I've heard it said in the past that 10 isn't big enough wire for a really
good RF ground, not sure I believe it,b ut thought I'd mention it.
----- Original Message -----
From: "T Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, July 28, 2006 6:03 PM
Subject: Re: continuing RFI problems in travel trailer
> Steve:
>
> Thanks for the clarifications.
>
> The ground wire that runs to the ground rod is no more than about 6 feet
> long. It goes from the rig, through a hole in the floor of the trailer,
> and
> outside to the grounding rod.
>
> I purposely kept it as short as possible.
>
> Just for additional information, the ground wire I'm using is 10'gauge
> insulated braded wire purchased from the local hardware store.
>
> 73 from Tom Behler: KB8TYJ
>
>
>
> ----- Original Message -----
> From: "Steve Forst" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, July 28, 2006 3:38 PM
> Subject: Re: continuing RFI problems in travel trailer
>
>
>> Tom,
>> Yes, a little over 16 feet. 234 / freq in mhz
>>
>> It acts as a counterpoise, so other end isn't attached to anything.
> Not
>> sure how big the trailer is and if you can get it out in a roughley
>> straight line or not. Maybe you can run it outside somehow. Wire size
>> isn't too important, 14, 16, 18 whatever you have.. Put a piece of tape
> on
>> the other end, it will be hot when you tx. May make things worse, but
> worth
>> a try.
>>
>> How long is the ground wire that runs to the ground rod?
>>
>> Steve KW3A the
>>
>>
>> ----- Original Message -----
>> From: "T Behler" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Friday, July 28, 2006 3:08 PM
>> Subject: Re: continuing RFI problems in travel trailer
>>
>>
>> > 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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