The problem here is that both of you guys have changed the subject. The OP said
he ran a 1/4 wire from the tuner to a tree at "10 feet off the ground."
Now you have it on the ground and you're arguing about velocity factor and loss.
From: "rfi-request@contesting.com" <rfi-request@contesting.com>
To: rfi@contesting.com
Sent: Sunday, February 21, 2016 8:34 PM
----------------------------------------------------------------------
Message: 1
Date: Sun, 21 Feb 2016 16:56:21 -0800
From: Jim Brown <jim@audiosystemsgroup.com>
To: rfi@contesting.com
Subject: Re: [RFI] RFI cured with 1/4 wave wire
Message-ID: <56CA5CB5.9040105@audiosystemsgroup.com>
Content-Type: text/plain; charset=utf-8; format=flowed
On Sun,2/21/2016 10:06 AM, JW via RFI wrote:
> Has anyone said it yet - laying a 1/4 wavelength of wire out 'on the ground'
> creates an (albeit somewhat lossy) open-endedquarter wave 'stub' of somewhat
> indeterminate Z.
WAY too lossy to be useful.
> Recall, a quarter length away from the *open* end of a QW stubthe Z exhibits
> a low Z value. This is tantamount to 'walking' halfway around the perimeter
> of the Smith Chart (Z transformationor inversion in this case) and is the
> simple application of "The Quarter Wave Rule" that any RF savvy engineer
> should 'take tohis or her grave.
Of course. But of what use is such a "stub" in this application? And,
BTW, the Vp of the transmission line formed by the stub and the earth as
a return is much less than 1. Resonance of radials is also shifted by
their proximity to earth. Vp in the range of 0.7 is typical.
> This is, BTW, a common trick (open-ended QW stub or microstrip 'line') used
> on uWave MMICs to decouple Vgg and Vdd DC supply lines at millimeter wave
> lengths.
Useful on PC boards, but I can't think of why it would be useful here.
73, Jim K9YC
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