Richard,
I believe that you have described exactly what Steve recommended. I
have essentially the same scheme at my shack - hell, you can't use
shorter wires than reach vrom the gear to a common point! So, good
luck to you with the art of RFI suppression!
Pat, K9JAU At 08:55 AM 1/15/2016, you wrote:
>Hi Steve!
>
>Yes, indeed, this whole RFI thing looks to be not just a bitch (pardon the
>French) but also a bit more art and trial and error rather than science!
>Following is a bit more of an explanation of my present ground wire setup.
>
>Inside the shack is a ground bus (I think that is what it is called, a.k.a.,
>a "common point") that has about five terminals. Attached to each of these
>terminals is a length of 14 gauge insolated stranded copper wire that
>attaches to equipment either by its ground post (wing nut) or in the case of
>my PC and TS-2000's power supply by attaching the ground wire to a chassis
>screw (because they have no dedicated grounding post). The length of each
>of these ground wires varies from ~3' to ~7' depending on the distance of
>the respective equipment to the bus. From the bus there is a single ~6" ~10
>gauge insolated wire that goes through the wall into my garage and attaches
>to an 8' copper ground rod which is sunk into the ground with only ~6" of it
>sticking up. About 6" away from this ground rod is a second ground rod
>attached to which is AC grounding for all AC power into the shack. Then,
>both of these ground rods are connected together by heavy copper wire. This
>electrical work was done by a professional electrician.
>
>So, I do not think it is really possible to shorten the lengths of these
>separate ground wires, and then attach all of them to a single wire running
>to the bus. These wires are already about as short as they can be. I do
>understand and agree that, in most situations, the distance from the bus and
>the ends of separate ground wires is longer; in which case a single wire
>*should* bridge that distance.
>
>HTH & 73,
>Richard KK6MRH
>
>-----Original Message-----
>From: For blind ham radio operators [mailto:[log in to unmask]]
>On Behalf Of Steve Forst
>Sent: Thursday, January 14, 2016 6:41 PM
>To: [log in to unmask]
>Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power Supply?
>
>Richard,
>
>Grounding questions are one of those things in the hobby that will
>get you a multitude of contradictory suggestions.
>
>If you try them all, you will probably find one that works for you.
>
>I think all would agree that running multiple ground wires from each
>piece of gear in the shack to a ground rod is a bad idea. Usual
>practice is to run short pieces of grounding wire from each piece of gear to
>a common grounding point in the shack, with wires being as
>short as possible. Then a single heavy conductor to the ground rod.
>
>Another problem is the length of the wire (or wires in your case) from the
>equipment to the ground rod. If the wrong length, it (they) will radiate
>like an antenna.
>
>What is the length from the shack to the ground rod?
>
>
>Good luck, 73, Steve KW3A
>
>On 1/14/2016 9:08 PM, Richard B. McDonald wrote:
> > Hey Steve!
> >
> > You said it! This high power stuff is gnarly! I will try ferrite if
> > it persists. The antenna is about 40' from the shack.
> >
> > following is information about my grounding system. About 10' from
> > the shack, I have two copper 8' ground rods sunk into the ground. All
> > 120V AC into the shack is grounded to one of them. Connected to the
> > other ground rod is a terminal; attached to which are about five
> > separate 14 gauge copper wires each of which goes to equipment in the
> > shack (rig, tuner, PC, amp, etc.). then, both ground rods are
> > connected with a 10 gauge wire. For the power supply which is
> > shutting down, I just attached yet another ground wire, and I also
> > wrapped its AC power cord in tin foil. I have not yet tested to see
> > if it still shuts down with these new two grounding/shielding
>improvements.
> >
> >
> > 73,
> > Richard KK6MRH
> >
> > -----Original Message-----
> > From: For blind ham radio operators
> > [mailto:[log in to unmask]]
> > On Behalf Of Steve Forst
> > Sent: Thursday, January 14, 2016 7:27 AM
> > To: [log in to unmask]
> > Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power Supply?
> >
> > Richard,
> >
> > Welcome to the world of high power. How do you have the radio
> > grounded? How close is the antenna to the operating position?
> >
> > I would invest in some ferrites. E-bay is a good source. I would
> > clamp the AC line to the power supply, and the 12 vdc line coming out.
> > Also clamp everything connected to the radio/amp (coax, power,
> > control cables, etc.). The other school of thought is to only clamp
> > things until you find the one that is the problem.
> >
> > If your antenna is 5 feet from your operating position, things may be
> > more problematic. As Ron suggests, antenna/feedline/balun may be the
> > culprit. Sometimes this stuff is hard to solve, glad you have help on
> > site.
> >
> >
> > 73, good luck, Steve KW3A
> >
> > On 1/14/2016 9:48 AM, Richard B. McDonald wrote:
> >> Hi!
> >>
> >>
> >>
> >> In the process of setting up my Ameritron ALS-1306 amp with my
> >> Kenwood
> >> TS-2000 and an MFJ 998 tuner, sometimes RFI shuts down the TS-2000's
> >> power supply. My Elmer is convinced it is RFI because 1) it seems
> >> only to
> > happen
> >> on 20M (so far, anyway) and 2) it only happens when we crank-up the
> >> 1306 beyond ~200W. The 1306 is on a totally different, dedicated power
>line:
> >> 240V. The TS-2000's power supply is on the household's 120V. The
> >> power supply for the TS-2000 is an Astrin SS-30
> >> <https://www.hamcity.com/store/pc/SS-30-p363.htm> . So, what can I
> >> do to stop this?
> >>
> >>
> >>
> >> 73,
> >>
> >> Richard KK6MRH
> >>
> >
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