birdy? or what

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  • Problem
  • Updated 2 days ago
  • (Edited)
I see what looks like a huge birdy or RFI from something.  It's still there if I disconnect the antenna.  But if I transmit even a single dit it goes away for a while.  I frequently see a much smaller thin version of this that will suddenly get larger like in the video  I can make them both go away for a while by sending a single dit.
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Stephen Hawkins NG0G

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  • puzzled

Posted 3 days ago

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Joe N3HEE

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What model Flex? Did this just start happening? What bands? There is a known issue with rfi on some 6600’s on 160 meters coming from internal power supply. Could this be coming over your DC power supply? Open a ticket with Flex support.
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Stephen Hawkins NG0G

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6400m   I have just replaced the power supply with an Astron non-switching supply to be sure that it was not caused by the other supply.  I'll know for sure by this afternoon.  When I first got the radio I noticed some small birdies on 30m when the radio was first turned on that would drift across the screen.  But the huge monster in the video just started in the last two weeks.
(Edited)
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Al Matthews

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Hello Stephen. I had, what appears to be an identical issue with my 6600m. I had strong spurs on 20m that would disappear with a click of the mic button, only to return later in the day. The spurs could be heard on 3 other xcvrs in the room, and would disappear from all three when the Flex was powered down. I tried different power supplies, cable lengths, ferrite chokes, even a battery supply. I would contact support, they are very helpful. My problem was solved by replacement, and all has been working well since. -Al
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Stephen Hawkins NG0G

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I temporarily replaced the MFJ 4230MV with an Astron 20A conventional supply.  I let it run for several hours with no evidence of the mystery birdy.  The Astron is only 16A continuous so not enough current for a permanent replacement.  QST tested a bunch of switching supplies some time ago and reported that the MFJ's were among  the quietest.   At the moment anyway it appears that the one I have is not that quiet.  I have the MFJ hooked back up so I can get on the air but I have had to kill the birdy three times in the last 45 minutes.  
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Sergey Abrikosov

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Intersting find - i saw them before but never looked dipper considering it is local QRM.
Now, I am very curious - here is one from today
https://drive.google.com/open?id=1-cVZLE7YaDk41P1qaDfJ3VmqO0G2q3E3

https://drive.google.com/open?id=1FyHvVddAD8pORpjU8HnEr-Se-A4pmA9n

Mike, Tim, please review and comment on that issue.
Thanks
Sergey, KN7K
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Sergey Abrikosov

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I am going to a ticket with Flex.
Here is another one on 20m
https://drive.google.com/open?id=1cmh6cgHLeWFnx9ch4LpMAB5dfL3Zhb7g

Sergey, KN7K