Steve:
I've contacted the maker of the antenna, and he has no other suggestions
aside from being extremely sure that I have a good grounding system, which I
think I do.
I don't really have a convenient way to try the rig on a 12-volt battery
right now, but I may be able to work out something.
The quarter wave length of insulated wire attached to the ground lug of the
rig sounds intriguing. I assume that a quarter wave for 20 meters would be
about 8 feet? What gauge of wire should I consider, and where to I attach
the other end?
Thanks, and 73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, July 28, 2006 3:01 PM
Subject: Re: continuing RFI problems in travel trailer
> Tom,
> A lot of good advice thus far. Can you take the rig off the a.c.
> completely, by trying it on a 12 volt battery and see what happens?
>
> What about a quarter wave of insulated wire for 20 meters attached to the
> ground lug of the rig? Some people have success with this in a home
> station where there is rfi on a particular band, but don't know how it
> would play in a trailer situation.
>
> Have you contacted the mfg of the antenna? He may have heard of
something
> similar from other customers and perhaps has an answer.
>
>
> Good luck, Steve KW3A
>
>
>
> ----- Original Message -----
> From: "T Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, July 28, 2006 1:19 PM
> Subject: continuing RFI problems in travel trailer
>
>
> > Hi, all.
> >
> > I hate to bug everyone again about this, but I continue to have a
nagging
> > RFI problem in the 18-foot Fleetwood Pioneer travel trailer that my XYL
> > and
> > I recently purchased.
> >
> > To review, when operating HF, I tend to cut off the air conditioner
> > whenever
> > keying up on CW. I don't trip the GFI circuit breaker--I just cut the
> > unit
> > off, and it eventually re-sets itself and resumes normal operation
within
> > a
> > few minutes. The problem occurs mainly on 20 meters, although it does
> > occur
> > on certain frequencies in other bands as well. I have found the problem
> > to
> > occur even when reducing my power from 100 watts, say to 50 watts.
> >
> > My HF rig is an Icom 718, and my antenna is a Predator screw-driver-type
> > antenna mounted on the back of the trailer. I use a device called the
> > Turbo-tuner, to be sure that the antenna is indeed resonant on my
> > operating
> > frequency.
> >
> > The antenna itself is grounded to the bumper of the trailer, and I have
> > installed two other grounds. One is a ground from the 718 to the frame
of
> > the trailer, and the other ground is an earth ground that runs from the
> > rig
> > to a grounding stake outside of the trailer.
> >
> > I am getting more and more stumped with this problem, although I have
two
> > additional thoughts. Let me run them by you here; I just don't want to
> > spend more money unnecessarily on this problem:
> >
> > 1. I run the 718 with an MFJ Mighty Lite switching power supply. I
think
> > it's the 4125--it has 25 amps surge, and 22 amps continuous. Could this
> > type of supply be causing the problem via some sort of stray current
flow?
> > Should I try an old transformer-type supply, such as an Astron RS20, to
> > see
> > if the problem disappears?
> >
> > 2. I have the rig's power supply plugged into a relatively inexpensive
> > power strip, since I sometimes plug my laptop into it as well. Is there
a
> > higher-quality power strip that I might want to look at? Some have
> > suggested a power strip with something called a power isolator in it,
but
> > I'm not quite sure what it is.
> >
> > Please give me your feedback on both of these possible suggested
> > solutions.
> > Or, if you have any other suggestions, please send them to me.
> >
> > Some have suggested trying to put a capacitor across the leads of the
> > trailer's thermostat unit, but I really am hesitant to do that, at the
> > risk
> > of somehow voiding the warranty on the temperature control system.
> >
> > Thanks for anything you can suggest.
> >
> > 73 from Tom Behler: KB8TYJ, Big Rapids, MI
> >
> >
> >
>
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