[TowerTalk] question about a matching transformer

[Jim Thomson]

Date: Tue, 12 Jul 2016 20:20:57 -0400
From: "StellarCAT" <rxdesign at ssvecnet.com>
To: "tower" <towertalk at contesting.com>
Subject: [TowerTalk] question about a matching transformer


But there is a version of it ? shown in W2FMI?s book, that provides for a 2:1 match. And my initial thoughts are ? if I am using 2 monobanders and I can do 2:1 why would I not do it? 


Gary 
K9RX at arrl dot net

##  If using 2  x monobanders, why not just use either the traditional method, with 70/75 ohm coax and relays..... or a simple L network, and relays. 
The L network is dead simple, just a shunt C from 50 ohm input to chassis..then a series coil  from 50 ohm input connector to the 25 ohm output. 
Use some surplus  NPO  ceramic 5 kv doorknobs for the  C ....and a small  .25 inch OD  cu tubing coil, for the coil.   I have designed a few of these,
like for  40 + 15m.    And also a 50 to 16.66 ohm L network  for  3 x yagis.   Extremely low Q.  Terminate the outputs with 50 ohm plugs..and  sweep the
input across the band of interest...dead flat..right out past each end.  You cant blow up an L network.  Typ deal is to parallel a few of the NPO caps  to get the exact value required. 
Allen Bond at max gain systems had plenty of NPO caps a while ago.   Then relays used to select  top /bottom /both. 

##  If you meant  2 x tribanders, etc, then disregard. 

Jim   VE7RF