External auto tuners (LDG AT-600)

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  • Updated 1 month ago
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I am trying to run my 6400M remote and would like to use an LDG AT-600II.  When I used this with an Icom radio I was able force the tuner into tune mode remotely by using the Icom interface cable.  I know this tuner has a full auto mode but does not work as good as forcing it to tune.  Can the Flex interface with LDG?  I fear that tuning at power levels high enough to sometimes trigger the LDG could be harmful to the finals in the flex. Sometimes I need to use 50W before the mismatch is higher than 1.7. Not sure that I really want to be tuning with anymore that 10 watts.  Thoughts ?  
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Posted 1 month ago

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Mark WS7M

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Dave, I don't have that tuner but I am suprised you need so much power.

I have an HF auto which is used in Auto mode.  It tunes on 3-5 watts.  So I leave my tune slider at 5 w and hit the tune button.

You would have to check the tuner manual to see if there is a version of a USB cable that might trigger it to do what you want.
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The difference is the Hf auto reacts based on frequency change. I have one too. The ldg waits for a swr threshold before it attempts to tune
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Mark - WS7M

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Hi Dave, ya sorry... I don't have the tuner so I can't help you.
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i have the ldg 600 remote tuner,   I do NOT like the way it plays with my flex.
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I feel that if I could force it to tune it would be great.
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Arvind Mallya

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I have used the LDG AT200 Pro II Auto tuner with my Flex 5000A which did not have a built in tuner.  It works fine.  I hit the tune button on the radio and  it puts out 10 watts, which the tuner displays the tuning power and then starts the tuning steps and displays with the red LEDS the value.  The radio also displays the SWR after it is done.

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Dave - W6OVP

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My LDG Z-11 Pro works flawlessly with the FLEX 6300. At ~10 watts it triggers from the FLEX every time. I run it remote and never give it a thought. It's very important to 'train' the tuner ahead of time.
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Bob Gerzoff, WK2Y

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I have the AT-200Pro II autotuner with a 6500.  No problems.  When I do need it, I just need to make sure the ATU in the Flex is on bypass, I hit tune at about 5-10 watts and it does it's thing.
Bob, WK2Y