SWR Advice

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mvandyke37

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Hi
I am pretty new to Ham radio, so I offer the following.
I recently strung a G5RV Pro ZS6BKW Optimized with 1:1 Balun. It is about 55 feet in the trees, but that is not the point. https://www.amateurradiosupplies.com/ProductDetails.asp?ProductCode=10098
When attempting to tune the SWR I found in to be UN-tunable.
I have a 70-80 foot piece of LMR 400 cable attached to the Balun. I disconnected the LMR-400 from the Balun and connected a 50 ohm, 10 watt resister via a SO-239 (soldered to the SO-239).
Question: If my PL-259's are solderer correctly, should I get a 1.0 SWR at the other end using a MFJ-266B to measure it with?
 

n9mxq

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Is the ladder line in "clear space"? If it's too close to other objects that could be your problem. I've had a G5RV and had no issues. So, that's where I would start.
 

mvandyke37

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Yes

The ladder line is in clear space. I read 48.8 ohms with a Multimeter but when i hook the MFJ-266B up, I can get no better than 2.1 at a low freq. As I increase the freq, it goes up >9.
Seeing as this is just a section of LMR-400, not connected to anything except a 50 ohm, 10 watt resister, should I not see close to a 1. swr across all the freqs? And if not, is it a PL-259 solder problem, (probably is with my solder skills). I did not solder the 4 holes of the PL-259 to the shield as some say to do. I watched a u-tube that stated this did not have to be done. So i will do it anyway and see if there are different results. But, in the meantime, should I get close to a 1. across all freq, when the PL-259's are soldered correctly?
70' of LMR-400 cable
 

WA0CBW

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If the 50ohm 10 watt resistor is wire wound then it becomes an inductor as the frequency increases causing it to not be 50ohms of pure resistance. This will give you the high SWR as you increase the frequency. You need a dummy load of pure resistance, not inductive resistance.
BB
 
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