What is the Best Direction to 'Point' a Sloper Antenna for DX ?
RHF
Given an area where you could locate a Sloper Antenna
with a Tall Mounting Pole "Top-End-Feed-Point' and the
ability to move the Bottom-Far-End around the full circle
of 360 Degrees.
Where would you place 'Point' the Bottom-Far-End for the
best DXing ? [ N ? E ? W ? S ? ] & WHY ?
Given that it is claimed that in general the Sloper produces
it's best reception in the direction of the Bottom-Far-End.
Coax Cable to the Feed-Point and Top-End-Feed-Point.
Thinking of Rigging a Par Electronics EF-SWL Antenna
as a Sloper or buying one of these Pre-Make Slopers.
http://www.grove-ent.com/ANT8.html
Alpha Delta DX-SWL Sloper Antenna
http://www.universal-radio.com/catalog/sw_ant/0799.html
Eavesdropper Sloper Antenna
http://www.universal-radio.com/catalog/sw_ant/0013.html
i want to know ~ RHF
.
.
dave
> What is the Best Direction to 'Point' a Sloper Antenna for DX ?
>
> Given an area where you could locate a Sloper Antenna
> with a Tall Mounting Pole "Top-End-Feed-Point' and the
> ability to move the Bottom-Far-End around the full circle
> of 360 Degrees.
>
> Where would you place 'Point' the Bottom-Far-End for the
> best DXing ? [ N ? E ? W ? S ? ]& WHY ?
>
Top-fed slopers in an open space are essentially omnidirectional. Most
of the radiation happens at the feed point. The slantwire and the
support structure form a low Q mass that also radiates, equally well in
all directions.
bpnjensen
Dale P. has always recommended using his PAR end-fed as a sloper with
the feedpoint near the bottom and thus giving a nice short run to
ground. Good omni results and a high radiation angle. I think this
would work for me if I did not have such a battery of RFI generators
around my home.
Bruce
RHF
> On Aug 31, 7:11 am, dave <d...@dave.dave> wrote:
>
> > RHF wrote:
> > > What is the Best Direction to 'Point' a Sloper Antenna for DX ?
>
> > > Given an area where you could locate a Sloper Antenna
> > > with a Tall Mounting Pole "Top-End-Feed-Point' and the
> > > ability to move the Bottom-Far-End around the full circle
> > > of 360 Degrees.
>
> > > Where would you place 'Point' the Bottom-Far-End for the
> > > best DXing ? [ N ? E ? W ? S ? ]& WHY ?
>
> > Top-fed slopers in an open space are essentially omnidirectional. Most
> > of the radiation happens at the feed point. The slantwire and the
> > support structure form a low Q mass that also radiates, equally well in
> > all directions.
- Dale P. has always recommended using his PAR end-fed as a sloper
with
- the feedpoint near the bottom and thus giving a nice short run to
- ground. Good omni results and a high radiation angle. I think this
- would work for me if I did not have such a battery of RFI generators
- around my home.
-
- Bruce
BpnJ,
Now that is very Smart of Dale Par [W4OP]
http://www.eham.net/reviews/detail/3707
{Now... Why Didn't I Think of That !?!}
Plus -if- you run the Coax Cable directly underneath
the Antenna Wire; it would act as a Counterpoise
and a more uniform ground field.
- simplify - simplify - simplify -
Sort of the same approach that Wellbrook in the UK
recommends for a Far-End feed-point for a better
Inverted "L" Antenna.
http://www.wellbrook.uk.com/longwire.html
But that would eliminate the Tall rotational Center-Point
for directional testing : Which is OK since I am only
looking for the best single Direction be it N? E? W? S?
I guess that the SWL Sloper Antenna Designs by
both Alpha Delta and Eavesdropper were built around
using the Side of a House* as the High-Mounting-Point.
* Taking what the Customer already has and building
on that; to make the installation as simple and easy
as possible. {A No Brainer}
While most Amateur {Ham} Sloper Antennas generally
have a Bottom Feed-Point except for those attached
to an existing Tower/Mast.
BpnJ - tyvm for the tip ~ RHF
.
.
RHF
> > What is the Best Direction to 'Point' a Sloper Antenna for DX ?
>
> > Given an area where you could locate a Sloper Antenna
> > with a Tall Mounting Pole "Top-End-Feed-Point' and the
> > ability to move the Bottom-Far-End around the full circle
> > of 360 Degrees.
- - Where would you place 'Point' the
- - Bottom-Far-End for the best DXing ?
- - [ N ? E ? W ? S ? ] & WHY ?
- Top-fed slopers in an open space are essentially
- omnidirectional. Most of the radiation happens at
- the feed point. The slantwire and the support
- structure form a low Q mass that also radiates,
- equally well in all directions.
Dave - Tha is All very True for Transmitting Antennas
that are 'Radiating' Power from them; be it 1W, 10W,
100W, 1KW . . .
But a Receiving Antenna collecting 'free' Radiated
Power from the Either in the order of mW ~ nW :
The Direction {lay of the wire}; Ssize {length of the
wire}; and Position {angle of the wire} can each and
all contribute to the 'general direction' that the Wire
will gather 'more' RF Signals from : Given that some
RF Signals will be Radiating from a Point-Source
and mostly Traveling a specific Path between the
originating Point-Source and the specific Location
of the Receiving Antenna.
in search of the one-best answer . . . ~ RHF
[ N ? E ? W ? S ? ] & WHY ?
.
.
RHF
- - RHF wrote:
- - What is the Best Direction to 'Point' a Sloper Antenna for DX ?
> >Given an area where you could locate a Sloper Antenna
> >with a Tall Mounting Pole "Top-End-Feed-Point' and the
> >ability to move the Bottom-Far-End around the full circle
> >of 360 Degrees.
