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[AMPS] Enough of The Worldwide, No Holds Barred, SWR Quiz.

To: <amps@contesting.com>
Subject: [AMPS] Enough of The Worldwide, No Holds Barred, SWR Quiz.
From: kk5yy@juno.com (kk5yy@juno.com)
Date: Mon, 4 Oct 1999 19:44:48 -0700
In the same vein does anyone know how to implement filters in Juno?
I have quit this reflector before when the signal to noise went South.
There is interesting stuff to be discussed if one can get past the
jihads.

                        73 Jerry

On Tue, 05 Oct 1999 01:16:36 +0100 Pete Smith <n4zr@contesting.com>
writes:
>
>At 07:35 PM 10/4/99 -0500, bob alexander wrote:
>...
>
>>Hi Rich,
>>I think the main problem here is a lack of understanding as to what 
>a
>>standing wave is.  It is simply a voltage or current on a line that
>>changes amplitude  as you move from one end of the line to the other. 
>
>>This is due to the Z mismatch at the load/transmission line 
>junction.
>>Using your example of a 50 ohm load & 93 ohm line:
>>with 100 watts output from the generator the voltage at the 
>generator
>>end of the 93 ohm 1/2 wavelength line will be 70.71 volts @ 1.414 
>amps.
>>ExI = 100  E/I = 50 ohms.
>>
>>At the 1/4 wavelength point on the line the voltage will be 131.52 
>volts
>>@ .77 Amps and 90 dgr phase angle.  The Z at this point on the line 
>is
>>172.98 ohms...  eI=100  e/i= 172.98 ohms and the max E/ min E =
>>131.52/70.71 = 1.86 = VSWR
>>
>>At the antenna end of the line the voltage is again 70.71 v and the
>>current is 1.414 Amps  which gives 100 watts and 50 ohms.  93 ohm
>>feedline / 50 ohm load = 1.86:1 SWR.
>>
>>So, The Z looking into the cable is simply the voltage / current at 
>that
>>point on the line.  If you measure the voltage and current and
>>associated phase angles with a scope and the appropriate probes you 
>will
>>see a single voltage and a single current at each measurement point.
>
>My compliments, Bob, for adding some substance on this topic after 2 
>days
>of non-stop sniping back and forth among 3 or maybe 4 individuals.  
>Guys,
>nobody else cares about this tit-for-tat stuff.  Enough, already -- 
>back to
>amps, puleeze!
>
>73, Pete Smith N4ZR
>n4zr@contesting.com 
>
>Sometimes a tower is just a tower
>
>--
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>

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