Henny!
Just take a look at: http://www.dx-wire.de/brit/
To support a small probe or a vertical wire the cheapest 10m pole is
suitable and I think the price is really o.K.
For my LF-Antenna with the top-loads I use other types of masts (one 12m
and one 18m) available at:
http://spiderbeam.com/home/index.php?language=en
They are more expensive but really "heavy duty".
73
OE3GHB
Gerhard
Am Sonntag, den 14.08.2011, 11:27 +0200 schrieb henny van elst:
> Hello Gerhard,
> can You give me the addres to order a fiberglasmast?
>
> henny pa3cpm
> best 73's
>
> ----- Original Message -----
> From: "Gerhard Hickl" <[email protected]>
> To: <[email protected]>
> Sent: Thursday, August 11, 2011 9:14 PM
> Subject: Re: LF: Re: HB9ASB...
>
>
> > John!
> >
> > Actually there is no special guying used since the mast is only the
> > lower (and thus thicker) section of an originally 10m high "cheap"
> > Fibreglass-Pole like available at http://www.dx-wire.de/fiberglasm.htm
> >
> > It is tied to the chimney with two tension belts which are commonly used
> > to fix cargo in a truck. (1 inch wide).
> >
> > Originally this method of fixing to the chimney was just thought to be
> > for testing but meanwhile it is up there for more than a year.
> >
> > The two probes (LF/VLF) on top of the mast are suspended by a string
> > which enables me to maintain the probes without bringing the pole down.
> >
> > 73
> > OE3GHB
> > Gerhard
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Am Donnerstag, den 11.08.2011, 17:58 +0200 schrieb John Rabson:
> >> Gerhard,
> >>
> >> What guying arrangements do you use for the 5m mast, please?
> >>
> >> 73
> >> John F5VLF
> >>
> >> On 11 Aug 2011, at 16:59CEST, Gerhard Hickl wrote:
> >>
> >> > Clemens, LF group!
> >> >
> >> > This is exactly the opposite that I experienced with the Mini-Whip.
> >> >
> >> > The higher I brought it up (= the farther I brought it away from the
> >> > noise source, commonly called "house"), the better the SNR.
> >> >
> >> > Today I connected the shield of the cable to the lightning protection
> >> > system up on the roof and couldn't find any difference so far.
> >> >
> >> > I'm using a 5m fibre-glass pole fixed to the chimney as a support for
> >> > the probe and the shield of the feeder is only grounded in the shack.
> >> >
> >> > 73
> >> >
> >> > OE3GHB
> >> > Gerhard
> >> >
> >> >
> >> >
> >> >
> >> >
> >> > Am Donnerstag, den 11.08.2011, 13:32 +0200 schrieb Clemens Paul:
> >> >> Hi Stefan,
> >> >>
> >> >>> The pole that is on a noisy roof (and its noisy ground) and on the
> >> >>> other side
> >> >>> the pole that is far away in the garden, with its own and clean local
> >> >>> earth.
> >> >>> In the garden a metallic pole should make no difference, as you say.
> >> >>
> >> >> How true.
> >> >> My miniwhip was completely unusable on the top of my roof,
> >> >> with or without connecting the coax shield to the lightning
> >> >> gr.. ehm reference plane.
> >> >> So I decided to put it in the middle of thegarden where it is only
> >> >> 30cm
> >> >> above the lawn.
> >> >> Here connecting the coax braid to a 3m long earth rod was essential
> >> >> to get rid of the noise.
> >> >> Now this setup is good enough for receiving SAQ with up to 30dB S/N.
> >> >>
> >> >> 73
> >> >> Clemens
> >> >> DL4RAJ
> >> >>
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> ----- Original Message -----
> >> >> From: "Stefan Schäfer" <[email protected]>
> >> >> To: <[email protected]>
> >> >> Sent: Thursday, August 11, 2011 9:58 AM
> >> >> Subject: Re: LF: Re: HB9ASB...
> >> >>
> >> >>
> >> >>> Hi Gerhard,
> >> >>>
> >> >>> I think one has to compare two different situations:
> >> >>>
> >> >>> The pole that is on a noisy roof (and its noisy ground) and on the
> >> >>> other side
> >> >>> the pole that is far away in the garden, with its own and clean local
> >> >>> earth.