- - Where would you place 'Point' the Bottom-Far-End
- - for the best DXing ? [ N ? E ? W ? S ? ] & WHY ?
> >Given that it is claimed that in general the Sloper produces
> >it's best reception in the direction of the Bottom-Far-End.
>
> >Coax Cable to the Feed-Point and Top-End-Feed-Point.
>
> >Thinking of Rigging a Par Electronics EF-SWL Antenna
> >as a Sloper or buying one of these Pre-Make Slopers.
> >http://www.grove-ent.com/ANT8.html
>
> >Alpha Delta DX-SWL Sloper Antenna
> >http://www.universal-radio.com/catalog/sw_ant/0799.html
>
> >Eavesdropper Sloper Antenna
> >http://www.universal-radio.com/catalog/sw_ant/0013.html
>
> >i want to know ~ RHF
> > .
> > .
>
- If you've got the room to select a direction, why not have a series
of stakes at
- different points of azimuth and maybe a carabiner fastening setup so
the thing
- could be quickly changed depending on your preferred direction at
the time?
-
- --
-
- Operator Bob
- Echo Charlie 42
"OB",
Given that I am on the West Coast of the USA
Northern California Sierra Foothills.
1 - Receive Trans Pacific Shortwave strongly from
New Zealand & Australia & Singapore & China &
Japan & Russian Far-East
2 - Receive Shortwave from the East Coast of the
USA very good.
3 - Receive Shortwave from South {Latin} America good.
4 - Do NOT receive Shortwave from Europe well.
5 - Do NOT receive Shortwave from Middle-East
Region well at all.
6 - Do NOT receive Shortwave from Africa well.
7 - Do NOT receive Shortwave from India etc well.
What Diriection would you 'Point' the Bottom-End of
a Sloper Antenna for the best DXing from : Europe ?
Middle-East ? Africa ? and India ?
? N ? E ? W ? S ? and WHY ?
in search of the one-best answer . . . ~ RHF
.
.
RHF
> On Aug 31, 7:11 am, dave <d...@dave.dave> wrote:
>
> > RHF wrote:
> > > What is the Best Direction to 'Point' a Sloper Antenna for DX ?
>
> > > Given an area where you could locate a Sloper Antenna
> > > with a Tall Mounting Pole "Top-End-Feed-Point' and the
> > > ability to move the Bottom-Far-End around the full circle
> > > of 360 Degrees.
>
> - - Where would you place 'Point' the
> - - Bottom-Far-End for the best DXing ?
> - - [ N ? E ? W ? S ? ] & WHY ?
>
> - Top-fed slopers in an open space are essentially
> - omnidirectional. Most of the radiation happens at
> - the feed point. The slantwire and the support
> - structure form a low Q mass that also radiates,
> - equally well in all directions.
-correction- 'Tha' to "That" just for M II :o)
- Dave - That is All very True for Transmitting Antennas
- that are 'Radiating' Power from them; be it 1W, 10W,
- 100W, 1KW . . .
arthr...@webtv.net
>
> - Show quoted text -
Though I have not been living on the West coast, nevertheless one
cannot expect strong signals from certain areas over there . In
dealing with such unstable propagation as we had in the last few years
a single antenna may not be sufficient and re-orienting it may not be
enough. Over here,in NYC I tried using a commercially made sloper
antenna in the early 90's and didn't see it performing substantially
better than a simple random length wire. That applies only to my
location,that is. . . The best antenna I EVER had was a home-made
T2FD. Much quieter,had some gain and it was absolutely
omnidirectional as far as I know. It used a 9:1 balun transformer from
Palomar (sadly they stopped making it). Reception was
outstanding,considering the RFI and other man-made noise omnipresent
over here.
RHF
- nevertheless one cannot expect strong signals
- from certain areas over there . In dealing with
- such unstable propagation as we had in the last
- few years a single antenna may not be sufficient
- and re-orienting it may not be enough.
- Over here,in NYC I tried using a commercially made
- sloper antenna in the early 90's and didn't see it
- performing substantially better than a simple
- random length wire. That applies only to my
- location,that is. . .
- The best antenna I EVER had was a home-made
- T2FD. Much quieter,had some gain and it was
- absolutely omnidirectional as far as I know.
T2FD : Terminated Tilted Folded Dipole Shortwave Antenna
http://www.johncon.com/john/T2fd/
- It used a 9:1 balun transformer from Palomar
- (sadly they stopped making it).
-fyi- The Palomar Engineers "MLB-1" Magnetic
Longwire Balun for Shortwave {Radio} Listening
Antennas is still being made. ~$50US
http://www.palomar-engineers.com/MLB-1/mlb-1.html
- Reception was outstanding,considering the RFI
- and other man-made noise omnipresent over here.
Several years ago I bought a used Wellbrook [UK]
Universal Magnetic Balun UMB T2FD and never
http://www.wellbrook.uk.com/UMBT2FD.html
got around to using it. IIRC it is somewhere down
in sub-basement # 3 -but- like I bought it and
stuck it on a shelf and don't think that I have seen
it in years. Heck I have not been down to check
out sub-basement # 3 in years . . . hope that the
sump pumps are still working . . . got to add that
to my To-Do List on the next trip to Alameda, CA.
I already have two SWL Antennas up here in
Twain Harte, CA -but- neither seems bring in
Europe; the Middle-East; Africa and India.
.
* Inverted "L" Antenna with a Ground Rod
mounted WinRadio WR-LWA-0130 Long
Wire Adapter Matching Transformer; and
Coax Cable feed-in-line.
Antenna Element : 26 Foot Vertical-Up-Leg
-by- 103 Foot Horizontal-Out-Arm with the
Far-End pointed at 275 Degrees.
.
