Date: Tue, 12 Jul 2016 20:20:57 -0400
From: "StellarCAT" <rxdesign@ssvecnet.com>
To: "tower" <towertalk@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
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|