Rod and all the other Nice guys that answer the
question, after reading and see my chances, will try
to adjust a littl higher in the 50.100s when wet the
antena will be in a good range of SWR.
Many thanks guys for your Help
Hector XE2K
--- Sadtip <sad.tip@verizon.net> wrote:
> Sorry to all about the link. I normally check my
> links before sending them
> but I forgot to this time.
>
> It's under the "support" tab and then click on
> "water and rain testing"
>
>
> 73's and thanks for the correction.
>
> RoD
> KD0XX
>
> A good friend will come and bail you out of jail,
> A TRUE friend will be sitting next to you
> saying.....
>
>
> "DAMN THAT WAS FUN"
>
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com
> > [mailto:towertalk-bounces@contesting.com]On Behalf
> Of Steve Katz
> > Sent: Friday, July 27, 2007 6:00 PM
> > To: sad.tip@verizon.net; Hector@xe2k.net; Tower
> Talk
> > Subject: Re: [TowerTalk] m2 6M7 SWR change with
> rain
> >
> >
> > That M2 link just takes you to the main website,
> not specifically to
> > anything about rain and 6m beams. I took the
> liberty of copying
> > just a few
> > sentences on this specific subject (pasted from M2
> website
> > directly, credit
> > to them!):
> >
> > "CLEARLY THE CAUSE OF ANY SHIFT IS BECAUSE THE
> ANTENNA IS A CRITICALLY
> > TUNED, HIGH GAIN YAGI WITH A VERY LOW FEED
> IMPEDANCE. THE GAIN
> > CURVE IN THIS
> > DESIGN PEAKS BETWEEN 50.200 AND 50.300 BUT IS ONLY
> DOWN .06 DB AT
> > 50.000 AND
> > 50.400 MHZ SO EVEN IF ALL THE WORKING PARAMETERS
> OF THE ANTENNA
> > SHIFTED DOWN
> > 200 KHZ, YOUR GAIN WOULD ONLY DROP BY .06 DB. AT
> 50.1 MHZ.
> >
> > THE MOST TOUCHY SECTION IS CLEARLY THE DRIVEN
> ELEMENT TIPS. ANY DIELECTRIC
> > NEAR OR ON THE TIP OF THE ELEMENT WILL DRIVE THE
> FREQUENCY
> > DOWNWARD. EVEN A
> > PLASTIC CAP OVER THE END WILL HAVE THAT EFFECT.
> WATER IS A DIELECTRIC. THE
> > RAIN OR WATER DROPS ALSO INCREASE THE DIAMETER OF
> THE ELEMENT MAKING IT GO
> > EVEN LOWER IN FREQUENCY. IF THE DIAMETER OF THE
> DRIVEN ELEMENT
> > WERE LARGER,
> > WATER WOULD HAVE LESS EFFECT. WIND AREA AND COST
> WOULD GO UP
> > UNFORTUNATELY.
> > ENGINEERING WILL LOOK INTO JUST INCREASING THE
> EFFECTIVE TIP
> > DIAMETER OF THE
> > DRIVEN ELEMENT TO REDUCE THIS EFFECT. RESULTS OF
> THESE TEST WILL BE
> > ANNOUNCED FOR THOSE OF YOU WHO NEED HELP IN THIS
> AREA."
> >
> > This is exactly what I said it was...rain droplets
> on the element tips.
> > When the wind blows them off or the sun dries them
> out, everything returns
> > to normal. This is normal behavior for a
> narrowband yagi
> > antenna, from what
> > I've seen, they all do it.
> >
> > -WB2WIK/6
> >
> >
> >
> > -----Original Message-----
> > From: Sadtip [mailto:sad.tip@verizon.net]
> > Sent: Friday, July 27, 2007 2:57 PM
> > To: Hector@xe2k.net; Tower Talk
> > Subject: Re: [TowerTalk] m2 6M7 SWR change with
> rain
> >
> > Hector,
> > M2 put together a pretty complete description and
> explanation of the
> > problem at....
> >
> > http://www.m2inc.com/index2.html
> >
> > They used a 6M5X but it's still worth a read and
> might help.
> >
> > 73's
> > RoD
> > KD0XX
> >
> > A good friend will come and bail you out of jail,
> > A TRUE friend will be sitting next to you
> saying.....
> >
> >
> > "DAMN THAT WAS FUN"
> >
> > > -----Original Message-----
> > > From: towertalk-bounces@contesting.com
> > > [mailto:towertalk-bounces@contesting.com]On
> Behalf Of Hector Garcia XE2K
> > > Sent: Friday, July 27, 2007 4:42 PM
> > > To: Tower Talk
> > > Subject: [TowerTalk] m2 6M7 SWR change with rain
> > >
> > >
> > > Hi guys:
> > >
> > > A friend just install the 6M7 in his office
> tower
> > > and he report that his antena in the last rains
> the
> > > swr change from the perfect 50.125 1:1 to 49.9
> 1:1
> > > when the antena is WET , just dry and the SWR
> back to
> > > 50.125
> > >
> > > I have a 6M7JHV in the box to be installed at
> 150ft
> > > and really i will like to know if adding some
> clear
> > > spray or paint to the driven will reduce or
> eliminate
> > > that problem of SWR change when WET.
> > >
> > > any solve the problem ? any solution avaliable
> > >
> > > or just live with that ?
> > >
> > >
> > > Hector
> > >
> > > Hector Garcia XE2K / XF1K
> > > Mexicali B.C DM22fp
> > > P.O.Box 73
> > > El Centro CA 92244-0073
> > > USA
> > > http:// www.xe2k.net
> > > http://www.dxxe.org
> > > _______________________________________________
> > >
> > >
> > >
> > > _______________________________________________
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > >
>
http://lists.contesting.com/mailman/listinfo/towertalk
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> >
>
http://lists.contesting.com/mailman/listinfo/towertalk
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> >
>
http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
>
http://lists.contesting.com/mailman/listinfo/towertalk
>
Hector Garcia XE2K / XF1K
Mexicali B.C DM22fp
P.O.Box 73
El Centro CA 92244-0073
USA
http:// www.xe2k.net
http://www.dxxe.org
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