[TowerTalk] question about a matching transformer

[StellarCAT]

it is 2X monos and I want to be able to select all combo's including out of 
phase... besides - it SHOULD work! It too is dead simple - supposedly.

thanks though.

g.



-----Original Message----- 
From: Jim Thomson
Sent: Wednesday, July 13, 2016 10:09 AM
To: towertalk at contesting.com
Subject: [TowerTalk] question about a matching transformer

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