This is correct with the RF-1. They do make a more expensive model which
gives real and imaginary parts directly however...
Sincerely,
Dr. William J. Schmidt, II K9HZ
Trustee of the North American QRO - Central Division Club - K9ZC
Email: bill@wjschmidt.com
WebPage: www.wjschmidt.com
"If computers get too powerful, we can organize them into a committee; that
will do them in." -- Bradley's Bromide
----- Original Message -----
From: "Georgens, Tom" <tom.georgens@engenio.com>
To: "'Dan Sawyer'" <dansawyer@earthlink.net>; "amps" <amps@contesting.com>
Sent: Saturday, February 26, 2005 9:49 PM
Subject: Re: [Amps] close to off topic - how to read antenna R + jX ??
>
> Dan -
>
> It is my understanding that the RF-1 displays just the magnitude of the
> impedance vector. It cannot directly separate the resistive and reactive
> elements into R + jX. Instead, it reads !Z! or the square root of the sum
> of R squared and X squared. When you measure a pure 50 ohm resistance,
> the reactance is zero and the Z (what you read) is 50. When you press the
> C button, you get the value of capacitor that will yield that magnitude of
> impedance at the selected frequency. Likewise when you press the L
> button.
>
> To be clear, you cannot directly read resistive, capacitive or inductive
> components of a complex impedance on the meter unless there is a pure
> resistance, capacitance, or inductance.
>
> That said, I believe the website has a set of equations from which R + jX
> can be derived from the Z and SWR measurements. This is not in the
> manual.
>
> Hope that helps a little
>
> 73, Tom W2SC
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
> Behalf Of Dan Sawyer
> Sent: Saturday, February 26, 2005 1:17 PM
> To: amps
> Subject: [Amps] close to off topic - how to read antenna R + jX ??
>
>
> All,
>
> I have become interested in leaning more about what is actually going on
> at the antenna. I have a vertical and would like to measure it.
>
> First I have an Autek RF-1. It measures swr, Z, L, and C at a preset f.
> I am not certain what the L and C are reading. When I measure a 50 Ohm
> terminator at 7.2 MHz it actually reads a Z of 50 and an SWR of 1.0.
> However the L and C readings are of 2 uH and 2500 pf. What are these
> actually measuring? The values are very close to those from the antenna.
>
> How can I actually measure the L and or C component of the antenna? If I
> use an impedance bridge at the frequency will it measure L (or C)?
>
> I hope this is close enough to topic.
>
> Dan
>
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