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[TowerTalk] Remote or in the Shack Tuners

To: <>
Subject: [TowerTalk] Remote or in the Shack Tuners
From: (
Date: Sun, 28 Oct 2001 01:14:27 EST
    In a message dated 10/19/01 3:51:42 PM Pacific Daylight Time,  
    writes: << 
        From my readings of things and listening to things, the idea of 
     near, at, or in the antenna appears to be the best thing to do for most 
     operation.  I have been looking at the screwdriver types of antennas, 
     even offer a dipole arrangement.  I think that the only drawback would 
     the lower radiation resistance.  But I have not been able to figure that 
     out or the efficiency of tuning in the shack versus tuning at the 
     for the same size antenna.  Then of course for smaller antenna tuning 
      Chris opr VE7HCB
    Chris: A tuner at the antenna has some merit for complex loads but coax 
is now the major feedline to the shack.  A remote tuner has to be tuned and 
I've done it at the tuner with 2 selsyns.  You also need a band changing 
switch.  You are suggesting something that is very inconvenient and slow.  
Using a tuner at the antenna admits you don't know how to create 50 ohms with 
a matching system like a "T match, Series Xc or Folded Dipole Techniques" for 
use in Verticals, Loops or what ever which the tuner is now required to do.  
Transfer the task of impedance matching regardless how complex it is to the 
other end of very low loss controlled open wire line length--in the shack.  
This concept has been around since the Stone Age of the Last Century and has 
never been improved on--just hot air RF.  

There are places for a Remote Tuner.  I have used one at the bottom of top 
loaded vertical on the LF's as it was voltage fed there and coax loss is low 
on LF for the rest of the way into the shack.  Here the nuisance of remote 
tuning it was worth it.  It was an 80m dipole fed with a 1/4 wave of open 
wire line.  With the feedline shorted it's an upside down ground plane with a 
hell of a low angle. There is a way to get a circular polarization and 
controlled remotely.  It was described in QST and another Radio Mag I have in 
my files in the late 40's. This could be of great value in any contact or 
contest on the LF's.  This hasn't got any play and it works.  It also reduces 
QSB from Polarization Shift.  You see there are still new/old ideas yet to 
use in the year 2001.      

In case there are any who have repeatedly missed the message, there are very 
simple techniques from the Stone Age of the Last Century where you can match 
any Z at the end of an open wire line to 50 ohms in a very low loss, a 
repeatable and recordable form.  Nobody has found better ways to do it--that 
has shown it.  I will personally reward anyone that does--with a reward of my 
choice, naturally.  Hopefully this will inspire someone to give it a try.
One of the main reasons for a tuner is to match the Z at the end of open wire 
line preferably of a certain length--to 50 ohms.  You let your fingers do the 
matching in the shack.  The antenna load can be resistive in the middle of 
the band or it can be complex on the band edges at the antenna or end of the 
feedline.  Maximum power can be transferred to either load with the least 
loss over the entire band(s) by matching the Z at the end of the open wire 
line feedline in the shack which a MB will do.  

The open wire line is the easiest to repair if damaged (coax is discarded), 
lasts for a lifetime, costs the least of any feedline in particular if you 
make it yourself.  After the settings are determined and recorded across the 
band they can be quickly selected without checking the SWR each time.   

Heathkit had a box with a "Motor Driven Series Xc Variable" that was 
installed at the feedpoint in one leg of a dipole or inverted vee for broad 
banding purposes.  Even though it was just in one side it worked just great.  
It's "just another example" of where a "Series Xc" has been used to increase 
bandwidth over the band "Very Successfully."  It can be also used to obtain a 
higher Rr value for verticals or L antennas in addition to increasing the 
bandwidth--with a single component fixed or remotely tuned.  Many seem 
brainwashed they have to use a 1/4 wave vertical length when in most cases 
the Rt is around 40 ohms.  So make it a bit longer and add a fixed series Xc 
such that it gives 50 ohms in the middle of the band.  "Increasing the Rr" is 
a more efficient way to go. Or add a motor or selsyn driven Xc to obtain the 
lowest SWR over the entire band.  Use the MFJ SWR Analyzer and a variable to 
determine the value--fixed or variable. 

This should be standard practice in this Century.  I keep getting E-Mails 
with this basic thread--"I've read your recommendations and finally decided 
to try the Series Xc in verticals or L's or the MB and open wire line on and 
on and on despite what the Poo Pooers say or those who never try it and--it 
works.  Why do they do that?"  I suggested "they ask them!"  Progress is 
tough unless the "Professional Poo Pooers" supposedly generate an idea which 
is of course very rare.  Progress is not their state of the mind. 
Regardless how far you look you will never find a more useful technique than 
a "Series Xc."  In a survey I made, it's now one of the most used by those in 
the know.  What's puzzling is why it took so long to catch on?  I guess it's 
too simple to understand and the flee markets are full of choice variable 
Xc's at a low price.  A variable Xc of the right value can do a lot of things 
in a small rotational movement often in less than 30 degrees with a component 
with virtually no loss.  I will be describing "even more of them."  Stay 
tuned.  Those who "Slam It Repeatedly" do not give any other technique that 
is more useful or what they use.  I'm still waiting.  I'll give credit where 
it's due to anyone.  I'm looking for new ideas all the time regardless who 
they come from.  Please send them to me or TT.  If you have a better way to 
do something--show it.   K7GCO

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