Looking at the myantennas.com web site, he has a set of end fed multi-band
half wave antennas which he claims exhibit low swr on several adjacent
bands. He says nothing about matching networks but says " no tuner
required"
Does anybody have experience with any of his "EFHW" antennas, and if so how
does he do it?
You just have to have some kind of a matching network for an end fed half
wave.
tom Fowle WA6IVG
On Sat, Jan 16, 2016 at 11:00:08PM -0600, Dr. Ronald E. Milliman wrote:
> The Common Mode Choke I use is the CMC-130-3K produced by and available from
> MyAntennas.com. Here is the direct URL:
>
> http://myantennas.com/wp/product/cmc-130-3k/
>
> These Common Mode Chokes are produced by Danny Horvat who is an interesting
> fellow. He produces a variety of antennas and antenna related products.
>
> Ron, K8HSY
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Tom Behler
> Sent: Saturday, January 16, 2016 10:05 AM
> To: [log in to unmask]
> Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power Supply?
>
> Richard.
>
> I'd be interested in what kind of common mode RF chokes you get, or what
> others on the list use. and where they can be gotten.
>
> I, too, have some RF issues here on certain bands, although they are not as
> serious as what you are dealing with.
>
> Tom Behler: KB8TYJ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Richard B. McDonald
> Sent: Saturday, January 16, 2016 10:52 AM
> To: [log in to unmask]
> Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power Supply?
>
> Hi Tom!
>
> No, I do not have a common mode choke, but I think I am going to get one!
>
> 73,
> Richard KK6MRH
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Tom Fowle
> Sent: Friday, January 15, 2016 5:59 PM
> To: [log in to unmask]
> Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power Supply?
>
> richard,
> I forget if you said whether you have a common mode choke in the coax to
> your antenna?
> That's always a first try at keeping R.F. out of where it doesn't belong.
>
> Also you could try disconnecting the ground from the power supply, and/or
> making that individual ground wire a bit longer and taking a few turns of it
> through a ferite core near the supply.
>
> Yes it's closer to sorcery than science! <GRIN>
>
> good luck
> Tom Fowle WA6IVG
>
> On Fri, Jan 15, 2016 at 11:11:43AM -0500, Steve Forst wrote:
> > Dave,
> >
> > I'm not an electrician or a doctor (although I played one when I was
> > 6), but my understanding is that the National Electric Code (NEC) mandates
> > that all grounds should be bonded to the electric mains ground.
> >
> > I'm sure others with more experience will chime in.
> >
> > 73, if you are on the 20 meter net Sunday, try the processor, it
> > brought you up a bit on 40 last Sunday when you were chatting with
> Junior.
> > Steve KW3A
> >
> >
> >
> >
> >
> > On 1/15/2016 10:54 AM, David Weigel wrote:
> > > Hi, Richard, Steve and readers:
> > > It is always interesting to learn about the various ways to reduce
> > > or eliminate RF in the radio room. I was wondering if it would be a
> > > better practice or at least worth a try to NOT connect the 2 ground
> > > rods together electrically. I was thinking that the 120 VAC ground
> > > rod might create a low volume "buzz" or spiky noise, coming back on
> > > the separate equipment-ground rod pathway. But I could be wrong.
> > > And, as Steve suggested earlier, my preference is to place ferrite
> > > clamps on all cables, jumpers, etc. "Line Isolators are recommended
> > > by The Radio Works, particularly when there are extraordinary length
> > > connections to ground rods, or when there can be no ground rodds
> > > whatsoever. although I have never used them. Just stirring the pot,
> slowly.
> > >
> > > Dave Weigel KD4JEZ
> > >
> > > -----Original Message-----
> > > From: For blind ham radio operators
> > > [mailto:[log in to unmask]]
> > > On Behalf Of Steve Forst
> > > Sent: Friday, January 15, 2016 10:16 AM
> > > To: [log in to unmask]
> > > Subject: Re: How to Stop RFI from Shutting Down My TS-2000's Power
> Supply?
> > >
> > > Ok, I misunderstood. The way I had read the other post, I had thought
> > > that you were running several wires from the shack to the outside rod,
> > > one for each piece of gear. That wouldn't be a good idea. Sounds
> > > like you have a good handle on the ground side of things.
> > >
> > > 73, Steve KW3A
> > >
> > > On 1/15/2016 9:55 AM, Richard B. McDonald 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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