* Horizontal Antenna 100 Foot make-up of a
5-Wire Rotar Cable with each Wire "cut-to'
a Shortwave Radio Band :
http://www.google.com/group/rec.radio.shortwave/msg/aea23fa41d6f5241
1 @ 98 Feet ~ 120m SW Band
2 @ 71 Feet ~ 90m SW Band
3 @ 59 Feet ~ 75m SW Band
4 @ 48 Feet ~ 60m SW Band
5 @ 39 Feet ~ 49m SW Band
using an RF Systems MLB with Far-End
pointed at 30 Degrees and Ground into a
RG6/UQ Feed-in-Line
The Sloper Antenna would be SWL Antenna # 3
and pointed in the one best direction to consistantly
and reliably Receive [DX] : Europe; the Middle-East;
Africa and India. -if- that is possible . . .
? N ? E ? W ? S ? and WHY ?
pal ~ RHF
.
.
Kevin Alfred Strom
I don't know if the original claim of omnidirectionality is true or
false.
But I do know that a given antenna's pattern doesn't change between
receive and transmit.
The best way to determine the pattern of an antenna, short of
actually measuring it on an antenna range, is to model it on your
computer. Eznec does a great job of this (don't forget to enter an
appropriately lossy ground emulation for your location) and the demo
version is free.
73,
Kevin, WB4AIO.
--
http://kevinalfredstrom.com/
dave
it works so good. The current max is 40 feet in the air.
dave
>
> Dave - Tha is All very True for Transmitting Antennas
> that are 'Radiating' Power from them; be it 1W, 10W,
> 100W, 1KW . . .
>
Reciprocity says that the same rules apply to receiving.
Here's the listen only version of the Alpha Delta. It is top fed for
best performance as well.
dave
>
> What Diriection would you 'Point' the Bottom-End of
> a Sloper Antenna for the best DXing from : Europe ?
> Middle-East ? Africa ? and India ?
>
> ? N ? E ? W ? S ? and WHY ?
>
> in search of the one-best answer . . . ~ RHF
> .
> .
Have you generated a Great Circle map centered on your location? That
would be step one.
Just Plain Burr
"dave" <da...@dave.dave> wrote in message
news:4c7cff85$0$5509$bd46...@news.dslextreme.com...
I use a sloper "L".
The long leg is North/South and the short leg is high and East/West.
Seems to work fine for me.
I also have a right angle eve antenna, 20 foot per leg.
Burr
bpnjensen
> I already have two SWL Antennas up here in
> Twain Harte, CA -but- neither seems bring in
> Europe; the Middle-East; Africa and India.
That's why they call it DX, I guess! Our California location simply
is not at anybody's target area, and only occasionally off the
backside of the beam. If we were in someone's sights, or if we had
that extra bit of ocean between us and them, we'd probably hear them
better.
Also, most of the European stations either totally ignore NA or else
use relays to get their point across, resulting in service only from
other locations. The ones that still use their native soils for
transmitting to us - Czechia, Romania, Albania - all manage fairly
well some of the time.
India is especially absent from California airwaves. Don't know why,
exactly.
Bruce Jensen
bpnjensen
>
> - Show quoted text -
How do you suspend the top?
dxAce
bpnjensen wrote:
Not certain, but I think Ron Howard out of San Diego, or the Asilimar Beach
(sp) area has some spectacular reception of the Indian stations at or just
after sunrise there.
>
>
> Bruce Jensen
bpnjensen
Yes, he gets to Asilomar SB and reels out his portable antenna away
from the RFI - and reels the stations in. Oh, to be retired!
Around here, though, those lower HF bands are exceedingly noisy and
dead.
dxAce
bpnjensen wrote:
Sorry for your noise, as I'm still working on a bit of an issue here myself.
But I'm still amazed that at times I can hear Radio Fly, PNG, on 5960 at times
even an hour after my local sunrise.
bpnjensen
>
> - Show quoted text -
I hear Fly, but only a carrier with *weak* modulation, at any time.
I may have to break down and try a Wellbrook. If that does not work,
I'm out of ideas.
Hope your noise issue is resolved rapidamente!
RHF
> On Sep 1, 3:44 am, RHF <rhf-newsgro...@pacbell.net> wrote:
>
> > I already have two SWL Antennas up here in
> > Twain Harte, CA -but- neither seems bring in
> > Europe; the Middle-East; Africa and India.
>
> That's why they call it DX, I guess! Our California location simply
> is not at anybody's target area, and only occasionally off the
> backside of the beam. If we were in someone's sights, or if we had
> that extra bit of ocean between us and them, we'd probably hear them
> better.
>
> Also, most of the European stations either totally ignore NA or else
> use relays to get their point across, resulting in service only from
> other locations. The ones that still use their native soils for
> transmitting to us - Czechia, Romania, Albania - all manage fairly
> well some of the time.
- India is especially absent from California airwaves.
- Don't know why, exactly.
-
- Bruce Jensen
Hey is Bollywood is Anti-Hollywood ;;-}} ~ RHF
.
RHF
- I have an Alpha Delta DX-B half sloper.
- It feeds at the top.
- That's why it works so good.
- The current max is 40 feet in the air.
Alpha Delta "DX-B" 1/4-Wave Sloper Antenna
for 160-80-40-30 Metres
http://www.alphadeltacom.com/dxb_i.htm
http://www.alphadeltacom.com/qw_slopers.html
http://www.alphadeltacom.com/pdf/DX-A-%20DX-B_instructions.pdf
.
RHF
> > On Sep 1, 3:44 am, RHF <rhf-newsgro...@pacbell.net> wrote:
>
> > > I already have two SWL Antennas up here in
> > > Twain Harte, CA -but- neither seems bring in
> > > Europe; the Middle-East; Africa and India.
