Tune wont stop txing

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  • Question
  • Updated 3 years ago
Another 6700 problem.
When I push tune, the 6700 goes into transmit, but re-pushing tune does not stop the  the transmission Smart SDR locks so the only way to stop the transmission is to shut down the 6700.
This problem appears to be related as to whether the amplifier is operating, as the tune works ok without the amp operating, but with the amp on operate and at 250 watts which is the lowest I can get the tune will not shut down, in fact SmartSDR is locked.
Again this is a new problem, I could operate the 6500 at 1500watts without any problems.
Again Comments please.
Thanks
Ross
ZL1WN
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Ross Biggar

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Posted 3 years ago

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KY6LA - Howard, Elmer

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Classic case of RFI from the amp getting into the 6700

Please add lots of ferrite so.
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Al / NN4ZZ

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Ross,
I had a similiar problem with my 6700.  My problem was common mode RFI, the solution was to add ferrites.  I added them everywhere but the biggest improvement came on the coax jumper between the radio and amp.  

Scroll down to see the info on the coax jumper....

http://www.nn4zz.com/FLEX6700.htm#RF_issues_and_solutions

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
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Burt Fisher

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I never had a non Flex radio shut itself down, go into transmit by itself, it appears more shielding should have been used.
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Walt - KZ1F

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While I certainly trust Ross can speak for himself. What perplexes me with this issue is:
"Again this is a new problem, I could operate the 6500 at 1500watts without any problems."

I am at a loss for how software could let or not let spurs get into the circuitry. But if it just started happening...
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Ross Biggar

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To all of you thanks for the replies. yes it was a new problem, the 6500 worked perfectly until the 6700 arrived yesterday. I have now gone back to the 6500 while I put ferrites on everything.
Al thank you very much for your very very helpful email. I have just phoned DX Engineering and asked them to urgently send a number of ferrites, to put around everything.
I suspect the cause of the problem, is my 20m beam is very close only about 16ft away from the shack and only 35ft high, so RF is obviously getting into the shack.(Transmitting into a dummy load in the shack I have no problems at all with the transmission.)
Again, to all,  thanks for your advice.
best wishes
Ross