> >> >>> In the garden a metallic pole should make no difference, as you say.
> >> >>>
> >> >>> 73, Stefan
> >> >>>
> >> >>>
> >> >>> Am 11.08.2011 05:33, schrieb Gerhard Hickl:
> >> >>>> Roelof!
> >> >>>>
> >> >>>> With interest I was following all the discussions about the "Mini
> >> >>>> Whip"-like antennas.
> >> >>>>
> >> >>>> In your description of the "PA0RDT Mini Whip" you suggest to use a
> >> >>>> non
> >> >>>> metallic pole for mounting the probe and an (optional) earth-rod to
> >> >>>> ground (sorry Andy!!) the shield.
> >> >>>>
> >> >>>> I might be completely wrong but isn't it the same when one uses a
> >> >>>> grounded metallic pole and connect the shield of the coax on top of
> >> >>>> this
> >> >>>> pole?
> >> >>>>
> >> >>>> BTW: I have an insulating pole (5m) on top of the roof and yet no
> >> >>>> grounded shielding of the coax but just in the shack. I will connect
> >> >>>> the
> >> >>>> shield to the lightning protection system at the bottom of the pole
> >> >>>> and
> >> >>>> see about the difference.
> >> >>>>
> >> >>>> Actually it isn't even a true coax cable but a singe shielded
> >> >>>> twisted
> >> >>>> pair where the two inner wires are in parallel....Z=? Who knows????
> >> >>>>
> >> >>>> So considering my "fluffy" set-up, I think my VLF grabber is
> >> >>>> performing
> >> >>>> very well but for sure there is room for improvements as well.
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>> 73
> >> >>>> OE3GHB
> >> >>>> Gerhard
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>>
> >> >>>> Am Mittwoch, den 10.08.2011, 21:26 +0200 schrieb Roelof Bakker:
> >> >>>>
> >> >>>>> Hello Minto, Stefan,
> >> >>>>>
> >> >>>>> Some food for thoughts:
> >> >>>>>
> >> >>>>> When I tested a mini-whip in the garden with battery feed and also
> >> >>>>> with a
> >> >>>>> battery fed SLM, I found the noise lower than when used inside and
> >> >>>>> operated from the mains.
> >> >>>>>
> >> >>>>> The coax cable from the house station was connected in parallel
> >> >>>>> with the
> >> >>>>> mini-whip by means of a BNC T-piece.
> >> >>>>> The noise increased by 9 dB. My assumption is that this noise is
> >> >>>>> received
> >> >>>>> on the shield of the coax inside the house.
> >> >>>>>
> >> >>>>> Without connecting the shield to a separate radio earth, the noise
> >> >>>>> received on the shield inside the house will travel over the shield
> >> >>>>> all
> >> >>>>> the way to the antenna. There the noise will be received by the
> >> >>>>> sensitive
> >> >>>>> probe. This will be by means of capacitively coupling, I guess.
> >> >>>>> Many
> >> >>>>> people have reported a large drop in local noise by connecting the
> >> >>>>> shield
> >> >>>>> at the bottom of the mast.
> >> >>>>> This also applies to normal active whips of course.
> >> >>>>>
> >> >>>>> 73,
> >> >>>>> Roelof, pa0rdt
> >> >>>>>
> >> >>>>>
> >> >>>>
> >> >>>>
> >> >>>
> >> >>>
> >> >>>
> >> >>> -----
> >> >>> eMail ist virenfrei.
> >> >>> Von AVG überprüft - www.avg.de
> >> >>> Version: 10.0.1392 / Virendatenbank: 1520/3826 - Ausgabedatum:
> >> >>> 10.08.2011
> >> >>
> >> >>
> >> >
> >> >
> >> >
> >> >
> >>
> >>
> >
> >
> >
> >
> >
> > -----
> > Geen virus gevonden in dit bericht.
> > Gecontroleerd door AVG - www.avg.com
> > Versie: 10.0.1392 / Virusdatabase: 1520/3827 - datum van uitgifte:
> > 08/11/11
> >
>
>
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