grounding the 6400M

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Ok.  We (FLEX and me) think there might be a grounding problem that is causing "part" of my problems.  I.e.  Af gain going up and down. I am using a ss-30m astron power supply for the Flex.  Purchased it for the flex.  It does not have a grounding lug but does have a grounded plug.  How are your flex's grounded.  I have mine grounded to grounding bar that is hooked to my outside ground with 1/2 in braid.  ground rods are 2  twenty foot copper pipes that are hooked together with 1/2 inch braid that goes to the window feed thru.  
    Anyone got suggestions.  
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Posted 1 year ago

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K3WR - Jim

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My Astron RS-35A has a grounding lug on the bottom of the power supply, not the back as would be expected. Not sure if the SS-30M has the lug, but you may want to check.
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no lug that I can see.  Jim how do you have yours hooked to the grounding system i.e. 6400M of your flex.
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K3WR - Jim

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To avoid ground loops, my Astron RS-35A power supply, Flex 6400, AL-80B amplifier, and MFJ-989D antenna tuner are all connected to a single point in the shack. The ground cable runs outside through the wall to grounding rods.

As I mentioned earlier, I expected the power supply would have a grounding lug on the rear panel, however, it is located on the bottom of the RS-35A though.

No problems with stray RF in the shack with connecting all of the equipment to a single point. Stops ground loops, associated noise and stray RF.
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My experience on grounding.... maybe it helps,  maybe it don't.

My shack is in a building outside the house, Power run from the house 10ga wire done right,  so I thought.

I have a grounding rod at the shack at least 5ft into the ground and everything is connected to it.

I had lotta weird problems,  RF into shack, and using my 30 year old faithful walt Williams would freeze my computer and leave flex 6600 in transmit mode till I forced shutdown, my astron PS worked fine but still had rf.

So I added a cord with ground to the walt ps and a ground lug as well, so now walt ps works fine but still rf in transmit.

I was at a dead end then I wondered..... so I grounded the breaker box in the shack to the same ground rod at the shack and its been great ever since.

Never had up and down audio.....I personally wouldn't expect a ground problem for that but ive not heard what it sound like.

Good Luck.
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Bill -VA3WTB

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RF ground and electrical ground are two different things. You can not use common copper wire for RF ground, it must be flat strap wire. Never connect to an electrical ground. I am sure most understand this, but worth repeating.

I refer all to this link for reference.
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Michael Coslo

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I have 4 inch wide solid copper strapping - Is braided wire superior to that?
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KY6LA - Howard, Elmer

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I roll the dice dont have any rf issues use isolaters before my coax switches for antenna and the only ground in use is the 4 ft ground rods at the base of my vertical. All of my computer and radio gear is mostly 12vdc powered and run off mfj 4225 power supplies. The only grounds on my equipmemt is the 3 prong power cords on items not 12vdc. The flexs only ground is thru the shield of the coax when its lined up thru the coax switch.

Its been this way since 2010 and never had any issues or problems no ups's either since they beep on transmit. Everything works well and receive is quiet.

Like I said I roll the dice and take my chances the one time i did try to connect 2 units with a cable resulted in a surprise i dont wish to repeat.

Damn the torpedos .. full speed ahead!

Anytime im not using my radios power is off and they are connected to inside dummy loads on all antenna jacks and the ethernet cables unplugged.

The only issue i ever had was a brownout or surge which occurred when i was not home but my uniden 536hp was on and it took out my sd card for the scanner so i reloaded another sd card with data put it in the scanner and it fired right up normally.

And my flex 6400M does not change settings without me doing it. I hate to say it but I think you have a lemon as many issues as you have had and you got your flex 6400M just 3 days after me but only because you lived further away I belive both shipped the same day in March. Id be curious what your serial number is since yours shipped at the same time and the 1st invoice I was provided had a much lower serial number than the actual units serial number I received. Hope you have better luck ... does the lemon law in texas apply to ham rigs maybe you should check into that maybe you can get it replaced with a fresh one off the factory line since your having so many issues with it.
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Let me try this again.  Thanks everyone for the information.  I like the link to the quiet 
Station.  Lots of good info there.