>
> > That's why they call it DX, I guess! Our California location simply
> > is not at anybody's target area, and only occasionally off the
> > backside of the beam. If we were in someone's sights, or if we had
> > that extra bit of ocean between us and them, we'd probably hear them
> > better.
>
> > Also, most of the European stations either totally ignore NA or else
> > use relays to get their point across, resulting in service only from
> > other locations. The ones that still use their native soils for
> > transmitting to us - Czechia, Romania, Albania - all manage fairly
> > well some of the time.
>
> > India is especially absent from California airwaves. Don't know why,
> > exactly.
- Not certain, but I think Ron Howard out of
- San Diego, or the Asilimar Beach (sp) area
- has some spectacular reception of the
- Indian stations at or just after sunrise there.
It appears that : Ron Howard using an Eton E1
portable AM/FM Shortwave Radio is most often
http://dxersguide.blogspot.com/
http://dxasia.info/uadx/UADX149.pdf
http://www.dswci.org/try/dxw/dxw400.pdf
listed as Asilomar State Beach, CA, USA
http://en.wikipedia.org/wiki/Asilomar_State_Beach
in the Monterey Bay Area of the Central
California Coast; a very nice area.
>
>
> > Bruce Jensen
RHF
BpnJ have you looked at the K9AY Loop Antenna ?
developed in the early 1990's by Gary Breed [K9AY]
http://www.hard-core-dx.com/nordicdx/antenna/loop/k9ay/
http://home.comcast.net/~markwa1ion/exaol1/k9ay_ant.htm
http://www.hard-core-dx.com/nordicdx/antenna/loop/k9ay/k9ay_ant.gif
http://www.arraysolutions.com/Products/lowbandrcv.htm
* Impressions and a field test K9AY Loop Antenna
-by- Bjarne Mjelde
http://www.dxing.info/equipment/k9ay.dx
-or- The Larger Wellbrook 'Thin Wire' Loop Antenna ?
Wellbrook Large Aperture "ALA100" Loop Antenna
http://www.wellbrook.uk.com/pdf/ALA100B1.pdf
http://www.wellbrook.uk.com/antennashop/image/cache/laloop-500x500.jpg
http://www.wellbrook.uk.com/antennashop/index.php?route=product/product&path=35&product_id=35
* Active Loop Antenna ALA100M Large/Medium Aperture
http://www.wellbrook.uk.com/pdf/ALA100Ma.pdf
http://www.wellbrook.uk.com/antennashop/index.php?route=product/product&path=35&product_id=48
something to think {dream} about ~ RHF
.
dxAce
bpnjensen wrote:
I wasn't aware that he hits the beach as I thought he lived there.
That has to be pretty darn cool to be able to do that.
dave
Antipodal?
dave
50' telescoping mast and lots of Dacron
bpnjensen
Maybe - but I get other such stations fairly regularly - RN/VOA
Madagascar, BBC Seychelles, Sri Lanka...?
bpnjensen
I like it! :-)
RHF
> RHF wrote:
>
> > Dave - Tha is All very True for Transmitting Antennas
> > that are 'Radiating' Power from them; be it 1W, 10W,
> > 100W, 1KW . . .
>
> Reciprocity says that the same rules apply to receiving.
>
- It is top fed for best performance as well.
-
- http://www.alphadeltacom.com/dxswlii.htm
I guess that the SWL Sloper Antenna Designs by
both Alpha Delta and Eavesdropper were built around
using the Side of a House* as the High-Mounting-Point.
* Taking what the Customer already has and building
on that; to make the installation as simple and easy
as possible. {A No Brainer}
~ RHF
.
arthr...@webtv.net
>
> - Reception was outstanding,considering the RFI
> - and other man-made noise omnipresent over here.
>
> Several years ago I bought a used Wellbrook [UK]
>
> - Show quoted text -
Palomar's currently sold 9:1 transformer is good only for a longwire,
but not for T2FD. The one made by Welbrook is the right
thing,however. I think. The RFsystems MLB is a nice one,however. Have
been using it lately indoors(!) , in conjunction with a really heavy
gauge wire of around 20 feet with fairly decent results. Have you
tried disconnecting the ground connection in the sloper? Sometimes,the
signal level goes up,mysteriously...
Just Plain Burr
"RHF"
I guess that the SWL Sloper Antenna Designs by
both Alpha Delta and Eavesdropper were built around
using the Side of a House* as the High-Mounting-Point.
* Taking what the Customer already has and building
on that; to make the installation as simple and easy
as possible. {A No Brainer}
~ RHF
.
Roy, I use three poles mounted to the fence.Then the feed drops to the eves
and a ground block (that saved me last month)then into my office/shack.
Lighting did get me from my Wi-Fi. It jumped around on my desk so fast and
was over before I could move. All radios were OK.
Burr's Radio Shack
Red Mountain, California / Bulacan, Philippines
Shortwave Receivers :
Grundig Satellit 800 Millennium
Drake SW8
Uniden BC895XLT & 245XLT
Grundig Yacht Boy 400
Antennas:
Long Wire Sloping "L"
Stoner Dymek DA100D
Discone Antenna
RHF
>
> > I already have two SWL Antennas up here in
> > Twain Harte, CA -but- neither seems bring in
> > Europe; the Middle-East; Africa and India.
>
> That's why they call it DX, I guess! Our California location simply
> is not at anybody's target area, and only occasionally off the
> backside of the beam. If we were in someone's sights, or if we had
> that extra bit of ocean between us and them, we'd probably hear them
> better.
>
- use relays to get their point across, resulting in service only from
- other locations. The ones that still use their native soils for
- transmitting to us - Czechia, Romania, Albania - all manage fairly
- well some of the time.
-
- India is especially absent from California airwaves.
- Don't know why, exactly.
