[Top] [All Lists]

[TowerTalk] Autek RF-1 Analyst

To: <>
Subject: [TowerTalk] Autek RF-1 Analyst
From: (Bowen, Arlan)
Date: Fri, 19 Nov 1999 07:23:28 -0500
I have owned an RF 1 for several years. Initially, I tried to measure and
convert the R and X readings, then build L networks to match by plugging my
readings into L network program from ON4UN or the ARRL Antenna book. I
finally gave up on that method because it just was not accurate enough.
Sometimes it was not even close. 

On suggestion of AA4Z, I subsequently built a small universal network that
can be made into any of 4, L network configurations. I put the L network
right at the base of the vertical or at the end of a feedline where
matching is needed. I then adjust the L network components to the proper
configuration for a match. After that, I measure the values of L and C with
the Autek and construct the network with heavy duty components.

This method works correctly the first time, unlike my efforts to use
measurements plus mathematics to get the values. In addition, it always
gives the proper configuration for the L network, something that the
"measured" numbers in the above programs, never provided. In the long run,
this method is best and fastest.

I use a small rotary inductor of about 18 microhenries and a large variable
capacitor of around 1500 pF. The capacitor is an old 5 section one salvaged
from military gear. You could also use a smaller variable and parallel
fixed capacitors with a switch. 

The L network configurations are shown in ON4UN's Low Band book and in the
ARRL Antenna Book, among others.

At 02:51 PM 11/18/99 EST, you wrote:
>I seem to have lost my manual for the Autek RF-1 analyst.
>If someone was so great as to put one on a scanner and mail a copy (PDF) to 
>me -  that would make me VERY HAPPY...!
>otherwise... can someone tell me if and how can I measure complex impedances 
>(like 44 -j28 Ohms) with the RF-1? I think there was something explained in 
>the manual about how to combine results from Z measurements and L/C 
>measurements to find out the complex impedance...Or is this just wishful 

FAQ on WWW:     
Administrative requests:

<Prev in Thread] Current Thread [Next in Thread>