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Re: 435 offset yagi phasing



I found this page listed below quite interesting.  but  when it came to 
offest phasing. I'm lost a little. 

Because, of this statement

On the picture above, the centre conductor of the Coaxial-cable is 
connected to the left part of the Horizontal dipole (as shown the "+"). 
Thus, the polarity is RHCP (CW).

What happens if you are using a matching system where the dipole is not 
split?  like the awesome matching system used in M squared antennas?

The center conductor is actually going to both sides of the driven element/

Now what?

Joe WB9SBD

SV1BSX wrote:

>Andrew,
>
>don't spend your time... your questions are already answered on the
>following pages:
>
>http://sv1bsx.50webs.com/antenna-pol/polarization.html
>
>
>and also here:
>
>http://hjem.get2net.dk/ole_nykjaer/oz2oe/xyagi/build_yagi.html
>
>
>
>Happy New Year
>
>73 de Mak, SV1BSX
>
>
>
>
>----- Original Message ----- 
>From: "Andrew Rich" <vk4tec@people.net.au>
>To: "Amsat-Bb@Amsat. Org" <amsat-bb@amsat.org>
>Sent: Friday, December 28, 2007 13:25
>Subject: [amsat-bb] 435 offset yagi phasing
>
>
>  
>
>>Hi
>>
>>I have had good success with just one yagi of an offset crossed array I am
>>building.
>>
>>http://wa5vjb.com/yagi-pdf/cheapyagi.pdf
>>
>>I will add the other elements shortly.
>>
>>I am not ready to tackle the phasing part.
>>
>>I hope I have this right.
>>
>>1. The yagi's are offset, by 90 degrees so that is the offset already.
>>2. Both yagis's should then have the same length of coax coming from each
>>one.
>>3. Both yagi's will require a 1/4 wavelength of 75 ohm coax for each feed.
>>4. Remebering that the velocity factor is 2/3 in coax cable, or the speed
>>of
>>light 200 instead of 300.
>>5. Both 75 ohm feeds then join at a tee, the result of the 50 ohm antenna
>>and 70 ohm feed giving around 120 ohm
>>6. By tee'ing the two together, this should present around 50 ohm,
>>required
>>for the main feedline.
>>
>>Does that sound right ?
>>
>>( 200/435 MHz ) /4 = 11.49 cm for each feed to the tee junction of 75 ohm
>>cable.
>>
>>
>>----------------------------------------------------------------------------
>>Andrew Rich VK4TEC
>>_______________________________________________
>>Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
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>>
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>
>
>
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>_______________________________________________
>Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
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>  
>
_______________________________________________
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