RFI issues solved by accident.

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 A few years back I stumbled on a trusty trick. I have an in line line isolator. I always had all kinds of RF when I transmitted. I came through my speakers and I even messed up the image on my monitor. It was bad. And it got much worse when running my Amp. It was even shutting down my computer. Here is some helpful info. I tried everything from grounding to snap on beads on everything. This is what I stumbled on by accident and may fix your RF issues in your shack. My isolator has ferrite beads inside and is about 1 ft long and is shaped like a tube with female coax ends . I took the line isolator in my hands just as if I was water skying. I held it with both hands with the coax attached to the left and right.  Then I took it and like I say I held it like a water ski handle and I twisted it hand over hand  a few times and let the coax twist with it naturally and then tucked it away under my desk. I keyed my radio and talked and noticed  it got much better. I then pulled it back out and twisted it one more time. No more RF, None, completely gone, even with the amp on. Now ever since I learned that trick it has always worked 100 percent for me.  This worked with my Flex 5000 and now with my 6300. It was an accident and it worked like a charm.  Hope this helps you. Try it, 
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Posted 2 months ago

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Photo of mikeatthebeach .

mikeatthebeach .

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Well this means your line isolator did not have
Enough isolation

I take two or three FT-240-31 Ferrite Dounut
Course and loop 3 to 4 turns of the 50ohm

This adds to the isolation of
Keeping RF currents from traveling down the
Coax line to get into the HF Rig even with
Full power 1.5Kw onto the feed line !

Not all line isolators are the same
Palomar Engineering or Balun Solutions
Make very good 50ohm RF line isolators
With > 5K isolation

RF Works make a few with choking RF
Shield currents with 2 to 2.5 K choking

The higher the choking resistance the better !

OCF dipoles are very bad and cause RF into

73 Mike
Photo of K9SO


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I've never had any luck with those "ski-handle" isolators. Some of them simply have coils of RG-58 cable crammed up inside the tube and they burn up when running a KW. 

Mike has a good suggestion. Buy a good one. 
Photo of Tom W3FRG


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You can make your own from an unused 1:1 current balun.
Just take the twin lead end (OWL) and convert it to a connector of your choice.
You will need to open up the OWL end of the balun housing, Remove the leads from the bolts and connect the UHF connector as close as possible to the ferrite as the coax end is connected.
The current baluns that typically work best are the units that have ferrite vs coax.

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Steven Linley

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Like you, I have found loose connections ( i.e., bad soldering, no soldering, tarnished or corroded connections) to be the largest share to RF (and SWR) troubles.
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Michael Wheatley

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I vote for Palomar Engineering if you have RFI problems.  I sent them an email describing my rig, amp and antenna setup and they gave me great advice on how to fix it.

Michael - KM6LHD