Re: [TenTec] Ten Tec 238A settings?

["Denton" <denton@oregontrail.net>]

I do have a revamped Johnson Matchbox transmatch....Pat Buler until he 
bacame a silent key would take the old Matchboxes, recase them and add 
additional taps....but it is very sharp in tuning on 80 meters. I have 
drolled over those Palstar balanced line tuners...wonder how sharp they are 
tuning on 80 meters?
Wonder how good those MFJ balanced line tuners? Guess could go to eham and 
do some evaluation. Wish Palstar made a little 500 watt balanced line 
transmatch....
----- Original Message ----- 
From: "Rob Atkinson" <ranchorobbo@gmail.com>
To: <tentec@contesting.com>
Sent: Friday, April 11, 2008 9:53 AM
Subject: Re: [TenTec] Ten Tec 238A settings?


> I recommend that you don't use the ten tec tuner (which I do use for
> unbalanced feedlines, and it is very good for that--I am a big L network
> fan) and instead tune the 600 ohm parallel line directly with a balanced
> tuner such as the one made by Palstar.  It uses a pair of synchronized
> roller inductors and a single variable cap--each inductor is in series 
> with
> a side of the balanced line and the cap is between them and can be
> switched between the high Z and low Z sides.  Think of it as a pair of L
> networks in parallel sharing the capacitor.   The "balun" can be a 1:1 
> bead
> or coax choke on the low Z side where the impedence is always nearly 50
> ohms.  I use this arrangement and it works great.   Of course, you have to
> work out a way to bring in the balanced line to the tuner but there are 
> many
> creative ways of doing this.   We have almost exactly the same antennas 
> for
> I use a loop of roughly the same length, height and is somewhat a 
> trapezoid
> shape, fed in the middle of one long side.
>
> 73
>
> rob / k5uj
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec