<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Look for the book.<o:p></o:p></p><p class=MsoNormal>“Understanding, Building, and Using Baluns and Ununs”<o:p></o:p></p><p class=MsoNormal>Jerry Sevick W2FMI<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Both are TLT devices….. Transmission Line Transformers<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Basically the jest of the book is when to use what and where/why and making your own….<o:p></o:p></p><p class=MsoNormal>Baluns go from a balanced line to an unbalanced line.<o:p></o:p></p><p class=MsoNormal>And Ununes are for unbalanced to unbalanced. (not as common)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Baluns are most commonly used to keep voltage from getting onto the outer shield of <o:p></o:p></p><p class=MsoNormal>your feed line in the case of coax, and to match that 50 ohm coax to several hundred ohms worth of antenna’s.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>To better simplify this, try not to think about what you need and when/where you should use it.<o:p></o:p></p><p class=MsoNormal>Think of how you are running the signal from your radio to the antenna.<o:p></o:p></p><p class=MsoNormal>Coax/ladder/ combo….. and what kind of antenna you have.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The book advises that if you want to know why/where/when/how to use TLT’s<o:p></o:p></p><p class=MsoNormal>you should take a graduate course in electronic transformer theory.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>BUT KEEP IT PRACTICAL……<o:p></o:p></p><p class=MsoNormal>When in reality you just need to know that your transmitter is designed for 50 ohms and you need<o:p></o:p></p><p class=MsoNormal>to ensure that as much voltage/current gets to the antenna….not on the outside of your coax<o:p></o:p></p><p class=MsoNormal>and reflected back to your radio….(your tuner helps to do that, it makes sure that the radio see’s a 50 ohm<o:p></o:p></p><p class=MsoNormal>antenna, and that your antenna sees a radio that is at the same ohms as the antenna.)<o:p></o:p></p><p class=MsoNormal>Most of the TLT’s job is to make sure that the current/voltage stays in the coax and is going out the antenna…..<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The TLT just converts one impedance to another and makes sure as much of the <o:p></o:p></p><p class=MsoNormal>power on one side gets to the other side, with little loss.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Think about your stereo….it recommends that you use 8ohm speakers, your only have 4ohm speakers.<o:p></o:p></p><p class=MsoNormal>So you get a 4 ohm resistor (tuner) and put it in series with your speaker.<o:p></o:p></p><p class=MsoNormal>Your stereo sees 8 ohms but only half the power gets to the speaker. The rest is heat in the resistor.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So instead you put two 4ohm speakers in series now your speaker is matched and no loss of power.<o:p></o:p></p><p class=MsoNormal>Simplistic view, but you get the idea.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The first question is what kind of antenna and what the designed impedance is.<o:p></o:p></p><p class=MsoNormal>Then how are you feeding it….. coax or ladder, end fed???<o:p></o:p></p><p class=MsoNormal>Then chose the proper ratio recommended for the antenna design<o:p></o:p></p><p class=MsoNormal>Build your own or buy one. Make sure it can handle the current(watts) your good to go.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>73 <o:p></o:p></p><p class=MsoNormal>Max Vaughan KF7MAX Secretary<o:p></o:p></p><p class=MsoNormal>High Desert Amateur Radio Group<o:p></o:p></p><p class=MsoNormal>PO Box 723<o:p></o:p></p><p class=MsoNormal>Bend, Oregon USA 97709<o:p></o:p></p><p class=MsoNormal>541-706-1475<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>www.hidarg.org <http://www.hidarg.org/> <o:p></o:p></p><p class=MsoNormal>maxv@horizonps.com <mailto:maxv@horizonps.com> <o:p></o:p></p><p class=MsoNormal>kf7max@arrl.net <mailto:kf7max@arrl.net> <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>HiDARG Ham Shack Group Email Addresses<o:p></o:p></p><p class=MsoNormal>· Post: MAIN@HiDARG-Shack.groups.io <mailto:MAIN@HiDARG-Shack.groups.io><o:p></o:p></p><p class=MsoNormal>· Subscribe: MAIN+subscribe@HiDARG-Shack.groups.io <mailto:MAIN+subscribe@HiDARG-Shack.groups.io><o:p></o:p></p><p class=MsoNormal>· Unsubscribe: MAIN+unsubscribe@HiDARG-Shack.groups.io <mailto:MAIN+unsubscribe@HiDARG-Shack.groups.io><o:p></o:p></p><p class=MsoNormal>· Group Owner: MAIN+owner@HiDARG-Shack.groups.io <mailto:MAIN+owner@HiDARG-Shack.groups.io><o:p></o:p></p><p class=MsoNormal>· Help: MAIN+help@HiDARG-Shack.groups.io <mailto:MAIN+help@HiDARG-Shack.groups.io><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>