[TowerTalk] Mosley Antenna Question

[Jim Thomson]

Date: Mon, 23 Feb 2015 11:23:38 -0600
From: "john at kk9a.com" <john at kk9a.com>
To: towertalk at contesting.com
Subject: Re: [TowerTalk] Mosley Antenna Question

The TH7 is not a bad antenna, I find it difficult to believe that a C3 out
performs it.  I had the world high 20m score in the last WPX CW using a
Hy-Gain TH7DXX

John P40A

##  sadly to say, yes indeed, a C3 will outperform a TH7-DXX.  K7LXC already ran that test.
N6BT ran the test as well, using a spectrum analyzer at the RX end, with SA set to 2db per division.

## another method that works superb is to shut OFF the  RX agc at the RX end.  Then back down the
RF gain a whole bunch.   Then apply the rx audio to standard audio test gear, or telco test gear.  That
will easily read in .1 db increments.   We had wiltron test gear at the telco I worked at, that would read in 
.05db  increments.   As long as the TX applied cxr stays constant, and the wind is not flopping eles  all over
the map, the results are dead on accurate..and repeatable.   You can apply the cxr at either ant, with
audio test gear, or sa at the opposite end.   The usual deal is to apply the cxr at the far end.....
with the sa  or audio gear connected to a xcvr or rx on the ant under test...then toggle between two
ants under test.  Like a TH7-DXX  and a C3, etc. 

##  A C3 is like 4.1 dbd....and your TH7-DXX is less than that.    The sa or audio gear just reads it as..
X on ant #1..... and   + /-  X  on  ant #2.   

## Compare a C3  with a Mosley  TA-33jr in the above format....and the results will make u gag.  Gets
even worse when a TA-32jr is used. 

Jim  VE7RF