I'm with you there, I'd really recheck all coaxes, all connections, move
things around while checking them, see if there's something somewhere that
shorts under certain conditions. Close proximity to metal shouldn't measure
a CD short, it won't work with RF very well, don't I know that, but it
shouldn't measure a short.
----- Original Message -----
From: "Pat Byrne" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, August 21, 2012 8:02 AM
Subject: Re: G5RV Update
> But if Tom took the reading with the coax disconnected, he wouldn't
> be connected to the R V ground so shouldn't have seen the results he
> saw. And for the life of me I don't understand how mere proximity
> could cause a direct D C short.
> Puzzling.
> PatAt 05:24 AM 8/21/2012, you wrote:
>>Tom,
>>
>>If all the components of the G5 are insulated, I don't see how the antenna
>>being in the proximity of the metal roof or one of the legs wrapped around
>>a
>>metal ladder leg could cause continuity between the two sides of the
>>antenna. I do believe that the antenna wrapped around the ladder leg
>>would
>>most definitely detune it though.
>>
>>Now, if the ladder is connected to ground, perhaps through the metal frame
>>of the R V and the AC power system, and your G5 was actually connected to
>>the ladder through a break in the insulation on the antenna wire and the
>>shield side of your coax wiring in your RV is connected to that same power
>>line ground than you could read a possible short if the ladder side of
>>your
>>G5 was the center of the coax feed line.
>>
>>I don't know anything about RV construction, however if the AC receptacles
>>are mounted in metal electrical boxes and the electrical boxes are mounted
>>to a metal RV frame then the whole metal frame of the RV would be
>>connected
>>to the power line ground because the mounting ears of normal household
>>type
>>receptacles are connected to ground.
>>
>>I know that was poorly written, but read it slowly and I think you will
>>understand my thoughts.
>>
>>73
>>
>>Howard #3
>>
>>
>>
>>
>>
>>----- Original Message -----
>>From: "Tom Behler" <[log in to unmask]>
>>To: <[log in to unmask]>
>>Sent: Tuesday, August 21, 2012 4:42 AM
>>Subject: Re: G5RV Update
>>
>>
>> > Great suggestion, Howard, and I will definitely carry it out.
>> >
>> > Thanks very much.
>> >
>> > Tom Behler: KB8TYJ
>> >
>> > ----- Original Message -----
>> > From: "Howard, W A 9 Y B W" <[log in to unmask]>
>> > To: <[log in to unmask]>
>> > Sent: Monday, August 20, 2012 9:54 PM
>> > Subject: Re: G5RV Update
>> >
>> >
>> >> Tom,
>> >>
>> >> While you have the antenna down, do the following:
>> >>
>> >> 1. Check for continuity from the center pin of the coax connector on
>> >> the
>> >> coax pigtail to each end of the antenna's horizontal elements there
>> >> should
>> >> be continuity to one of them.
>> >>
>> >> 2. Now do the same from the shield side of the coax connector on the
>> >> coax
>> >> pigtail and you should have continuity to the end of the opposite leg.
>> >>
>> >> Alternatively, you could connect the ends of the antenna horizontal
>> >> legs
>> >> together if possible and than check for a short across the coax
>> >> connector
>> >> on
>> >> the end of the coax pigtail.
>> >>
>> >> I am only suggesting this so that you will know that there are no
>> >> breaks
>> >> in
>> >> the connections at each end of the ladder line. Can only do this on
>> >> the
>> >> ground. Impossible to do with the antenna in the air.
>> >>
>> >> 73
>> >>
>> >> Howard #3
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> ----- Original Message -----
>> >> From: "Tom Behler" <[log in to unmask]>
>> >> To: <[log in to unmask]>
>> >> Sent: Monday, August 20, 2012 8:05 PM
>> >> Subject: G5RV Update
>> >>
>> >>
>> >>> Hi, all.
>> >>>
>> >>> Well, tonight, with a little bribery in the form of an ice cream cone
>> >>> on
>> >>> the
>> >>> way out to the RV, the XYL and I took the trip to retrieve the
>> >>> suspect
>> >>> G5RV.
>> >>>
>> >>> The antenna is now right here in front of me, and guess what I found!
>> >>>
>> >>> With the antenna taken down, and now free of any connections, there
>> >>> is
>> >>> an
>> >>> open circuit across the PL259! In other words, no continuity across
>> >>> the
>> >>> connector!
>> >>>
>> >>> So, to me, this would indicate that the antenna is sound
>> >>> electrically.
>> >>>
>> >>> Before putting it up again, of course, I will check all connections,
>> >>> but
>> >>> this, to me, is very encouraging.
>> >>>
>> >>> It also indicates to me that there is a problem somewhere in my feed
>> >>> line
>> >>> system, hopefully not in the feed line that runs underneath the RV.
>> >>>
>> >>> At least, though, I think I've now got the problem isolated in a
>> >>> major
>> >>> way.
>> >>>
>> >>> Will keep everyone posted, but, unless I'm deluding myself, I'm now
>> >>> greatly
>> >>> encouraged.
>> >>>
>> >>> 73 from Tom Behler: KB8TYJ
>> >>
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