-
- Bruce Jensen
Yeah the 'relays' are out-there :
15540 kHz @ 22:15 UTC RNW in Dutch -via- Bonaire, NA
with Good Audio & S-Meter : S7 & SIO 454
OTA @ 22:27 UTC with background noise S3
17820 kHz @ 22:40 UTC DW in German -via- SC, USA
with Very Good Audio & S-Meter : S0~S3 & SIO 555
WHRI ID @ 23:00 UTC followed by DW ID in German
Booming-in from the South :
17680 kHz @ 22:45 UTC CVC in Spanish from Chile
with BOOMING Audio -but- S-Meter : S0~S3 & SIO 555
~ RHF
.
RHF
BURR,
Stay Safe In and Out of Your Radio Shack.
remember - none of us are as
'quick' as lightning ;;-}} ~ RHF
.
.
RHF
> RHF wrote:
>
> > Given an area where you could locate a Sloper Antenna
> > with a Tall Mounting Pole "Top-End-Feed-Point' and the
> > ability to move the Bottom-Far-End around the full circle
> > of 360 Degrees.
>
> > best DXing ? [ N ? E ? W ? S ? ]& WHY ?
>
- omnidirectional.
OK but most are 'in' close-in space with all sorts
of things around them.
- Most of the radiation happens at the feed point.
Yes there is more power radiating around the feed-point.
-but- I a talking about a SWL Receiving Antenna.
- The slantwire and the support structure form a
- low Q mass that also radiates, equally well in
- all directions.
Not 'If' the Support Structure is a Grounded Metal
Tower/Mast.
Many of the Commercial Slopers use an attached
Counterpoise Insulated Wire to hang-down to the
ground along the Side of a Building to act as the
Grounded Tower/Mast {Reflector} to give the Sloper
some directivity and to better 'Match' the Antenna
to the Feed-in-Line.
http://www.universal-radio.com/catalog/sw_ant/0013.jpg
http://www.alphadeltacom.com/images/dxswl.gif
http://t2k.wdfiles.com/local--files/shortwave-receiving-antennas/super-sloper-002.jpg
"A Sloper which is at an angle they will be more
directional the direction that they are sloped."
http://www.angelfire.com/mb/amandx/dipole.html
Full 1/2 Wave Sloper Antenna : The radiation
pattern will be almost omnidirectional ... with
a slight advantage toward the "sloping" direction.
http://www.hamradiosecrets.com/ham-radio-hf-antenna.html
Half 1/4 Wave Sloper Antenna : Omni-Directional
pattern, but with some "warping" in the direction
of the wire slope.
http://mysite.ncnetwork.net/resvzazs/80endfed.htm
1/4 Wave Sloper : It does appear to offer gain
in the direction of the sloping element.
http://home.centurytel.net/WD0M/antennas1.html
Some of this may be the fact that these Slopers
are Mounted to Metal Towers/Masts and the
Grounded Tower/Mast may be acting like a back
Reflector and causing some of the Radiated
Directivity from the Tower to the Sloping Wire
and out away from them.
.
meanwhile i will keep my antennas on ~ RHF
http://k9zw.files.wordpress.com/2007/06/parabol.gif
.
.
RHF
>
> > RHF wrote:
> > > What is the Best Direction to 'Point' a Sloper Antenna for DX ?
>
> > > Given an area where you could locate a Sloper Antenna
> > > with a Tall Mounting Pole "Top-End-Feed-Point' and the
> > > ability to move the Bottom-Far-End around the full circle
> > > of 360 Degrees.
>
> > > Where would you place 'Point' the Bottom-Far-End for the
> > > best DXing ? [ N ? E ? W ? S ? ]& WHY ?
>
> > of the radiation happens at the feed point. The slantwire and the
> > support structure form a low Q mass that also radiates, equally well in
> > all directions.
- Dale P. has always recommended using his PAR
- end-fed as a sloper with the feedpoint near the
- bottom and thus giving a nice short run to ground.
- Good omni results and a high radiation angle.
- I think this would work for me if I did not have such
- a battery of RFI generators around my home.
-
- Bruce
Someone else suggested a "V" Sloper with a near
Ground Feed-Point and two extended Arms both
Sloping-Up and Spreading-Apart. Using a Dipole
4:1 Matching Transformer. Pointing the Bottom
of the "V" like the Tip of an Arrow in the Direction
of the Target Zone : N-E-W-S ?
Sort of like 'reversing' {in-versing} the set-up of the
Alpha Delta DX-Ultra Dipole Antenna :
Center Down & Tips Up and Away
http://www.universal-radio.com/catalog/sw_ant/3377.html
The AD DX-U Dipole Antenna is 82 Feet Tip-to-Tip
-so- Each Arm would be 41 Feet Long
-but- Did not have any suggestion on the Elevation
of the Tips or the Spread between the Tips.
For SWLing a 30 Degree Angle of Elevation {versus
the HAM 45 Degrees} with a like Degree of Spread
between the Arms.
* Bottom Feed-Point at One Foot (1')
* Tips Topped at 21.5 Feet
* Tips Spread at 20.5 Feet
Ground Foot-Print under the Arms 36 Feet.
Ground Area ~380 Sq Ft = 21x36/2
~ RHF
.
.
Brian Gregory [UK]
news:9c-dnZ5uOutd2eLR...@iwvisp.com...
> Lighting did get me from my Wi-Fi. It jumped around on my desk so fast and
> was over before I could move. All radios were OK.
Lightening not lighting I presume.
From your Wi-Fi?
In what sense from your Wi-Fi?
--
Brian Gregory. (In the UK)
n...@bgdsv.co.uk
To email me remove the letter vee.
Brian Gregory [UK]
news:5de73a0c-2e8f-48a4...@k10g2000yqa.googlegroups.com...
> Palomar's currently sold 9:1 transformer is good only for a longwire,
> but not for T2FD.
