Hello. I have an arrow that I built with "target shooting arrows" I practically used the same measurements of the original arrow and I built a band pass diplexer with which I could adjust the SWR by opening and closing the loops.

In the same way, moving the gamma match a little as necessary, I have 1: 2 in VHF and 1: 4 in UHF, it must be taken into consideration that depending on the position of the antenna the SWR varies, or at least that is what I could express. 

https://www.instructables.com/Antena-Para-Satélites-LEO-Radioaficionados/

Ignacio - TI3IES

El dom, 25 jul 2021 a las 20:21, Richard Lawn (<rjlawn@gmail.com>) escribió:
I’ve made phasing lines for two Arrow antennas. I decided to use my RigExpert to first check SWR on the antennas and found some surprising results. At 435 mhz, which is close to where much of the satellite activity is, I’m seeing 3:1, at 437 mhz it’s 2.4:1 and it’s best reading of 1.3:1 is at 440 mhz. 

I’ve successfully used a single Arrow from my summer QTH for years and it’s measurements are much better than this brand new 2nd Arrow. 

I’ve tried adjusting the match and that seems to make no real improvement in terms of lowering the resonant frequency on 70cm. 

There doesn’t seem to be such a problem on the 2 m side.

I really need to get both antennas to have a reasonable and similar SWR readings at 436 mhz before introducing the phasing lines and so far I’m having real trouble making that happen. Any suggestions will be appreciated. And yes I’ve checked to make sure I built the antenna properly with all of the elements in the right places.

Rick, W2JAZ 
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Ignacio Granados Vega - TI3IES

 Radio Club de Costa Rica
          eQSL                                AMSAT                             TI0RC

Cartago, Costa Rica
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