Tune OK, but talk SWR high on the Flex 6500

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The tuner seems to tune OK. But come time to MOX, SWR pegs. Checking tune again, OK. By any chance is this a symptom of RF getting into something its not suppose to? Antenna is a long wire into a 9:1 balum, then to the 6500 v2.49. Thanks, WG0C
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WG0C

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Posted 6 months ago

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AH0U

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Do you have the AFU turned on??
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George Molnar, KF2T, Elmer

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It does sound like RF getting in. Tune is at lower power; try adjusting your TX power down to match and see if that helps. End-fed wires often have RF issues. How is your station grounding?
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Steven Linley

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Yes, might be a bad ground connection at a coax connector. You can see this problem while in tune if you increase the tune power setting. Start with a tune power setting of 25 watts and if you don't see the high SWR, increase tune power, you will see it as the connection fails with power.
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WG0C

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Not sure what a AFU is. I think you meant the ATU and yes this is enabled.

Tune mode 0-100 SWR OK. In MOX mode high SWR 1-100. It's interesting however, the SWR will briefly peak full scale when un-keying in tune mode. I will need to brave the bone chilling cold here in Minnesota to see if the antenna RF ground has changed. Most likely. This is a remote base so it's a long drive to the site. Might be a few days before I can get up there.

I'll report back what I find.

Thanks of the replies. 73
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George Molnar, KF2T, Elmer

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Maybe frozen ground isn't as good a ground? Or the cold has affected the connections. 

Stay warm -- below zero wind chills here in Virginia. I left Vegas for this??