How can that be?
arthr...@webtv.net
> <arthrny...@webtv.net> wrote in message
Because the presently made MLB-1 by Palomar Engineersis a UNUN for a
longwire. The older transformer which I used (may have the original
instruction paper somewhere) was a true BALUN. To build a T2FD we must
use a balun, since it is a broadband dipole.
RHF
> On Sep 2, 5:21 pm, "Brian Gregory [UK]" <n...@bgdsv.co.uk> wrote:
>
> > <arthrny...@webtv.net> wrote in message
>
> >news:5de73a0c-2e8f-48a4...@k10g2000yqa.googlegroups.com...
- - - Palomar's currently sold 9:1 transformer
- - - is good only for a longwire, but not for T2FD.
- - How can that be?
> > --
>
> > Brian Gregory. (In the UK)
> > n...@bgdsv.co.uk
> > To email me remove the letter vee.
- Because the presently made MLB-1 by Palomar Engineersis a UNUN for
a
- longwire. The older transformer which I used (may have the original
- instruction paper somewhere) was a true BALUN. To build a T2FD we
must
- use a balun, since it is a broadband dipole.
Buy the PAR Balun which has a Floating Ground
Termainal which makes it an BAL-UN or you can
connect the Floating Ground to the Coax Ground
and have a UN-UN.
http://www.monitoringtimes.com/html/mt2003reviews.html#PAR%20End%20Fed%20Z%20EF-SWL%20Antenna
Opps to Buy the PAR Balun you have to buy
the PAR EF-SWL Antenna which includes the
http://www.grove-ent.com/ANT8.html
http://www.parelectronics.com/pdf/EF-SWL.pdf
http://www.universal-radio.com/catalog/sw_ant/2205.html
Balun and 45 Feet of HQ* Antenna Wire.
"Flex Weave" covered by a protective black
polyethylene jacket.
* 45 Feet of AWG #14 Black Polyethylene Coated
"Flex-Weave" Antenna Wire which is made up of
168 Strands of #36 Gauge Woven Copper Wires.
{This is Great Stuff}
http://www.radiobanter.com/showthread.php?t=124225
Yes with the PAR EF SWL Antenna you can Rig-It
Your Way ! - iane ~ RHF
.
dave
> On Sep 2, 10:41 pm, arthrny...@webtv.net wrote:
>> On Sep 2, 5:21 pm, "Brian Gregory [UK]"<n...@bgdsv.co.uk> wrote:
>>
>>> <arthrny...@webtv.net> wrote in message
>>
>>> news:5de73a0c-2e8f-48a4...@k10g2000yqa.googlegroups.com...
>
> - - - Palomar's currently sold 9:1 transformer
> - - - is good only for a longwire, but not for T2FD.
>
> - - How can that be?
>
> Your Way ! - iane ~ RHF
> .
You can use 450 Ohm ladder line to feed your T2FD
Brian Gregory [UK]
news:53e82383-e1ab-4705...@s9g2000yqd.googlegroups.com...
> Because the presently made MLB-1 by Palomar Engineersis a UNUN for a
> longwire. The older transformer which I used (may have the original
> instruction paper somewhere) was a true BALUN. To build a T2FD we must
> use a balun, since it is a broadband dipole.
A long wire balun should not assume you want a common ground connection on
the input and output.
But I've look at the picture and description of the MLB-1 on the web and I
agree it's far from clear what connections are provided.
However if I bought it and found it did have the grounds joined I'd return
it as unacceptable because when using a long wire you want to use a separate
good quality earth which is not joined to your receiver's earth which may
have RF noise on it.
dave
I disagree. Use on an UnUn (autotransformer) puts all points of the
system at ground, provided you ground per electrical code. "Noise" from
the radio chassis (?) flows to ground through the IEC cable. Static
charges from the antenna system flow to ground at the transmission line
point of entry.
arthr...@webtv.net
Very true,but the interference won't allow appropriate low-noise
reception at my location. I have to use coax.
arthr...@webtv.net
> <arthrny...@webtv.net> wrote in message
MLB-1 from Palomar is probably (I would rate that at 99%) their answer
to the MLB from RF Systems in the Netherlands. I still have the
latter and it has only one connection for the antenna on the top. P.S.
Just checked back Palomar's website and a true 9:1 balun kit is still
available,but it is made for transmitting up to 250W,not for SWL and
does not have any enclosure box. And it is certainly much bigger and
heavier than the old one I originally used for T2FD.
dave
Common mode rejection of noise happens in a truly balanced configuration.
dave
>>
>> Brian Gregory. (In the UK)
>> n...@bgdsv.co.uk
>> To email me remove the letter vee.
>
> MLB-1 from Palomar is probably (I would rate that at 99%) their answer
> to the MLB from RF Systems in the Netherlands. I still have the
> latter and it has only one connection for the antenna on the top. P.S.
> Just checked back Palomar's website and a true 9:1 balun kit is still
> available,but it is made for transmitting up to 250W,not for SWL and
> does not have any enclosure box. And it is certainly much bigger and
> heavier than the old one I originally used for T2FD.
I'm pretty sure the Palomar's been out longer. I've had one for 14
years, drove to Escondido and bought it at the factory.
http://www.qrp.pops.net/images/before 2008/UNUN-1.JPG
arthr...@webtv.net
> Brian Gregory [UK] wrote:
> > <arthrny...@webtv.net> wrote in message
>
> - Show quoted text -
My own cell-phone generates more noise than some of the cold war era
jammers,sometimes! That is another reason for using coax. And
grounding may bring more problems,sometimes it is better not to
ground. Static usually is not a major issue over here at my lattitude
(40* N).
John Smith
> ...
> Common mode rejection of noise happens in a truly balanced configuration.
That is the worst suggestive BS I have ever seen, no antenna knows the
difference between "RF noise" and a desirable RF signal ...
