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R: [AMPS] RF Choke Forms

To: <amps@contesting.com>
Subject: R: [AMPS] RF Choke Forms
From: i4jmy@iol.it (Maurizio Panicara)
Date: Sat, 15 Jan 2000 17:29:39 +0100
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Teflon is electrically very good and relatively easy to work. Although =
expensive, it's a convenient and professional replacement for ceramic =
and glass in RF applications involving consistent power (much more than =
in amateur applications) and very high frequencies. Teflon losses, even =
when used inside a coil, stay minimal and the material itself withstands =
high temperatures too.
Do not use plastic and symilar materials were the losses increase with =
frequency (i.e. nylon) and be aware of risks when using materials which =
might burn in their composite structure if something arcs, therefore =
losing their original insulating property. (i.e. fiberglass)

73,
Mauri I4JMY

  ----- Original Message -----=20
  From: Arne Gjerning=20
  To: Amp Ref=20
  Sent: Saturday, January 15, 2000 7:13 AM
  Subject: [AMPS] RF Choke Forms


  I have been advised NOT to use Teflon, Delryn, and a few other =
insulating materials for an RF choke. Instead only use ceramic. It was =
then stated the "D" factor was the reason.=20
  OK, but why as I could not find info on this subject in the ARRL =
Handbook. Any help to point me in the direction of knowledge on this =
subject would be appreciated.  May as well learn something while =
building my amp. And I want to do it RIGHT.=20

  73 de Arne N7KA      =20


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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content=3D"text/html; charset=3Diso-8859-1" =
http-equiv=3DContent-Type>
<META content=3D"MSHTML 5.00.2014.210" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT face=3DArial size=3D2>Teflon is electrically very good and =
relatively=20
easy to work. Although expensive, it's a&nbsp;convenient and =
professional=20
replacement&nbsp;for ceramic and glass&nbsp;in RF=20
applications&nbsp;involving&nbsp;consistent power (much more than in =
amateur=20
applications) and very high frequencies. Teflon losses, even when=20
used&nbsp;inside a coil,&nbsp;stay minimal and the material itself =
withstands=20
high temperatures too.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Do not use plastic and symilar =
materials were the=20
losses increase with frequency (i.e. nylon) and be&nbsp;aware of risks =
when=20
using materials which might burn</FONT><FONT face=3DArial size=3D2> in =
their=20
composite structure if something arcs,&nbsp;therefore losing their =
original=20
insulating property. (i.e. fiberglass)</FONT></DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>73,</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Mauri I4JMY</FONT></DIV>
<DIV>&nbsp;</DIV>
<BLOCKQUOTE=20
style=3D"BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: =
0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px">
  <DIV style=3D"FONT: 10pt arial">----- Original Message ----- </DIV>
  <DIV=20
  style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>=20
  <A href=3D"mailto:gjerning@flash.net"; title=3Dgjerning@flash.net>Arne =
Gjerning</A>=20
  </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A =
href=3D"mailto:amps@contesting.com"=20
  title=3Damps@contesting.com>Amp Ref</A> </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Saturday, January 15, =
2000 7:13=20
  AM</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> [AMPS] RF Choke =
Forms</DIV>
  <DIV><BR></DIV><FONT face=3DArial,Helvetica><FONT size=3D-1>I have =
been advised=20
  NOT to use Teflon, Delryn, and a few other insulating materials for an =
RF=20
  choke. Instead only use ceramic. It was then stated the "D" factor was =
the=20
  reason.</FONT></FONT><FONT face=3DArial,Helvetica><FONT =
size=3D-1></FONT></FONT>=20
  <P><FONT face=3DArial,Helvetica><FONT size=3D-1>OK, but why as I could =
not find=20
  info on this subject in the ARRL Handbook. Any help to point me in the =

  direction of knowledge on this subject would be appreciated.&nbsp; May =
as well=20
  learn something while building my amp. And I want to do it=20
  RIGHT.</FONT></FONT><FONT face=3DArial,Helvetica><FONT =
size=3D-1></FONT></FONT>=20
  <P><FONT face=3DArial,Helvetica><FONT size=3D-1>73 de Arne=20
  N7KA&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT></FONT>=20
</P></BLOCKQUOTE></BODY></HTML>

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