Received-SPF: none
 receiver=logan.com; client-ip=98.139.44.184; envelope-from=ceengland@bellsouth.net
Message-ID: <4E187DAE.4010801@bellsouth.net>
Date: Sat, 09 Jul 2011 11:11:26 -0500
From: Charlie England <ceengland@bellsouth.net>
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110516 Thunderbird/3.1.10
MIME-Version: 1.0
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: sheilded plug wires
References: <list-5046805@logan.com>
In-Reply-To: <list-5046805@logan.com>
Content-Type: multipart/alternative;
 boundary="------------070802050307060707020408"

This is a multi-part message in MIME format.
--------------070802050307060707020408
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

To expand on that for the electron-challenged, an inductor is 
effectively a frequency dependent resistor. The higher the frequency, 
the higher the resistance. So, the fundamental pulse to the plug makes 
it through (though slowed slightly), while the harmonics (noise) that 
were generated  can't get past the extra resistance presented to them.

The reverse is true for a capacitor. That's one of the reasons why you 
see capacitors with one leg tied to the power supply & the other to 
ground. The capacitor blocks DC but passes higher frequencies (the 
noise) to ground.

I have no doubt that the above will make physicists cringe, but it's 
close enough to working knowledge for us builders to use.

Charlie

On 07/09/2011 08:28 AM, Tracy wrote:
> In this case "shielded" is the wrong term.   The spiral wire does not 
> actually shield the noise, it prevents the noise from being 
> transmitted.    It acts as an inductor to prevent the propagation of 
> the noise generated at the spark gap from propagating up the wire.
>
> Tracy
>
> Sent from my iPad
>
> On Jul 9, 2011, at 2:09 AM, Lehanover@aol.com 
> <mailto:Lehanover@aol.com> wrote:
>
>> It has to do with the resistance of the long thin Monel wire. An 
>> impedance mismatch and inductive reactance. What the mechanism is I 
>> do not know. That is why Tracy is here, to explain such matters.
>> Lynn E. Hanover
>> In a message dated 7/8/2011 11:08:09 P.M. Paraguay Standard Time, 
>> SBoese@uwyo.edu <mailto:SBoese@uwyo.edu> writes:
>>
>>     My last massage got a little garbled, the way I have my wires
>>     configured now, the conductor and spiral wrap are exposed and
>>     folded under the crimped teminal ends, so aren't both the
>>     conductor and the spiral wrap acting as a conductor? What is
>>     doing the shielding?
>>     Brian Trubee
>>


--------------070802050307060707020408
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <meta content="text/html; charset=ISO-8859-1"
      http-equiv="Content-Type">
    <title></title>
  </head>
  <body bgcolor="#ffffff" text="#000000">
    To expand on that for the electron-challenged, an inductor is
    effectively a frequency dependent resistor. The higher the
    frequency, the higher the resistance. So, the fundamental pulse to
    the plug makes it through (though slowed slightly), while the
    harmonics (noise) that were generated&nbsp; can't get past the extra
    resistance presented to them.<br>
    <br>
    The reverse is true for a capacitor. That's one of the reasons why
    you see capacitors with one leg tied to the power supply &amp; the
    other to ground. The capacitor blocks DC but passes higher
    frequencies (the noise) to ground.<br>
    <br>
    I have no doubt that the above will make physicists cringe, but it's
    close enough to working knowledge for us builders to use.<br>
    <br>
    Charlie<br>
    <br>
    On 07/09/2011 08:28 AM, Tracy wrote:
    <blockquote cite="mid:list-5046805@logan.com" type="cite">
      <div>In this case "shielded" is the wrong term. &nbsp; The spiral wire
        does not actually shield the noise, it prevents the noise from
        being transmitted. &nbsp; &nbsp;It acts as an inductor to prevent the
        propagation of the noise generated at the spark gap from
        propagating up the wire.</div>
      <div><br>
      </div>
      <div>Tracy<br>
        <br>
        Sent from my iPad</div>
      <div><br>
        On Jul 9, 2011, at 2:09 AM, <a moz-do-not-send="true"
          href="mailto:Lehanover@aol.com">Lehanover@aol.com</a> wrote:<br>
        <br>
      </div>
      <blockquote type="cite">
        <div>
          <font id="role_document" color="#000000" face="Arial" size="3">
            <div>It has to do with the resistance of the long thin Monel
              wire. An impedance mismatch and inductive reactance. What
              the mechanism is I do not know. That is why Tracy is here,
              to explain such matters.</div>
            <div>&nbsp;</div>
            <div>Lynn E. Hanover</div>
            <div>&nbsp;</div>
            <div>
              <div>In a message dated 7/8/2011 11:08:09 P.M. Paraguay
                Standard Time, <a moz-do-not-send="true"
                  href="mailto:SBoese@uwyo.edu">SBoese@uwyo.edu</a>
                writes:</div>
              <blockquote style="border-left: 2px solid blue;
                padding-left: 5px; margin-left: 5px;"><font
                  style="background-color: transparent;" color="#000000"
                  face="Arial" size="2"><font color="black" face="arial"
                    size="2">
                    <div>My last massage got a little garbled, the way I
                      have my wires configured now, the conductor and
                      spiral wrap are exposed and folded under the
                      crimped teminal ends, so aren't both the conductor
                      and the spiral wrap acting as a conductor? What is
                      doing the shielding?</div>
                    <div>&nbsp;</div>
                    <div>Brian Trubee<br>
                    </div>
                  </font></font></blockquote>
            </div>
          </font>
        </div>
      </blockquote>
    </blockquote>
    <br>
  </body>
</html>

--------------070802050307060707020408--