Regards,
JS
arthr...@webtv.net
...I believe that is true for transmission lines,etc. On the other
hand, an antenna (especially broadband) will pick up any
electromagnetic wave/disturbance,whether it is RF,spark and so on ad
infinitum... Including lightning. Unfortunately.
Brian Gregory [UK]
news:4c818fac$0$5504$bd46...@news.dslextreme.com...
All I ccan suggest is that you try it.
If I comapre reception on the lower bands between using my own earth made
from a copper pipe hammered into the ground somewhat away from the house to
that using the mains earth I find there is way more noise using the mains
earth and using both earths is almost as bad.
dave
>> - Show quoted text -
>
> My own cell-phone generates more noise than some of the cold war era
> jammers,sometimes! That is another reason for using coax. And
> grounding may bring more problems,sometimes it is better not to
> ground. Static usually is not a major issue over here at my lattitude
> (40* N).
GMS phones seem to get into everything. I'd look for an audio path, not
via HF radio circuitry.
Snow blowing across a wire antenna generates static electricity.
Grounding the transmission line where it enters a structure is
consistent with good operating practice. My radio floats on a 13 VDC
switch mode power supply. The only ground is the coaxial cable from the
feedthru.
dave
The noise is in-phase and cancels when the transmission line is
terminated in a "differential" input. The desired signal is + on one leg
and - on the other. The desired signal remains after differential summation.
John, lo:
http://en.wikipedia.org/wiki/Balanced
Any external signal sources tend to induce only a common mode signal on
the line and the balanced impedances to ground minimizes differential
pickup due to stray electric fields. The conductors are sometimes
twisted together to ensure that each conductor is equally exposed to any
external magnetic fields that could induce unwanted noise.
Some balanced lines also have electromagnetic shielding to reduce the
amount of noise introduced.
A balanced line allows a differential receiver to reduce the noise on a
connection by rejecting common-mode interference. The lines have the
same impedance to ground, so the interfering fields or currents induce
the same voltage in both wires. Since the receiver responds only to the
difference between the wires, it is not influenced by the induced noise
voltage. If twisted pair becomes unbalanced, for example due to
insulation failure, noise will be induced. Examples of twisted pairs
include Cat-3 Ethernet cables or telephone wires.
Compared to unbalanced circuits, balanced lines reduce the amount of
noise per distance, allowing a longer cable run to be practical. This is
because electromagnetic interference will affect both signals the same
way. Similarities between the two signals are automatically removed at
the end of the transmission path when one signal is subtracted from the
other.
[edit]
dave
GSM?
Kevin Alfred Strom
I think what Dave was saying is that open wire feeders will not pick
up noise (or signals, for that matter) if they are truly balanced,
because of common mode rejection. Which is true.
With all good wishes,
Kevin, WB4AIO.
--
http://kevinalfredstrom.com/
RHF
Arthrny,
Take a look at the WinRadio LWA-0130
Long Wire Antenna Adapter which uses
Two (2) Ferite Toroidals {Dual Transformer}.
http://www.winradio.com/home/lwa.htm
http://www.grove-ent.com/WR0130.html
Works as well {IMHO} as the RF Systems Magnetic
Longwire Balun (MLB) at about half the price.
http://groups.google.com/group/rec.radio.shortwave/msg/ac6e768de54f9404
.
Two Magnetic Longwire Baluns (MLB)s :
Palomar MLB-1 and RF Systems MLB
http://groups.google.com/group/rec.radio.shortwave/msg/586447a7ae8b3d82
Links : Magnetic Longwire Baluns (MLBs)
http://wiki.radioreference.com/index.php/HF_Antennas
.
hope this helps - iane ~ RHF
.
.
RHF
> arthrny...@webtv.net wrote:
> > On Sep 3, 10:49 am, dave<d...@dave.dave> wrote:
> >> RHF wrote:
> >>> On Sep 2, 10:41 pm, arthrny...@webtv.net wrote:
> >>>> On Sep 2, 5:21 pm, "Brian Gregory [UK]"<n...@bgdsv.co.uk> wrote:
>
> >>>>> <arthrny...@webtv.net> wrote in message
>
> >>>>>news:5de73a0c-2e8f-48a4...@k10g2000yqa.googlegroups.com...
>
> >>> - - - Palomar's currently sold 9:1 transformer
> >>> - - - is good only for a longwire, but not for T2FD.
>
> >>> - - How can that be?
>
> >>> Your Way ! - iane ~ RHF
> >>> .
>
> >> You can use 450 Ohm ladder line to feed your T2FD
>
> > Very true,but the interference won't allow appropriate low-noise
> > reception at my location. I have to use coax.
- Common mode rejection of noise happens
- in a truly balanced configuration.
Dave ? truly balanced configuration ?
Isn't that often harder to achieve
then simply using Coax Cable ?
iwtk ~ RHF
.
Brian Gregory [UK]
Have you tried using batteries, or even a linear power supply.
You may be amazed how much noise on the lower bands just vanishes when you
do.
RHF
> On Sep 4, 12:31 am, John Smith <assemblywiz...@gmail.com> wrote:
>
> > On 9/3/2010 10:01 PM, dave wrote:
>
> > > ...
> > > Common mode rejection of noise happens in a truly balanced configuration.
>
> > That is the worst suggestive BS I have ever seen, no antenna knows the
> > difference between "RF noise" and a desirable RF signal ...
>
> > Regards,
> > JS
>
- On the other hand, an antenna (especially broadband)
- will pick up any electromagnetic wave/disturbance,
- whether it is RF,spark and so on ad infinitum...
- Including lightning. Unfortunately.
