Re: [AMRadio] 160 meter antenna

Mon, 12 Jan 2009 12:36:06 -0800

Bill, I wasn't aware the broadcast towers were sitting atop of a insulator on the base...is this considered the norm? What type of material would you suppose the insulator is made with?
-------------- Original message from BILL GUYGER <[email protected]>: --------------

This is a skirt type antenna it's a fairly common "trick" used at some AM b'cast sites. This way the tower can be grounded rather than sitting on a base
> insulator.
>
> Bill AD5OL
>
>
>
>
> ________________________________
> From: "[email protected]" To: [email protected]; Discussion of AM Radio in the Amateur Service
>
> Sent: Monday, January 12, 2009 12:13:42 PM
> Subject: Re: [AMRadio] 160 meter antenna
>
> Hello Jack. I am familiar with the lynards that the climbers use as a safety line while climbing the tower. Their are however 3 vertical lines made out of what looks like guy wire with a circular ring near the base being fed by a box
> at the base. Just a FYI -------------- Original message from "JACK C. SHUTT" :
> --------------
>
>
> Hi Robert,
> We have several of those wireless towers and monopoles around here, as well  Those side wires are safety cables that climbers can clip on to with
> fall-arresting lanyards and harnesses, they are not radiators. 
> Anyway, the folded unipole is a worthwhile antenna to try.  I have had excellent
> results with an inverted L running up the side of my 80' tower and the
> "horizontal" portion sloping out to a tree.  The "L' perhaps looks more like a
> vee with one short leg.  Total length is about 135 ft.  I use a coil and
> capacitor parallel network at the base of the tower feeding the end of the
> antenna wire then coax back to the shack.  As always, a good radial system
> really helps.
>
> 73,  Jack, W9GT
>
> --- On Mon, 1/12/09, [email protected] wrote:
>
> From: [email protected]
> Subject: Re: [AMRadio] 160 meter antenna
> To: [email protected], "Discussion of AM Radio in the Amateur Service"
>
> Date: Monday, January 12, 2009, 7:23 AM
>
>
> Neal. Thanks for the link on building the Unipole. I had worked for Sprint for
> some time and I noticed they were using that same concept on many of their
> towers. The link was exceptionally helpful
> -------------- Original message from neal Newman :
> --------------
>
>
> > Jim you only need 50 feet of verticle space.
> > why not just build yourself a Folded Unipole antenna if you Dont know how.
> Ask. its really easy. Just Run 3 lengths of #12 wire or if you have it #6 wire.
> short them up at around the 50 foot point and use 1" PVC
> > Tubing as Insulators with clamps Down the side of the Tower.
> > at the bottom Each wire is isolated with PVC from the Tower.
> > BTW Each wire should be about 12" or more off the tower. then Tie all 3 wires
> together with a ring of #12 and take that as the Lead to the antenna tuner. Run
> at Least 4 ground radials 50 feet long If you can get
> > the space make them 120 feet...
> > and you will have a Killer 160 antenna. if not make an inverted L Run a wire
> thats 130 feet long. as far vertically as
> > you can then run the rest out horizontally... again you need at least 4 ground
> radials.... the unipole is what we use for
> > Broadcast stations when we are tight for height or space on a grounded Tower.
> >
> > Neal-KA2CAF
> > CE- WTTM/WHWH/WJDM/WIBG/WFYL
> >
> >
> > --- On Sun, 1/11/09, Jim Miller WB5OXQ in Waco wrote:
> >
> > > From: Jim Miller WB5OXQ in Waco
> > > Subject: [AMRadio] 160 meter antenna
> > > To: "Discussion of AM Radio in the Amateur Service"
> > > Date: Sunday, January 11, 2009, 11:28 PM
> > > I always wanted to try am on 160 but like most do not have
> > > enough room for a full size antenna, so,
> > > I am considering building a 160 meter antenna at our
> > > clubhouse because there is a 80' tower there and over an
> > > acre of land to spread out a 1/2 wave dipole. Question is;
> > > 1 Is a 1/2 wave wire dipole the best antenna for the band
> > > considering there is room for it.
> > > 2 Is 80' high enough for the center of the inverted V?
> > > 3 How high do the ends need to be off of the ground?
> > > 4 Should I feed it with coax or ladder line to the 10'
> > > level (or other) then a balun to coax to the tuner (coax is
> > > the only acceptable line into the shack)? The shack is a
> > > metal building 30X60' and directly below the tower.
> > > There is no way to get ladder line to the operating position
> > > since all cables have to run through a 3" conduit for
> > > at least 30'.
> > >
> > > The tower is a free standing commercial tower made of 4
> > > 20' sections bolted together with a 2 meter and a 440mhz
> > > antenna at the top, all ham antennas.
> > >
> > > Thanks for any advice. Jim
> > > wb5oxq______________________________________________________________
> > > Our Main Website: http://www.amfone.net
> > > AMRadio mailing list
> > > Searchable Archives:
> > > http://www.mail-archive.com/[email protected]/
> > > List Rules (must read!): http://w5ami.net/amradiofaq.html
> > > List Home: http://mailman.qth.net/mailman/listinfo/amradio
> > > Help: http://mailman.qth.net/mmfaq.html
> > > Post: mailto:[email protected]
> > > To unsubscribe, send an email to
> > > [email protected] with
> > > the word unsubscribe in the message body.
> >
> >
> >
> > ______________________________________________________________
> > Our Main Website: http://www.amfone.net
> > AMRadio mailing list
> > Searchable Archives: http://www.mail-archive.com/[email protected]/
> > List Rules (must read!): http://w5ami.net/amradiofaq.html
> > List Home: http://mailman.qth.net/mailman/listinfo/amradio
> > Help: http://mailman.qth.net/mmfaq.html
> > Post: mailto:[email protected]
> > To unsubscribe, send an email to [email protected] with
> > the word unsubscribe in the message body.
> ______________________________________________________________
> Our Main Website: http://www.amfone.net
> AMRadio mailing list
> Searchable Archives: http://www.mail-archive.com/[email protected]/
> List Rules (must read!): http://w5ami.net/amradiofaq.html
> List Home: http://mailman.qth.net/mailman/listinfo/amradio
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:[email protected]
> To unsubscribe, send an email to [email protected] with
> the word unsubscribe in the message body.
> ______________________________________________________________
> Our Main Website: http://www.amfone.net
> AMRadio mailing list
> Searchable Archives: http://www.mail-archive.com/[email protected]/
> List Rules (must read!): http://w5ami.net/amradiofaq.html
> List Home: http://mailman.qth.net/mailman/listinfo/amradio
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:[email protected]
> To unsubscribe, send an email to [email protected] with
> the word unsubscribe in the message body. 
______________________________________________________________
Our Main Website: http://www.amfone.net
AMRadio mailing list
Searchable Archives: http://www.mail-archive.com/[email protected]/
List Rules (must read!): http://w5ami.net/amradiofaq.html
List Home: http://mailman.qth.net/mailman/listinfo/amradio
Help: http://mailman.qth.net/mmfaq.html
Post: mailto:[email protected]
To unsubscribe, send an email to [email protected] with
the word unsubscribe in the message body.

Reply via email to