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Re: [Amps] Input SWR revisited

To: donroden@hiwaay.net, amps@contesting.com
Subject: Re: [Amps] Input SWR revisited
From: Gerald Williamson via Amps <amps@contesting.com>
Reply-to: TexasRF@aol.com
Date: Wed, 14 Jan 2015 15:33:14 -0500
List-post: <amps@contesting.com">mailto:amps@contesting.com>
Good question Don. You have to keep in mind that the 100 ohm load will make 
 for a 1.333 swr in the 75 ohm coax. At a length of one quarter wavelength 
the  100 ohm load impedance is transformed to 56 ohms, which is pretty close 
to 50  ohms and looks like a low swr to the radio.
 
But, the swr inside the 75 ohm coax is still 1.333 at all points along the  
cable.
 
73,
Gerald K5GW
 
 
 
 
 
 
 
 
In a message dated 1/14/2015 12:13:49 P.M. Pacific Standard Time,  
donroden@hiwaay.net writes:

Explain  the case where a 100 ohm load ( 2:1 ) can be a 1:1 swr at the   
transmitter with a length of 75 ohm cable.  I've changed the  cable  
length and improved the SWR.



Don  W4DNR



Quoting Gary Schafer  <garyschafer@largeriver.net>:

> It means that-- if you are  looking at the SWR at your radio and there is 
a
> tuner after the SWR  bridge, any changes in cable length after the tuner 
will
> show a change  in SWR at the radio if you do not touch the tuners tuning.
> This  assumes that the load on the end of the cable is not 1:1.
>
> 2nd,  the SWR will always remain the same at the radio no matter what 
length
>  of cable is used (except or cable loss) or what the load impedance is  as
> long as that load impedance remains the same.
>
>  73
> Gary  K4FMX
>
>> -----Original  Message-----
>> From: Amps [mailto:amps-bounces@contesting.com] On  Behalf Of
>> donroden@hiwaay.net
>> Sent: Tuesday, January  13, 2015 2:01 PM
>> To: amps@contesting.com
>> Subject: Re:  [Amps] Input SWR revisited
>>
>> Clear as Mud  .........
>> What does it all mean ???
>>
>> Don  W4DNR
>> _______________________________________________
>>  Amps mailing list
>> Amps@contesting.com
>>  http://lists.contesting.com/mailman/listinfo/amps
>
>


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