July 9th 15, 02:18 AM
posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: May 2011
Posts: 550
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An antenna question--43 ft vertical
On 7/8/2015 7:27 PM, Wayne wrote:
"John S" wrote in message ...
On 7/7/2015 1:44 PM, wrote:
Ian Jackson wrote:
In message , Jerry Stuckle
writes
Sure, there is ALWAYS VSWR. It may be 1:1, but it's always there.
If there's no reflection, there can be no standing wave. So, being
pedantic, there's no such thing as an SWR of 1:1!
Despite the name, VSWR is defined in terms of complex impedances
and wavelengths, not "waves" of any kind.
Actually, VSWR is defined as the ratio of Vmax/Vmin.
That's also my understanding of the definition.
In fact since SWR is defined as the maximum to minimum voltage ratio,
the "V" in VSWR is redundant.
Sort of. There is also ISWR but it is not used frequently.
But, using the voltage ratio definition, you can work yourself back
around to various source and load impedances, reflection coefficients, etc.
Sure. In fact I once built a slotted line to measure load impedances
because I could not afford to buy a vector voltmeter at the time.
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