Yes Antennas are suposed to be RF/EMF Signal
Gathers {Attractors}; and they do collect everthing
in the 'ether' around them.
http://en.wikipedia.org/wiki/Antenna_%28radio%29
The for the average DIY'er installation and use
of Coax Cable is generally so much easier and
problem free then Twin-Lead or Ladder-Line.
http://en.wikipedia.org/wiki/Coaxial_cable
Plus you can find RG-6/UQ Coax Cable just about
anywhere Walmart, ACE Home Depot, Amazon,
RadioShack, etc at a relatively low cost.
http://www.amazon.com/dp/B0036G6J0A
That's Why Coax Cable is the Feed-in-Line
of 'Choice' - iane ~ RHF
http://www.bluejeanscable.com/articles/rg6.htm
.
.
RHF
> arthrny...@webtv.net wrote:
> >> - Show quoted text -
>
> > My own cell-phone generates more noise than some of the cold war era
> > jammers,sometimes! That is another reason for using coax. And
> > grounding may bring more problems,sometimes it is better not to
> > ground. Static usually is not a major issue over here at my lattitude
> > (40* N).
>
> GMS phones seem to get into everything. I'd look for an audio path, not
> via HF radio circuitry.
>
> Snow blowing across a wire antenna generates static electricity.
> Grounding the transmission line where it enters a structure is
> consistent with good operating practice.
- My radio floats on a 13 VDC switch mode power supply.
- The only ground is the coaxial cable from the feedthru.
Dave - There is "Floats" Floating
-and-
There Is "Isolated" as in NO Connection [.]
ISOLATED IS BETTER IMHO - iane ~ RHF
DPDT Knife Switch "Isolated" AC-to-DC Power
Charger and DC Source :
OFF : AC-to-DC 12 V Charger* = Charging Side {Radio Off}
-and- No Connection to the Radio
* Filtered Power Strip for Charger's : On & Off
DPDT Knife Switch Center = 12 VDC Battery#
http://www.enasco.com/prod/images/products/85/AC098376l.jpg
http://image.made-in-china.com/2f0j00qCoQrfLgIubz/Knife-Switch-Double-Throw.jpg
# SLA Battery 12 VDC @ 7.2 AH easily runs the
Grundig Satellit 800-M for 8~12 Hours {all-night}.
ON : Shortwave Radio = Radio Listening Side {Radio On}
-and- No Connection to the AC Mains
All crammed into a Wooden Shoe Box.
The Little Sony ICF-SW7800GR "World Band"
Receiver is easier with a NiMH Battery Charger
and Two Set of 4 "AA" Batteries. {2500mAh}
http://www.universal-radio.com/catalog/portable/0360.html
.
.
RHF
> John Smith wrote:
> > On 9/3/2010 10:01 PM, dave wrote:
>
> >> ...
> >> Common mode rejection of noise happens in a truly balanced configuration.
>
> > That is the worst suggestive BS I have ever seen, no antenna knows the
> > difference between "RF noise" and a desirable RF signal ...
>
> > Regards,
> > JS
>
> The noise is in-phase and cancels when the transmission line is
> terminated in a "differential" input. The desired signal is + on one leg
> and - on the other. The desired signal remains after differential summation.
>
> John, lo:
>
> http://en.wikipedia.org/wiki/Balanced
>
> Any external signal sources tend to induce only a common mode signal on
> the line and the balanced impedances to ground minimizes differential
> pickup due to stray electric fields. The conductors are sometimes
> twisted together to ensure that each conductor is equally exposed to any
> external magnetic fields that could induce unwanted noise.
>
> Some balanced lines also have electromagnetic shielding to reduce the
> amount of noise introduced.
>
on a
- connection by rejecting common-mode interference. The lines have the
- same impedance to ground, so the interfering fields or currents
induce
- the same voltage in both wires. Since the receiver responds only to
the
- difference between the wires, it is not influenced by the induced
noise
- voltage. If twisted pair becomes unbalanced, for example due to
- insulation failure, noise will be induced. Examples of twisted pairs
- include Cat-3 Ethernet cables or telephone wires.
-
- Compared to unbalanced circuits, balanced lines reduce the amount of
- noise per distance, allowing a longer cable run to be practical.
This is
- because electromagnetic interference will affect both signals the
same
- way. Similarities between the two signals are automatically removed
at
- the end of the transmission path when one signal is subtracted from
the
- other.
Dave,
That is why an all-in-one simple Speaker Wire*
Dipole or Loop Antenna can provide such good
results for basic Shortwave Radio Listening; and
at a very low cost plus simplicity of build.
http://www.ginelectronics.com/catalog/images/steren%20speaker%20wire.jpg
* Get the Speaker Wire with one Lead Silver
colored and the other Lead Copper colored.
http://www.cnet.com/i/hlp/HT_speaker3.jpg
Makes it easy to tell one side from the other.
Note #s 16 or 18 AWG Speaker Wire are good
for Shortwave Antennas; and #24 AWG can
make a nice [Stealthy] SWL Antenna.
Run the Speaker Wire as mini Twin-Lead out
to the Point where you want the Antenna to
start and make an Overhand Knot in the Wire.
From this point split the 2-Wires apart; and run
each wire in opposite directions to form a Dipole
-or- run each Wire around to form a Loop and
connect the two Bare Wire Ends to made the
Loop Connection complete.
Some people use an Antenna Insulator where
the Knot is formed to use for Mounting/Rigging.
http://hf-antenna.com/009/s_insulators.jpg
While others use a Single Ferrite Bead with
2~4 Turns of the twin Pair of Wires before the
Splitting of the Pair.
http://www.dansdata.com/images/io022/beads560.jpg
http://www.newark.com/productimages/nio/standard/4652265.jpg
Naturally the Speaker Wire functions as a
Balanced Feed-in-Line {Pair of Twin Leads}
from the Knot to the Radio.
keeping it simple and practical - iane ~ RHF
.
.