTE]

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