The antenna "could" be 50 ohms resistive. As a matter of fact when the
meter is showing 1:1 and zero reactance at the point of measurement that
means it is purely resistive at that point.
You can not use the capacitance and inductance measurement functions on
one of those meters to measure them of the antenna.
Those functions are meant to measure a capacitor only by itself. The
same for inductance, only an inductor by itself.
Most of those meters just measure the impedance presented by the
capacitor at the frequency selected. That is then translated to
capacitance. Same for inductance. They measure the impedance and
translate to inductance. They really have no way of knowing if you have
a capacitor or inductor hooked to them. You have to tell it so it does
the right math for you.
73
Gary K4FMX
Radioal wrote:
> The impedance of an antenna in the real world is not 50 ohms resistive,
> which is what the meter is telling you when you attach the "calibrated"
> termination resistor.
>
> Impedance is a complex unit, consisting of resistive and reactive
> components. Rather than write an off-topic book here, I suggest you read
> the Antenna Handbook - or, if all else fails, the Autek instruction manual.
>
> Al - K8EUR
> ----- Original Message -----
> From: "Dan Sawyer" <dansawyer@earthlink.net>
> To: "amps" <amps@contesting.com>
> Sent: Saturday, February 26, 2005 4:16 PM
> 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
>>
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>>
>
>
>
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